treatments-xml/data/7E/52/EA/7E52EA6DC7075FAF8A32E4CFDCD7000D.xml

<document ID-DOI="http://dx.doi.org/10.3897/zookeys.1079.76412" ID-GBIF-Dataset="90785384-12f1-40ef-aa18-5e08ff36e4bc" ID-PMC="PMC8741714" ID-Pensoft-Pub="1313-2970-1079-145" ID-Pensoft-UUID="C75BE4A1E65C51598D01C9EA871B90E5" ID-PubMed="35068961" ID-ZooBank="55F9DF83DE924EC3ACEC05AA4466F147" ModsDocID="1313-2970-1079-145" checkinTime="1641053224064" checkinUser="pensoft" docAuthor="Wittmann, Karl J. &amp; Chevaldonne, Pierre" docDate="2021" docId="7E52EA6DC7075FAF8A32E4CFDCD7000D" docLanguage="en" docName="ZooKeys 1079: 145-227" docOrigin="ZooKeys 1079" docPubDate="2021-12-31" docSource="http://dx.doi.org/10.3897/zookeys.1079.76412" docTitle="Mysidetes hanseni Zimmer 1914" docType="treatment" docVersion="5" id="C75BE4A1E65C51598D01C9EA871B90E5" lastPageNumber="145" masterDocId="C75BE4A1E65C51598D01C9EA871B90E5" masterDocTitle="First report of the order Mysida (Crustacea) in Antarctic marine ice caves, with description of a new species of Pseudomma and investigations on the taxonomy, morphology and life habits of Mysidetes species" masterLastPageNumber="227" masterPageNumber="145" pageNumber="145" updateTime="1668151265394" updateUser="ExternalLinkService">
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<mods:title>First report of the order Mysida (Crustacea) in Antarctic marine ice caves, with description of a new species of Pseudomma and investigations on the taxonomy, morphology and life habits of Mysidetes species</mods:title>
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<mods:name type="personal">
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<mods:roleTerm>Author</mods:roleTerm>
</mods:role>
<mods:namePart>Wittmann, Karl J.</mods:namePart>
<mods:affiliation>Department of Environmental Health, Medical University of Vienna, Kinderspitalgasse 15, 1090 Vienna, Austria. Corresponding author</mods:affiliation>
<mods:nameIdentifier type="email">karl.wittmann@meduniwien.ac.at</mods:nameIdentifier>
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<mods:name type="personal">
<mods:role>
<mods:roleTerm>Author</mods:roleTerm>
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<mods:namePart>Chevaldonne, Pierre</mods:namePart>
<mods:affiliation>IMBE, CNRS, IRD, Aix Marseille Universite, Avignon Universite, Station Marine d'Endoume, Rue de la Batterie des Lions, 13007 Marseille, France</mods:affiliation>
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<mods:date>2021</mods:date>
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<mods:number>2021-12-31</mods:number>
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<mods:number>1079</mods:number>
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<mods:start>145</mods:start>
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<mods:url>http://dx.doi.org/10.3897/zookeys.1079.76412</mods:url>
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<mods:identifier type="DOI">http://dx.doi.org/10.3897/zookeys.1079.76412</mods:identifier>
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<subSection pageId="0" pageNumber="145" type="habitat">
<treatment ID-GBIF-Taxon="191828698" LSID="urn:lsid:plazi:treatment:7E52EA6DC7075FAF8A32E4CFDCD7000D" httpUri="http://treatment.plazi.org/id/7E52EA6DC7075FAF8A32E4CFDCD7000D" lastPageNumber="145" pageId="0" pageNumber="145">
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<taxonomicName LSID="7E52EA6D-C707-5FAF-8A32-E4CFDCD7000D" authority="Zimmer, 1914" authorityName="Zimmer" authorityYear="1914" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes hanseni" order="Mysida" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="hanseni">Mysidetes hanseni Zimmer, 1914</taxonomicName>
</paragraph>
</subSubSection>
<subSubSection pageId="0" pageNumber="145" type="description">
<paragraph pageId="0" pageNumber="145">
<figureCitation captionStart="Figure 14" captionStartId="F14" captionText="Figure 14. Mysidetes hanseni in its natural habitat inside ice cave of Damiers Islands, Antarctica A adult male, dorsal B incubating female, dorsal C physical aspect of habitat." figureDoi="10.3897/zookeys.1079.76412.figure14" httpUri="https://binary.pensoft.net/fig/629324" pageId="0" pageNumber="145">Figures 14</figureCitation>
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">, 15</figureCitation>
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">, 16</figureCitation>
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">, 17</figureCitation>
<figureCitation captionStart="Figure 18" captionStartId="F18" captionText="Figure 18. Cardiac portion of foregut in Mysidetes hanseni from ice cave of Curie Islands, Antarctica; pyloric parts removed. Adult female BL 23.4 mm. A foregut in slightly oblique lateral view, lower-case labels indicate dorsolateral infoldings (di), lateralia (la), mid-gut (mg), esophagus (oe), pigment bodies (pb), and storage space (sp) B spine from dorsolateral infoldings C spinose lobe of posterior part of lateralia D, E spines from anterior parts of lateralia." figureDoi="10.3897/zookeys.1079.76412.figure18" httpUri="https://binary.pensoft.net/fig/629328" pageId="0" pageNumber="145">, 18</figureCitation>
<figureCitation captionStart="Figure 19" captionStartId="F19" captionText="Figure 19. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm. A thoracopod 8, rostral B penis C-E series of male pleopods 1, 3, 5, caudal (C, D) and rostral (E) face, many setae broken F uropods, dorsal, setae omitted G telson." figureDoi="10.3897/zookeys.1079.76412.figure19" httpUri="https://binary.pensoft.net/fig/629329" pageId="0" pageNumber="145">, 19</figureCitation>
<figureCitation captionStart="Figure 20" captionStartId="F20" captionText="Figure 20. Nauplioid larva of Mysidetes hanseni from ice cave of Damiers Islands, Antarctica A larva at late substage N 2, lateral B antennae and mouth field, ventral, lower-case labels indicate antennula (a 1), antenna (a 2), labrum (l) and mandibles (m) with palp (p) C tip of antennula D tip of abdomen with caudal furca, lateral. A, larva artificially separated from background; A-D are from four different specimens." figureDoi="10.3897/zookeys.1079.76412.figure20" httpUri="https://binary.pensoft.net/fig/629330" pageId="0" pageNumber="145">, 20</figureCitation>
<figureCitation captionStart="Figure 25" captionStartId="F25" captionText="Figure 25. Surface details of appendix masculina and its female homologue in series of increasing body size for Mysidetes illigi (A-C) and M. hanseni (D) from Antarctic ice caves. A immature male BL 12.1 mm B subadult male 14.7 mm C adult female 18.4 mm D adult male 24.7 mm." figureDoi="10.3897/zookeys.1079.76412.figure25" httpUri="https://binary.pensoft.net/fig/629335" pageId="0" pageNumber="145">, 25D</figureCitation>
</paragraph>
</subSubSection>
<subSubSection pageId="0" pageNumber="145" type="reference_group">
<paragraph pageId="0" pageNumber="145">
<taxonomicName authorityName="Zimmer" authorityYear="1914" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes hanseni" order="Mysida" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="hanseni">Mysidetes hanseni</taxonomicName>
Zimmer, 1914: 403, 404, Figs 43-46 in Fig.-Tab. XXV (first description); 
<bibRefCitation DOI="https://doi.org/10.1017/S0954102098000029" author="Brandt, A" journalOrPublisher="Antarctic Science" pageId="0" pageNumber="145" pagination="3 - 11" refId="B10" refString="Brandt, A, Muehlenhardt-Siegel, U, Siegel, V, 1998. An account of the Mysidacea (Crustacea, Malacostraca) of the Southern Ocean. Antarctic Science 10: 3 - 11, DOI: https://doi.org/10.1017/S0954102098000029" title="An account of the Mysidacea (Crustacea, Malacostraca) of the Southern Ocean." url="https://doi.org/10.1017/S0954102098000029" volume="10" year="1998">Brandt et al. 1998</bibRefCitation>
: Tab. 
<tableCitation captionStart="Table 1" captionStartId="T1" captionText="Table 1. Sensory structures in Mysidae from ice caves and other marine habitats." httpUri="http://table.plazi.org/id/E5F3A01152EDB7E94BBEF0E7B7DCA5C6" pageId="0" pageNumber="145" tableUuid="E5F3A01152EDB7E94BBEF0E7B7DCA5C6">1</tableCitation>
(endemism); 
<bibRefCitation author="Price, WW" journalOrPublisher="Northwest Atlantic Fisheries Organization, Serial No. N 1693" pageId="0" pageNumber="145" publicationUrl="http://www.marinespecies.org/aphia.php?p=sourcedetails&amp;id=4191" refId="B72" refString="Price, WW, 2001. Mysinae. In: World list of Mysidacea. NeMys doc_id: 3677. http://www.marinespecies.org/aphia.php?p=sourcedetails&amp;id=4191" title="Mysinae. In: World list of Mysidacea. NeMys doc _ id: 3677." url="http://www.marinespecies.org/aphia.php?p=sourcedetails&amp;id=4191" year="2001">Price 2001</bibRefCitation>
: 111 (in list, distribution); 
<bibRefCitation author="San Vicente, C" editor="Mulder, TJ" journalOrPublisher="Nova Science Publishers, Chapter 1" pageId="0" pageNumber="145" pagination="1 - 80" refId="B76" refString="San Vicente, C, 2011a. Species Diversity of Antarctic Mysids (Crustacea: Lophogastrida and Mysida). In: Mulder, TJ, Ed., Antarctica: Global, Environmental and Economic Issues. Nova Science Publishers, Chapter 1: 1 - 80" title="Species Diversity of Antarctic Mysids (Crustacea: Lophogastrida and Mysida)." volumeTitle="Antarctica: Global, Environmental and Economic Issues." year="2011 a">San Vicente 2011a</bibRefCitation>
: 53, Tab. 4, Figs 38N, O (diagnosis, in key); 
<bibRefCitation author="Petryashov, VV" journalOrPublisher="Russian Journal of Marine Biology" pageId="0" pageNumber="145" publicationUrl="http://share.biodiversity.aq/Atlas/PDFS/Atlas_Chap.5.16-Petryashov_2014-F.pdf" refId="B68" refString="Petryashov, VV, 2014. 5.16. Lophogastrida and Mysida (Crustacea: Malacostraca: Peracarida) of the Southern Ocean. In: De Broyer C, Koubbi P, Griffiths HJ, Raymond B, d'Udekem d'Acoz C et al. (Eds) Biogeographic Atlas of the Southern Ocean (CoML/CAML Atlas). Census of Antarctic Marine Life. SCAR-Marine Biodiversity Information Network. Scientific Commitee on Antarctic Research, Cambridge, 149-154. http://share.biodiversity.aq/Atlas/PDFS/Atlas_Chap.5.16-Petryashov_2014-F.pdf" title="5.16. Lophogastrida and Mysida (Crustacea: Malacostraca: Peracarida) of the Southern Ocean. In: De Broyer C, Koubbi P, Griffiths HJ, Raymond B, d'Udekem d'Acoz C et al. (Eds) Biogeographic Atlas of the Southern Ocean (CoML / CAML Atlas). Census of Antarctic Marine Life. SCAR-Marine Biodiversity Information Network. Scientific Commitee on Antarctic Research, Cambridge, 149 - 154." url="http://share.biodiversity.aq/Atlas/PDFS/Atlas_Chap.5.16-Petryashov_2014-F.pdf" year="2014">Petryashov 2014</bibRefCitation>
: map 11 (biogeography); 
<bibRefCitation author="Mees, J" journalOrPublisher="Academic Press, London" pageId="0" pageNumber="145" publicationUrl="http://www.marinespecies.org/index.php" refId="B51" refString="Mees, J, Meland, K, 2021. World List of Lophogastrida, Stygiomysida and Mysida. World Register of Marine Species. http://www.marinespecies.org/index.php" title="World List of Lophogastrida, Stygiomysida and Mysida. World Register of Marine Species." url="http://www.marinespecies.org/index.php" year="2021">Mees and Meland 2021</bibRefCitation>
: AphiaID = 226498 (accepted).
</paragraph>
</subSubSection>
<subSubSection pageId="0" pageNumber="145" type="type series">
<paragraph pageId="0" pageNumber="145">Type series.</paragraph>
<paragraph pageId="0" pageNumber="145">
Jar (ZMB 18283) labelled &quot; 
<taxonomicName authorityName="Zimmer" authorityYear="1914" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes hanseni" order="Mysidacea" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="hanseni">
<emphasis italics="true" pageId="0" pageNumber="145">Mysidetes hanseni</emphasis>
</taxonomicName>
Zimmer. Typus. 
<normalizedToken originalValue="Gauß-Station">Gauss-Station</normalizedToken>
, leg. D.S.P. Exp.&quot; contains two vials each with one specimen preserved in ethanol. All types sampled (S#9-10) at 
<emphasis bold="true" pageId="0" pageNumber="145">Gauss Station</emphasis>
, 
<geoCoordinate degrees="66" direction="south" minutes="02" orientation="latitude" precision="925" value="-66.03333">66°02'S</geoCoordinate>
, 
<geoCoordinate degrees="89" direction="east" minutes="38" orientation="longitude" precision="925" value="89.63333">89°38'E</geoCoordinate>
, coast of East Antarctica. For prerequisites of lectotype designation, see Discussion.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Lectotype</emphasis>
by present designation (Fig. 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15</figureCitation>
). Adult male BL 18.6 mm (ZMB 18283a), vial inside labelled as &quot;D. 
<normalizedToken originalValue="Südpol">Suedpol</normalizedToken>
.-Exp. 21.12.02 vertikal 200 m. 
<taxonomicName authorityName="Zimmer" authorityYear="1914" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes hanseni" order="Mysidacea" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="hanseni">Mysidetes hanseni</taxonomicName>
Typ&quot;; S#9.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">
<emphasis italics="true" pageId="0" pageNumber="145">Paralectotype</emphasis>
.
</emphasis>
Immature male BL 8.7 mm (ZMB 18283b), vial inside labelled &quot;D. 
<normalizedToken originalValue="Südpol">Suedpol</normalizedToken>
.-Exp. 22.12.02 vert. 250 m. 
<taxonomicName authorityName="Zimmer" authorityYear="1914" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes hanseni" order="Mysidacea" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="hanseni">Mysidetes hanseni</taxonomicName>
&quot;; S#10.
</paragraph>
<paragraph pageId="0" pageNumber="145">
An additional [transl.] &quot;younger male specimen&quot; reported by 
<bibRefCitation author="Zimmer, C" editor="Drygalski, E von" journalOrPublisher="Georg Reimer, Berlin" pageId="0" pageNumber="145" pagination="377 - 445" refId="B123" refString="Zimmer, C, 1914. Die Schizopoden der deutschen Suedpolar-Expedition 1901-1903. In: Drygalski, E von, Ed., Deutsche Suedpolar-Expedition 1901-1903, XV. Zoologie. Georg Reimer, Berlin 7: 377 - 445" title="Die Schizopoden der deutschen Suedpolar-Expedition 1901 - 1903." volume="7" volumeTitle="Deutsche Suedpolar-Expedition 1901 - 1903, XV. Zoologie." year="1914">Zimmer (1914)</bibRefCitation>
is not in the ZMB collection.
</paragraph>
</subSubSection>
<subSubSection pageId="0" pageNumber="145" type="type material">
<paragraph pageId="0" pageNumber="145">Non-type material from ice caves.</paragraph>
<paragraph pageId="0" pageNumber="145">
Total of four samples (S#5-8) taken by P. 
<normalizedToken originalValue="Chevaldonné">Chevaldonne</normalizedToken>
and S. Hourdez upon diving in austral summer 2017-2018 in ice caves at the coasts of Curie and Damiers Islands, near Dumont 
<normalizedToken originalValue="d’Urville">d'Urville</normalizedToken>
Station, 
<normalizedToken originalValue="Adélie">Adelie</normalizedToken>
Land, Antarctica:
</paragraph>
<paragraph pageId="0" pageNumber="145">
Six incubating females (♀♀B-) BL 19.3-22.8 mm, 1 ♀0- 19.3 mm, 2 ♂♂A 20.5-22.2 mm, 3 ♂♂S 13.3-17.8 mm, 12 ♂♂I 7.5-12.0 mm (in vials, NHMW 27302, SMF-57649, ZMB 34484, ZMH-K-60868) and 1 ♀B- 23.4 mm (on slides, NHMW 27303), 
<emphasis bold="true" pageId="0" pageNumber="145">Curie Islands</emphasis>
, S#5; 5 ♀♀B- 22.0-22.5 mm, 1 ♀S- 20.5 mm, 1 ♂S 18.9 mm (in vials, SMF-57650, ZMH-K-60869) and 1 ♂A 24.7 mm (on slides, NHMW 27304), S#7; 13 ♀♀B- 13.5-24.2 mm, 2 ♀♀0- 16.6-17.8 mm, 5 ♂♂A 17.3-18.1 mm, 2 ♀♀S+ 18.8-21.3 mm, 1 ♀S- 19.3 mm, 4 ♂♂S 10.9-13.1 mm, 3 ♂♂I 11.5-12.1 mm, 2 juv. 7.7-7.9 mm (in vials, NHMW 27305, SMF-57651, ZMB 34485, ZMH-K-60870), S#6; 17 ♀♀B- 10.5-22.1 mm, 6 ♀♀0- 17.8-25.7 mm, 3 ♀♀S+ 17.2-21.1 mm, 6 ♂♂S 12.3-14.2 mm, 10 ♂♂I 9.2-13.4 mm, 1 ♀I 7.9 mm (in vials, NHMW 27306, SMF-57652, ZMB 34495, ZMH-K-60871), 
<emphasis bold="true" pageId="0" pageNumber="145">Damiers Islands</emphasis>
, S#8.
</paragraph>
</subSubSection>
<subSubSection pageId="0" pageNumber="145" type="diagnosis">
<paragraph pageId="0" pageNumber="145">Diagnosis.</paragraph>
<paragraph pageId="0" pageNumber="145">
Diagnosis covers adults of both sexes. Eyes (Figs 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15C</figureCitation>
, 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16A, B</figureCitation>
) well-developed, clearly longer than wide. Cornea roughly calotte-shaped with or without indentation of proximal margin, its length 0.5-0.7 times length of conical eyestalk, diameter 1.0-1.4 times length of terminal segment of antennular trunk. Cornea occupies distal third to half of eye surface. Eyestalk without papilla; length 0.9-1.2 times its maximum width at conjunction with cornea. Rostrum (Figs 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15C</figureCitation>
, 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16B</figureCitation>
, 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17D</figureCitation>
) subtriangular, terminally well-rounded; lateral margins concave (Fig. 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17D</figureCitation>
) to almost straight (Fig. 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15C</figureCitation>
), margins slightly tilted up; 0.3-0.8 times length of terminal segment of antennular trunk (measured along dorsal median line). Antero-lateral edges of carapace well-rounded (Figs 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15C</figureCitation>
, 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17D</figureCitation>
).
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Antennae</emphasis>
s.l. (Figs 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15D</figureCitation>
, 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16C</figureCitation>
, 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17A-C</figureCitation>
). Appendix masculina (Figs 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16C</figureCitation>
, 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17A</figureCitation>
) strongly setose, measured without setae 0.5-0.8 times as long as terminal segment of antennular trunk, shortly extending beyond anterior margin of this segment. Antennal sympod (Figs 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16A</figureCitation>
, 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17C</figureCitation>
) with one large, acute tooth on disto-lateral edge and, more caudally, an additional shorter tooth. Dorsal face of sympod with lappet-like to triangular lobe, in every case apically rounded. Antennal scale (Fig. 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17C</figureCitation>
) setose all around, apically rounded, two-segmented with apical segment only 2-4% total scale length; scale 4-5 times as long as its maximum width; scale projecting 0.3-0.5 times its length beyond antennular trunk (0.2-0.4 in subadults) and 0.4-0.6 times beyond antennal peduncle.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Thorax</emphasis>
(Figs 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15</figureCitation>
, 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16C</figureCitation>
, 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17G-K</figureCitation>
, 
<figureCitation captionStart="Figure 19" captionStartId="F19" captionText="Figure 19. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm. A thoracopod 8, rostral B penis C-E series of male pleopods 1, 3, 5, caudal (C, D) and rostral (E) face, many setae broken F uropods, dorsal, setae omitted G telson." figureDoi="10.3897/zookeys.1079.76412.figure19" httpUri="https://binary.pensoft.net/fig/629329" pageId="0" pageNumber="145">19A, B</figureCitation>
). Right mandible with digitus mobilis and pars centralis modified as in Fig. 
<figureCitation captionStart="Figure 11" captionStartId="F11" captionText="Figure 11. Mysidetes illigi from ice cave of Bernard Island, Antarctica. Adult females BL 18.4 mm (A, C, E), 18.1 mm (B, D) A labrum, ventral aspect B mandibles with right palp, rostral C labium D maxillula, caudal E maxilla, caudal." figureDoi="10.3897/zookeys.1079.76412.figure11" httpUri="https://binary.pensoft.net/fig/629321" pageId="0" pageNumber="145">11B</figureCitation>
; remaining mouthparts normal; labrum not produced rostrally; maxilla without spines. Thorax without mid-sternal processes in both sexes. Flagella of thoracic exopods 1 and 8 with eight segments (Fig. 
<figureCitation captionStart="Figure 19" captionStartId="F19" captionText="Figure 19. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm. A thoracopod 8, rostral B penis C-E series of male pleopods 1, 3, 5, caudal (C, D) and rostral (E) face, many setae broken F uropods, dorsal, setae omitted G telson." figureDoi="10.3897/zookeys.1079.76412.figure19" httpUri="https://binary.pensoft.net/fig/629329" pageId="0" pageNumber="145">19A</figureCitation>
), flagella 2-7 with nine segments. Carpopropodites of thoracic endopods 1-8 with 2, 2, 7-8, 7-8, 9-11, 9-10, 9 and 8-9 segments, respectively. Claw of endopod 1 strong, subapically bilaterally serrated; claws 3-8 (Fig. 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17H-K</figureCitation>
) weak, slender, smooth. Female thoracopods 7 and 8 with large oostegites, thoracopod 6 with rudimentary oostegite. Penes (Fig. 
<figureCitation captionStart="Figure 19" captionStartId="F19" captionText="Figure 19. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm. A thoracopod 8, rostral B penis C-E series of male pleopods 1, 3, 5, caudal (C, D) and rostral (E) face, many setae broken F uropods, dorsal, setae omitted G telson." figureDoi="10.3897/zookeys.1079.76412.figure19" httpUri="https://binary.pensoft.net/fig/629329" pageId="0" pageNumber="145">19B</figureCitation>
) tube-like, stiff, slender, smooth all along, without setae. Size variable in adult males: length 1.5-2.5 times length of ischium 8 and 2-3 times merus 8; penes anteriorly extending to thoracic sternites 2-5.
</paragraph>
<caption doi="10.3897/zookeys.1079.76412.figure14" httpUri="https://binary.pensoft.net/fig/629324" pageId="0" pageNumber="145" start="Figure 14" startId="F14">
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">Figure 14.</emphasis>
<taxonomicName authorityName="Zimmer" authorityYear="1914" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes hanseni" order="Mysidacea" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="hanseni">
<emphasis italics="true" pageId="0" pageNumber="145">Mysidetes hanseni</emphasis>
</taxonomicName>
in its natural habitat inside ice cave of Damiers Islands, Antarctica 
<emphasis bold="true" pageId="0" pageNumber="145">A</emphasis>
adult male, dorsal 
<emphasis bold="true" pageId="0" pageNumber="145">B</emphasis>
incubating female, dorsal 
<emphasis bold="true" pageId="0" pageNumber="145">C</emphasis>
physical aspect of habitat.
</paragraph>
</caption>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Pleopods</emphasis>
(Fig. 
<figureCitation captionStart="Figure 19" captionStartId="F19" captionText="Figure 19. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm. A thoracopod 8, rostral B penis C-E series of male pleopods 1, 3, 5, caudal (C, D) and rostral (E) face, many setae broken F uropods, dorsal, setae omitted G telson." figureDoi="10.3897/zookeys.1079.76412.figure19" httpUri="https://binary.pensoft.net/fig/629329" pageId="0" pageNumber="145">19C-E</figureCitation>
) reduced to undivided, bifid, setose plates with comparatively long endopodal portion (pseudobranchial lobe) in both sexes. All pleopods without spines, no modified setae. Uropods (Figs 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16D</figureCitation>
, 
<figureCitation captionStart="Figure 19" captionStartId="F19" captionText="Figure 19. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm. A thoracopod 8, rostral B penis C-E series of male pleopods 1, 3, 5, caudal (C, D) and rostral (E) face, many setae broken F uropods, dorsal, setae omitted G telson." figureDoi="10.3897/zookeys.1079.76412.figure19" httpUri="https://binary.pensoft.net/fig/629329" pageId="0" pageNumber="145">19F</figureCitation>
) entire, slender, setose all around, no spines; exopod extends by 18-29% its length beyond endopod.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Telson</emphasis>
(Figs 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15B</figureCitation>
, 
<figureCitation captionStart="Figure 19" captionStartId="F19" captionText="Figure 19. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm. A thoracopod 8, rostral B penis C-E series of male pleopods 1, 3, 5, caudal (C, D) and rostral (E) face, many setae broken F uropods, dorsal, setae omitted G telson." figureDoi="10.3897/zookeys.1079.76412.figure19" httpUri="https://binary.pensoft.net/fig/629329" pageId="0" pageNumber="145">19G</figureCitation>
) trapezoid, length twice maximum width near basis and 5-6 times width shortly above bifid terminus; 0.7-0.9 times exopod of uropod. Each lateral margin armed almost all along with 45-57 small spines. Sub-basal spine-free portion, if any, up to 1/10 telson length in adults (occasionally longer in non-adults). Spines arranged in consecutive sets on distal half; each set represents series of 2-6 spines increasing in length distally. Triangular apical cleft (Fig. 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15B</figureCitation>
) penetrates 1/10 telson length, margins of cleft lined all along with 14-17 laminae. Telson cleft 1.0-1.8 times as deep as its width at apex. Disto-lateral lobes of telson rounded, each lobe terminally armed with 4-5 strong, subequal spines with 4-5% telson length.
</paragraph>
</subSubSection>
<subSubSection pageId="0" pageNumber="145" type="description">
<paragraph pageId="0" pageNumber="145">Description of types.</paragraph>
<paragraph pageId="0" pageNumber="145">
The initial objective for inspection of the types was the unclear state of development of male characteristics. 
<bibRefCitation author="Zimmer, C" editor="Drygalski, E von" journalOrPublisher="Georg Reimer, Berlin" pageId="0" pageNumber="145" pagination="377 - 445" refId="B123" refString="Zimmer, C, 1914. Die Schizopoden der deutschen Suedpolar-Expedition 1901-1903. In: Drygalski, E von, Ed., Deutsche Suedpolar-Expedition 1901-1903, XV. Zoologie. Georg Reimer, Berlin 7: 377 - 445" title="Die Schizopoden der deutschen Suedpolar-Expedition 1901 - 1903." volume="7" volumeTitle="Deutsche Suedpolar-Expedition 1901 - 1903, XV. Zoologie." year="1914">Zimmer (1914)</bibRefCitation>
indicated the largest specimen examined by him as [transl.] &quot;adult or subadult&quot;. We found a damaged appendix masculina (left arrow in Fig. 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15D</figureCitation>
) with a few setae, apex broken, on the right antennula of the lectotype, suggesting that this appendix was longer 
<emphasis italics="true" pageId="0" pageNumber="145">in vivo</emphasis>
, ergo the lectotype considered adult.
</paragraph>
<paragraph pageId="0" pageNumber="145">
Both available type specimens not dissected. Body proportions (Fig. 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15A</figureCitation>
) slender in both specimens as normal in males of 
<taxonomicName authorityName="Holt &amp; Tattersall" authorityYear="1906" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes" order="Mysidacea" pageId="0" pageNumber="145" phylum="Arthropoda" rank="genus">
<emphasis italics="true" pageId="0" pageNumber="145">Mysidetes</emphasis>
</taxonomicName>
species. Terminal segment of antennular trunk with 3-4 large plumose setae plus a number of smaller barbed setae on disto-mesial corner; additional large plumose seta inserted subterminally on mesial margin in both specimens. Rostrum of both specimens short, terminally broad, with slightly sigmoid, almost straight lateral margins (Fig. 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15C</figureCitation>
).
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Lectotype</emphasis>
(Fig. 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15</figureCitation>
). Cornea roughly calotte-shaped, dorsally with proximal indentation, length 0.5-0.6 times eyestalk, diameter equals length of terminal segment of antennular trunk. Eyestalk without papilla. Median segment of antennular trunk with its mesial face inflated (right arrow in Fig. 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15D</figureCitation>
), indicative of male adulthood. Antennal scale as in diagnosis, apical segment 4% total scale length; scale five times as long as its maximum width; scale projecting 0.3-0.4 times its length beyond antennular trunk and 0.6 times beyond antennal peduncle (Fig. 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15D</figureCitation>
). Flagella of thoracic exopods 1-6 as in diagnosis, flagella 7-8 broken. Carpopropodites of thoracic endopods 4-8 with 8, 10, 9, 9, and 9 segments, respectively. Claw of endopods 4-8 weak, slender, weakly bent and smooth. Penes reach to sternite 4. Pleopods as normal in the genus; length increases from pleopod 2 to 5; pleopod 1 slightly longer than pleopod 2. Uropods as in diagnosis; exopod extends by 1/5 its length beyond endopod (Fig. 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15A</figureCitation>
). Telson as in diagnosis, length five times width shortly above bifid terminus. Length 1.2 times sixth pleonite, 0.9 times endopod of uropod and 0.7-0.8 times exopod of uropod. Left (undamaged) lateral margin all along with total of about 54 spines. Most proximal portion of each lateral margin with seven crowded spines; sub-basal portion with six subequal spines positioned with lower density in continuous series; median to distal portions with about 41 spines densely arranged in consecutive sets of 2-6 spines increasing in length distally. Apical cleft penetrates by 9% telson length. Margins of cleft (Fig. 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15B</figureCitation>
) all along with total of 15 laminae increasing in size distally; largest lamina with 2/5 cleft length. Disto-lateral lobes as in diagnosis; terminal spines longer than subterminal spines.
</paragraph>
<caption doi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145" start="Figure 15" startId="F15">
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">Figure 15.</emphasis>
Lectotype of 
<taxonomicName authorityName="Zimmer" authorityYear="1914" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes hanseni" order="Mysidacea" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="hanseni">
<emphasis italics="true" pageId="0" pageNumber="145">Mysidetes hanseni</emphasis>
</taxonomicName>
Zimmer, 1914, adult male BL 18.6 mm 
<emphasis bold="true" pageId="0" pageNumber="145">A</emphasis>
body, lateral 
<emphasis bold="true" pageId="0" pageNumber="145">B</emphasis>
terminal fifth of telson 
<emphasis bold="true" pageId="0" pageNumber="145">C</emphasis>
anterior body region, dorsal 
<emphasis bold="true" pageId="0" pageNumber="145">D</emphasis>
anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. 
<emphasis bold="true" pageId="0" pageNumber="145">A</emphasis>
, 
<emphasis bold="true" pageId="0" pageNumber="145">B</emphasis>
, objects artificially separated from background.
</paragraph>
</caption>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">
<emphasis italics="true" pageId="0" pageNumber="145">Paralectotype</emphasis>
.
</emphasis>
Median segment of antennular trunk not inflated as normal in immatures. Penes reaching to sternite 6. Telson conforming well to that of lectotype, taking differences due to body size into account: right lateral margin with total of 35 spines, ten of which in approximately linear arrangement along basal and sub-basal portions, remaining spines more densely set along median to apical portions, arranged in groups as in lectotype. Apical cleft 10% telson length; numbers and relative size of laminae as in lectotype.
</paragraph>
</subSubSection>
<subSubSection pageId="0" pageNumber="145" type="colour">
<paragraph pageId="0" pageNumber="145">Colour.</paragraph>
<paragraph pageId="0" pageNumber="145">
Lectotype with well-pigmented dark cornea (Fig. 
<figureCitation captionStart="Figure 15" captionStartId="F15" captionText="Figure 15. Lectotype of Mysidetes hanseni Zimmer, 1914, adult male BL 18.6 mm A body, lateral B terminal fifth of telson C anterior body region, dorsal D anterior body region, obliquely ventral, left arrow points to remnant of broken appendix masculina, right arrow to mesial swelling of median segment of antennular trunk. A, B, objects artificially separated from background." figureDoi="10.3897/zookeys.1079.76412.figure15" httpUri="https://binary.pensoft.net/fig/629325" pageId="0" pageNumber="145">15</figureCitation>
) and large dark-brown patches on the body, the latter often observed as artefacts in century-old preserved material. By contrast, the paralectotype is completely bleached, cornea included. This suggests that the two specimens experienced different treatments before being placed in ethanol.
</paragraph>
<paragraph pageId="0" pageNumber="145">
For evaluation of differences between description by 
<bibRefCitation author="Zimmer, C" editor="Drygalski, E von" journalOrPublisher="Georg Reimer, Berlin" pageId="0" pageNumber="145" pagination="377 - 445" refId="B123" refString="Zimmer, C, 1914. Die Schizopoden der deutschen Suedpolar-Expedition 1901-1903. In: Drygalski, E von, Ed., Deutsche Suedpolar-Expedition 1901-1903, XV. Zoologie. Georg Reimer, Berlin 7: 377 - 445" title="Die Schizopoden der deutschen Suedpolar-Expedition 1901 - 1903." volume="7" volumeTitle="Deutsche Suedpolar-Expedition 1901 - 1903, XV. Zoologie." year="1914">Zimmer (1914)</bibRefCitation>
and type specimens, see Discussion.
</paragraph>
</subSubSection>
<subSubSection pageId="0" pageNumber="145" type="description">
<paragraph pageId="0" pageNumber="145">Description of ice cave specimens.</paragraph>
<paragraph pageId="0" pageNumber="145">
Includes re-description of males and first description of females. All features of the above diagnosis. General appearance of females moderately slender (not considering the marsupium), males even more slender. Body length of adult females 10.5-25.7 mm (n = 52), males 17.3-24.7 mm (n = 8). Rostrum comprising 1-3% body length, cephalothorax 32-39%, pleon 47-53%, telson 14-15% and carapace 26-31%. Frons with at least four horizontal bulges (Fig. 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16A</figureCitation>
; potential additional bulges not well verified).
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Carapace</emphasis>
(Fig. 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17D</figureCitation>
) with normal gross structure, without apparent sexual dimorphism. Rostrum covering basal portions of normally orientated eyestalks, reaching at most to middle of artificially straight forward-orientated eyestalks (without cornea). Antero-lateral edges of carapace well rounded, not visibly projecting 
<emphasis italics="true" pageId="0" pageNumber="145">in situ</emphasis>
, whereas weakly projecting in artificially expanded carapace. Posterior margin of carapace evenly rounded, mid-caudally well emarginated, leaving ultimate 1-1.5 thoracomeres dorsally exposed. Cervical sulcus strong, cardial sulcus indistinct. Median field of 44-59 crowded pores (Fig. 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17E</figureCitation>
) directly in front of cervical sulcus. Transverse series of 46-81 pores (Fig. 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17F</figureCitation>
) crossing carapace between, if present, cardial sulcus and posterior margin. Except for the here-stated structures, outer surface of carapace smooth in both sexes.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Eyes</emphasis>
(Fig. 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16A-C</figureCitation>
). Eyestalks and cornea dorsoventrally (very) weakly compressed (Fig. 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16C</figureCitation>
). In dorsal view, cornea appearing calotte-shaped, in lateral view, oviform with upper margin (= face) slightly flattened.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Antennulae</emphasis>
(Fig. 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17A, B</figureCitation>
). Trunk measures 7-9% body length in both sexes, extending 0.4-0.5 times its length beyond eyes, being 1.6-2.1 times longer than maximum width in adult males, 2.2-2.8 in adult females. Measured along dorsal midline, basal segment 42-47% trunk length, median 18-20% and terminal 33-38%. Lateral lobe from basal segment extending beyond median segment. Median segment with its mesial face inflated in adult males only. Terminal segment 0.6-0.9 times as long as wide. Part of terminal segment with cuticle sculptured by minute depressions in males only; due to their small size and density, these depressions drawn as reduced numbers of dots with exaggerated size in Fig. 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17A</figureCitation>
. Details of depressions available in Fig. 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16E</figureCitation>
for oostegite 2. Antennulae of females (Fig. 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17B</figureCitation>
) dorsally with smooth cuticle, not sculptured by minute depressions. Terminal segment of antennular trunk in both sexes with mid-dorsal apophysis bearing four barbed setae on its lateral half and small cilia along its disto-mesial margin; no spiniform anterior projection. Lateral antennular flagellum about as wide as mesial one when measured near basis.
</paragraph>
<caption doi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145" start="Figure 16" startId="F16">
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">Figure 16.</emphasis>
<taxonomicName authorityName="Zimmer" authorityYear="1914" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes hanseni" order="Mysidacea" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="hanseni">
<emphasis italics="true" pageId="0" pageNumber="145">Mysidetes hanseni</emphasis>
</taxonomicName>
from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (
<emphasis bold="true" pageId="0" pageNumber="145">A</emphasis>
, 
<emphasis bold="true" pageId="0" pageNumber="145">B</emphasis>
), 21.4 mm (
<emphasis bold="true" pageId="0" pageNumber="145">E</emphasis>
); adult male 24.7 mm (
<emphasis bold="true" pageId="0" pageNumber="145">C</emphasis>
, 
<emphasis bold="true" pageId="0" pageNumber="145">D</emphasis>
). 
<emphasis bold="true" pageId="0" pageNumber="145">A</emphasis>
head of female, obliquely lateral 
<emphasis bold="true" pageId="0" pageNumber="145">B</emphasis>
anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace 
<emphasis bold="true" pageId="0" pageNumber="145">C</emphasis>
anterior body region of male, lateral 
<emphasis bold="true" pageId="0" pageNumber="145">D</emphasis>
tail fan, lateral 
<emphasis bold="true" pageId="0" pageNumber="145">E</emphasis>
cuticle structures on outer surface of the large second oostegite.
</paragraph>
</caption>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">Antennae</emphasis>
(Fig. 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17C</figureCitation>
). Sympod dorsally with terminally rounded, tongue-like process; caudally with bulbous lobe containing end sac of antennal gland. Three-segmented antennal peduncle in both sexes with basal segment 22-25% peduncle length, second 36-43% and third 32-36%. Third segment 1.1-1.4 times as long as wide. Antennal scale with convex mesial margin; proximal half of lateral margin slightly sigmoid, distal half convex. Small apical segment with five plumose setae.
</paragraph>
<caption doi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145" start="Figure 17" startId="F17">
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">Figure 17.</emphasis>
<taxonomicName authorityName="Zimmer" authorityYear="1914" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes hanseni" order="Mysidacea" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="hanseni">
<emphasis italics="true" pageId="0" pageNumber="145">Mysidetes hanseni</emphasis>
</taxonomicName>
from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (
<emphasis bold="true" pageId="0" pageNumber="145">A</emphasis>
, 
<emphasis bold="true" pageId="0" pageNumber="145">C-F</emphasis>
, 
<emphasis bold="true" pageId="0" pageNumber="145">I</emphasis>
, 
<emphasis bold="true" pageId="0" pageNumber="145">J</emphasis>
), adult female 23.4 mm (
<emphasis bold="true" pageId="0" pageNumber="145">B</emphasis>
, 
<emphasis bold="true" pageId="0" pageNumber="145">G</emphasis>
, 
<emphasis bold="true" pageId="0" pageNumber="145">H</emphasis>
, 
<emphasis bold="true" pageId="0" pageNumber="145">K-M</emphasis>
) 
<emphasis bold="true" pageId="0" pageNumber="145">A</emphasis>
right male antennula, dorsal 
<emphasis bold="true" pageId="0" pageNumber="145">B</emphasis>
distal margin of left female antennular trunk, ventral, flagella omitted 
<emphasis bold="true" pageId="0" pageNumber="145">C</emphasis>
antenna with antennal gland, dorsal, setae omitted from antennal scale 
<emphasis bold="true" pageId="0" pageNumber="145">D</emphasis>
carapace expanded on slide, details show cervical (
<emphasis bold="true" pageId="0" pageNumber="145">E</emphasis>
) and cardial (
<emphasis bold="true" pageId="0" pageNumber="145">F</emphasis>
) pore groups 
<emphasis bold="true" pageId="0" pageNumber="145">G-K</emphasis>
tarsus in series of thoracic endopods 2-5, 8, setae omitted 
<emphasis bold="true" pageId="0" pageNumber="145">L</emphasis>
tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (
<emphasis bold="true" pageId="0" pageNumber="145">M</emphasis>
) shows transverse pore groups. 
<emphasis bold="true" pageId="0" pageNumber="145">E</emphasis>
, 
<emphasis bold="true" pageId="0" pageNumber="145">F</emphasis>
, 
<emphasis bold="true" pageId="0" pageNumber="145">M</emphasis>
, pore diameters not to scale.
</paragraph>
</caption>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">
<emphasis italics="true" pageId="0" pageNumber="145">Mandibles</emphasis>
.
</emphasis>
Segments 1-3 contributing 11-14%, 53-60% and 29-33% length to three-segmented palp. Proximal segment without setae. Median segment 2.7-3.3 times as long as its maximum width, both margins setose all along. Terminal segment strongly setose along mesial margin; distal 2/3 in addition with series of short setae on caudal face near lateral margin. Pars incisiva with 4-5 teeth. Left mandible normal, its digitus mobilis strong, with 3-4 teeth and its pars centralis with 3-4 separate, spiny teeth. Right mandible modified as in 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
(Fig. 
<figureCitation captionStart="Figure 11" captionStartId="F11" captionText="Figure 11. Mysidetes illigi from ice cave of Bernard Island, Antarctica. Adult females BL 18.4 mm (A, C, E), 18.1 mm (B, D) A labrum, ventral aspect B mandibles with right palp, rostral C labium D maxillula, caudal E maxilla, caudal." figureDoi="10.3897/zookeys.1079.76412.figure11" httpUri="https://binary.pensoft.net/fig/629321" pageId="0" pageNumber="145">11B</figureCitation>
), its digitus mobilis small with one large and 3-4 very small teeth, pars centralis distally with one thick spiny tooth and proximally with 3-5 acute teeth projecting from a common basis. Pars molaris with well-developed grinding surface in both mandibles.
</paragraph>
<paragraph pageId="0" pageNumber="145">
Labrum and labium as described above for 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">
<emphasis italics="true" pageId="0" pageNumber="145">Maxillula</emphasis>
.
</emphasis>
Distal segment of maxillula terminally with 12-14 strong spines, in part serrated by small denticles in median portions. No such denticles on the largest spine in innermost (mesial) position. Distal segment subterminally with 8-9 barbed setae, of which 7-8 setae densely set in transverse, linear series; 0-2 pore near outermost seta; the remaining 1-2 setae positioned a short distance proximally, out of series. All these setae with barb patterns as in 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
. Endite of maxillula terminally with three distally spiny setae accompanied by four proximally thick barbed setae; mesial and lateral margins of endite with numerous less thick setae; innermost seta not longest and not projecting mesially as in 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Maxilla</emphasis>
normal, densely setose, with various types of setae, but no spines or teeth. Terminal segment of endopod and sympod including its three large endites, with densely setose distal margins. The leaf-like exopod extends to distal margin of basal segment of endopod or shortly beyond. Exopod with 22-25 barbed setae all along lateral margin, the two apical setae longer and thicker than the remaining ones. Basal segment of endopod with three basally thick, barbed setae. Terminal segment 1.3-1.5 times longer than wide; setae along its lateral margin resembling acute spines, but characterised as modified setae rather than spines based on the densely barbed basal half. Mesial margin of sympod with long seta micro-serrated by minute stiff bristles along its distal third; this seta extending beyond dense brush of plumose setae.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Foregut</emphasis>
(Fig. 
<figureCitation captionStart="Figure 18" captionStartId="F18" captionText="Figure 18. Cardiac portion of foregut in Mysidetes hanseni from ice cave of Curie Islands, Antarctica; pyloric parts removed. Adult female BL 23.4 mm. A foregut in slightly oblique lateral view, lower-case labels indicate dorsolateral infoldings (di), lateralia (la), mid-gut (mg), esophagus (oe), pigment bodies (pb), and storage space (sp) B spine from dorsolateral infoldings C spinose lobe of posterior part of lateralia D, E spines from anterior parts of lateralia." figureDoi="10.3897/zookeys.1079.76412.figure18" httpUri="https://binary.pensoft.net/fig/629328" pageId="0" pageNumber="145">18</figureCitation>
). Spines on most of the lateralia as in 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
, except for modified spines in Figs 
<figureCitation captionStart="Figure 18" captionStartId="F18" captionText="Figure 18. Cardiac portion of foregut in Mysidetes hanseni from ice cave of Curie Islands, Antarctica; pyloric parts removed. Adult female BL 23.4 mm. A foregut in slightly oblique lateral view, lower-case labels indicate dorsolateral infoldings (di), lateralia (la), mid-gut (mg), esophagus (oe), pigment bodies (pb), and storage space (sp) B spine from dorsolateral infoldings C spinose lobe of posterior part of lateralia D, E spines from anterior parts of lateralia." figureDoi="10.3897/zookeys.1079.76412.figure18" httpUri="https://binary.pensoft.net/fig/629328" pageId="0" pageNumber="145">18B and C</figureCitation>
. Posterior part of lateralia on each side of foregut with lobe bearing dense set of 10-14 bilaterally serrated spines (Fig. 
<figureCitation captionStart="Figure 18" captionStartId="F18" captionText="Figure 18. Cardiac portion of foregut in Mysidetes hanseni from ice cave of Curie Islands, Antarctica; pyloric parts removed. Adult female BL 23.4 mm. A foregut in slightly oblique lateral view, lower-case labels indicate dorsolateral infoldings (di), lateralia (la), mid-gut (mg), esophagus (oe), pigment bodies (pb), and storage space (sp) B spine from dorsolateral infoldings C spinose lobe of posterior part of lateralia D, E spines from anterior parts of lateralia." figureDoi="10.3897/zookeys.1079.76412.figure18" httpUri="https://binary.pensoft.net/fig/629328" pageId="0" pageNumber="145">18C</figureCitation>
). Dorsolateral infoldings on each side with two strong spines, unilaterally serrated in median to subapical portions (Fig. 
<figureCitation captionStart="Figure 18" captionStartId="F18" captionText="Figure 18. Cardiac portion of foregut in Mysidetes hanseni from ice cave of Curie Islands, Antarctica; pyloric parts removed. Adult female BL 23.4 mm. A foregut in slightly oblique lateral view, lower-case labels indicate dorsolateral infoldings (di), lateralia (la), mid-gut (mg), esophagus (oe), pigment bodies (pb), and storage space (sp) B spine from dorsolateral infoldings C spinose lobe of posterior part of lateralia D, E spines from anterior parts of lateralia." figureDoi="10.3897/zookeys.1079.76412.figure18" httpUri="https://binary.pensoft.net/fig/629328" pageId="0" pageNumber="145">18B</figureCitation>
). Dorsal and rostral portions of foregut furnished outside with large numbers of pigment bodies.
</paragraph>
<paragraph pageId="0" pageNumber="145">
Thoracic sternites as described above for 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Thoracopods general</emphasis>
(Figs 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17G-K</figureCitation>
, 
<figureCitation captionStart="Figure 19" captionStartId="F19" captionText="Figure 19. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm. A thoracopod 8, rostral B penis C-E series of male pleopods 1, 3, 5, caudal (C, D) and rostral (E) face, many setae broken F uropods, dorsal, setae omitted G telson." figureDoi="10.3897/zookeys.1079.76412.figure19" httpUri="https://binary.pensoft.net/fig/629329" pageId="0" pageNumber="145">19A</figureCitation>
). Exopods with variable length of flagella and basal plates, no clear size trend along series of exopods 2-7; exopod 1 shorter in both sexes; exopod 8 shorter in females, variable in males. Length of flagella 1.3-2.1 times length of basal plates. Basal plates laterally expanded, length 1.2-2.2 times width. Disto-lateral edge of plates rounded. Endopods becoming longer and more slender from endopod 1 to 5 and decreasing slightly from 5 to 8. Endopods 5-7 long and slender. Ischium becoming increasingly slender from endopods 1 to 5. Length of ischium increasing from endopods 1 to 5 and remaining subequal amongst endopods 5-8. Ischium shorter than merus in endopods 1-4, but longer than merus in endopods 5-8. Dactyli of endopods 1-3 larger than those of endopods 4-8. Claw 1 strong, weakly bent; claw 2 not developed; claws 3-4 slightly bent, equally long; claws 5-8 well or indistinctly curved, shorter than claws 3-4. First thoracopods with large, leaf-like, smooth epipod.
</paragraph>
<caption doi="10.3897/zookeys.1079.76412.figure18" httpUri="https://binary.pensoft.net/fig/629328" pageId="0" pageNumber="145" start="Figure 18" startId="F18">
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">Figure 18.</emphasis>
Cardiac portion of foregut in 
<taxonomicName authorityName="Zimmer" authorityYear="1914" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes hanseni" order="Mysidacea" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="hanseni">
<emphasis italics="true" pageId="0" pageNumber="145">Mysidetes hanseni</emphasis>
</taxonomicName>
from ice cave of Curie Islands, Antarctica; pyloric parts removed. Adult female BL 23.4 mm. 
<emphasis bold="true" pageId="0" pageNumber="145">A</emphasis>
foregut in slightly oblique lateral view, lower-case labels indicate dorsolateral infoldings (
<emphasis italics="true" pageId="0" pageNumber="145">di</emphasis>
), lateralia (
<emphasis italics="true" pageId="0" pageNumber="145">la</emphasis>
), mid-gut (
<emphasis italics="true" pageId="0" pageNumber="145">mg</emphasis>
), esophagus (
<emphasis italics="true" pageId="0" pageNumber="145">oe</emphasis>
), pigment bodies (
<emphasis italics="true" pageId="0" pageNumber="145">pb</emphasis>
), and storage space (
<emphasis italics="true" pageId="0" pageNumber="145">sp</emphasis>
) 
<emphasis bold="true" pageId="0" pageNumber="145">B</emphasis>
spine from dorsolateral infoldings 
<emphasis bold="true" pageId="0" pageNumber="145">C</emphasis>
spinose lobe of posterior part of lateralia 
<emphasis bold="true" pageId="0" pageNumber="145">D, E</emphasis>
spines from anterior parts of lateralia.
</paragraph>
</caption>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">Maxillipeds</emphasis>
. Combined praeischium plus ischium of maxilliped 2 are 0.8-0.9 times merus length. Dactylus with large numbers of normal setae and 14-17 setae modified as in 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
. Remaining features as described above for 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Marsupium</emphasis>
(Fig. 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16E</figureCitation>
). Essentially as described above for 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
, except for setae numbers and cuticle structure. Oostegite 1 near basis with about 30 micro-serrated setae, oostegite 2 with 9-12. Large oostegite 2 with cuticle sculptured by minute depressions over most of its outer surface. These structures resembling scales in episcopic view, but clearly identifiable as depressions in tangential view (both views in Fig. 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16E</figureCitation>
), visible 
<emphasis italics="true" pageId="0" pageNumber="145">in situ</emphasis>
already with 15 
<normalizedToken originalValue="×">x</normalizedToken>
episcopic inspection. Oostegite 1 with a narrow ribbon of such structures along and close to upper margin, but most of its surface with smooth cuticle, not considering setae. Thoracopod 6 with rudimentary oostegite bearing 10-13 (n = 3) apically microserrated setae.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Penes</emphasis>
(Fig. 
<figureCitation captionStart="Figure 19" captionStartId="F19" captionText="Figure 19. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm. A thoracopod 8, rostral B penis C-E series of male pleopods 1, 3, 5, caudal (C, D) and rostral (E) face, many setae broken F uropods, dorsal, setae omitted G telson." figureDoi="10.3897/zookeys.1079.76412.figure19" httpUri="https://binary.pensoft.net/fig/629329" pageId="0" pageNumber="145">19B</figureCitation>
) anteriorly bent at basis. Shaft terminally slightly widened, blunt, ending in 2-3 indistinct lobes. Penes extend anteriorly to thoracic sternites 6-7 in immatures (n = 25), to sternites 3-7 in subadults (n = 14) and to sternites 2-5 (mainly sternite 4) in adults (n = 7).
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Pleon</emphasis>
(Figs 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17L, M</figureCitation>
, 
<figureCitation captionStart="Figure 19" captionStartId="F19" captionText="Figure 19. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm. A thoracopod 8, rostral B penis C-E series of male pleopods 1, 3, 5, caudal (C, D) and rostral (E) face, many setae broken F uropods, dorsal, setae omitted G telson." figureDoi="10.3897/zookeys.1079.76412.figure19" httpUri="https://binary.pensoft.net/fig/629329" pageId="0" pageNumber="145">19C-E</figureCitation>
). Pleonites 1-5 measure 0.6-0.7, 0.6-0.8, 0.6-0.7, 0.6-0.7 and 0.6-0.7 times the length of pleonite 6, respectively, i.e. combined pleonites 4 and 5 exceed pleonite 6. Tergites 1-7 with transverse linear series of various numbers of pores as in Figs 
<figureCitation captionStart="Figure 17" captionStartId="F17" captionText="Figure 17. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm (A, C-F, I, J), adult female 23.4 mm (B, G, H, K-M) A right male antennula, dorsal B distal margin of left female antennular trunk, ventral, flagella omitted C antenna with antennal gland, dorsal, setae omitted from antennal scale D carapace expanded on slide, details show cervical (E) and cardial (F) pore groups G-K tarsus in series of thoracic endopods 2 - 5, 8, setae omitted L tergite expanded on slide together with pleurites of pleomere 1, setae of pleopods omitted, detail (M) shows transverse pore groups. E, F, M, pore diameters not to scale." figureDoi="10.3897/zookeys.1079.76412.figure17" httpUri="https://binary.pensoft.net/fig/629327" pageId="0" pageNumber="145">17L, M</figureCitation>
. Pleopod structure as described above for 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
. Pleopods of about same size in both sexes. Length decreasing from pleopod 1 to pleopod 2, remaining subequal amongst 2 and 3 and increasing from 3 to 5. Exopodal portion of pleopod 1 wider than in pleopods 2-5. Its length ranges between that of pleopods 3 and 4. Scutellum paracaudale forming a large acute triangle with slightly concave margins.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Uropods</emphasis>
(Figs 
<figureCitation captionStart="Figure 16" captionStartId="F16" captionText="Figure 16. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult females BL 23.4 mm (A, B), 21.4 mm (E); adult male 24.7 mm (C, D). A head of female, obliquely lateral B anterior body region of female, dorsal, dashed line enhances the anterior contour of carapace C anterior body region of male, lateral D tail fan, lateral E cuticle structures on outer surface of the large second oostegite." figureDoi="10.3897/zookeys.1079.76412.figure16" httpUri="https://binary.pensoft.net/fig/629326" pageId="0" pageNumber="145">16D</figureCitation>
, 
<figureCitation captionStart="Figure 19" captionStartId="F19" captionText="Figure 19. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm. A thoracopod 8, rostral B penis C-E series of male pleopods 1, 3, 5, caudal (C, D) and rostral (E) face, many setae broken F uropods, dorsal, setae omitted G telson." figureDoi="10.3897/zookeys.1079.76412.figure19" httpUri="https://binary.pensoft.net/fig/629329" pageId="0" pageNumber="145">19F</figureCitation>
). Length of exopod 1.1-1.4 times endopod and 1.1-1.4 times telson, endopod 0.9-1.0 times telson. Exopod extending 0.2-0.3 times its length beyond endopod and 0.2-0.3 times its length beyond telson, endopod 0.1-0.2 times its length beyond telson (partly due to telson inserting more rostrally). Exopod with slightly sigmoid, almost straight lateral margin and clearly convex mesial margin. Endopod basally with large statocyst containing one statolith with diameter of 178-227 
<normalizedToken originalValue="µm">µm</normalizedToken>
(n = 8 statoliths from four specimens). Statoliths discoidal, composed of the mineral fluorite. Statolith formula 3 + 1 + (4-7) + (6-7) + (5-9) = 19-23.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" italics="true" pageId="0" pageNumber="145">Telson</emphasis>
(Fig. 
<figureCitation captionStart="Figure 19" captionStartId="F19" captionText="Figure 19. Mysidetes hanseni from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm. A thoracopod 8, rostral B penis C-E series of male pleopods 1, 3, 5, caudal (C, D) and rostral (E) face, many setae broken F uropods, dorsal, setae omitted G telson." figureDoi="10.3897/zookeys.1079.76412.figure19" httpUri="https://binary.pensoft.net/fig/629329" pageId="0" pageNumber="145">19G</figureCitation>
). Length 1.2-1.3 times length of ultimate pleonite. Basal portion of lateral margins with linear series (rather than aggregated) of 2-5 spines in immatures with 9 mm body length (n = 3) and in three subadults with 11 mm length (n = 3); spine-free sub-basal portion 5-13% of telson length in immatures, 5-17% in subadults and 0-10% in adults (n = 10). Most proximal portion of each lateral margin with 3-7 crowded spines in adults; sub-basal spine-free portion, if any, distally followed by 4-8 subequal spines positioned in a nearly continuous series; median to terminal portions with 31-46 spines densely arranged in consecutive sets of 2-6 spines increasing in length distally.
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">Larvae</emphasis>
(Fig. 
<figureCitation captionStart="Figure 20" captionStartId="F20" captionText="Figure 20. Nauplioid larva of Mysidetes hanseni from ice cave of Damiers Islands, Antarctica A larva at late substage N 2, lateral B antennae and mouth field, ventral, lower-case labels indicate antennula (a 1), antenna (a 2), labrum (l) and mandibles (m) with palp (p) C tip of antennula D tip of abdomen with caudal furca, lateral. A, larva artificially separated from background; A-D are from four different specimens." figureDoi="10.3897/zookeys.1079.76412.figure20" httpUri="https://binary.pensoft.net/fig/629330" pageId="0" pageNumber="145">20</figureCitation>
). Nauplioids at substages N2 and N3 more slender than in 
<taxonomicName authorityName="S. I. Smith" authorityYear="1873" class="Malacostraca" family="Mysidae" genus="Heteromysis" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Heteromysis" order="Mysida" pageId="0" pageNumber="145" phylum="Arthropoda" rank="genus">
<emphasis italics="true" pageId="0" pageNumber="145">Heteromysis</emphasis>
</taxonomicName>
S.I. Smith, 1873 species, for example (
<bibRefCitation DOI="https://doi.org/10.5852/ejt.2021.735.1247" author="Wittmann, KJ" journalOrPublisher="European Journal of Taxonomy" pageId="0" pageNumber="145" pagination="133 - 175" refId="B114" refString="Wittmann, KJ, Abed-Navandi, D, 2021. Four new species of Heteromysis (Crustacea: Mysida) from public aquaria in Hawaii, Florida, and Western to Central Europe. European Journal of Taxonomy 735: 133 - 175, DOI: https://doi.org/10.5852/ejt.2021.735.1247" title="Four new species of Heteromysis (Crustacea: Mysida) from public aquaria in Hawaii, Florida, and Western to Central Europe." url="https://doi.org/10.5852/ejt.2021.735.1247" volume="735" year="2021">Wittmann and Abed-Navandi 2021</bibRefCitation>
). Twenty-one mounted nauplioid larvae with smooth cuticle, except for antennula, antenna and distal portions of abdomen. Antennae 1 and 2 sparsely covered with minute hairs over distal 2/3 of their length. Density of hairs increases up to tip (Fig. 
<figureCitation captionStart="Figure 20" captionStartId="F20" captionText="Figure 20. Nauplioid larva of Mysidetes hanseni from ice cave of Damiers Islands, Antarctica A larva at late substage N 2, lateral B antennae and mouth field, ventral, lower-case labels indicate antennula (a 1), antenna (a 2), labrum (l) and mandibles (m) with palp (p) C tip of antennula D tip of abdomen with caudal furca, lateral. A, larva artificially separated from background; A-D are from four different specimens." figureDoi="10.3897/zookeys.1079.76412.figure20" httpUri="https://binary.pensoft.net/fig/629330" pageId="0" pageNumber="145">20C</figureCitation>
). The old cuticle has started to separate from the tip of the antennula in Fig. 
<figureCitation captionStart="Figure 20" captionStartId="F20" captionText="Figure 20. Nauplioid larva of Mysidetes hanseni from ice cave of Damiers Islands, Antarctica A larva at late substage N 2, lateral B antennae and mouth field, ventral, lower-case labels indicate antennula (a 1), antenna (a 2), labrum (l) and mandibles (m) with palp (p) C tip of antennula D tip of abdomen with caudal furca, lateral. A, larva artificially separated from background; A-D are from four different specimens." figureDoi="10.3897/zookeys.1079.76412.figure20" httpUri="https://binary.pensoft.net/fig/629330" pageId="0" pageNumber="145">20C</figureCitation>
, therefore appearing flabby there. Antennula and antenna not yet bifid (Fig. 
<figureCitation captionStart="Figure 20" captionStartId="F20" captionText="Figure 20. Nauplioid larva of Mysidetes hanseni from ice cave of Damiers Islands, Antarctica A larva at late substage N 2, lateral B antennae and mouth field, ventral, lower-case labels indicate antennula (a 1), antenna (a 2), labrum (l) and mandibles (m) with palp (p) C tip of antennula D tip of abdomen with caudal furca, lateral. A, larva artificially separated from background; A-D are from four different specimens." figureDoi="10.3897/zookeys.1079.76412.figure20" httpUri="https://binary.pensoft.net/fig/629330" pageId="0" pageNumber="145">20B</figureCitation>
) in all N2-larvae and in most N3-larvae examined. The most striking features of the nauplioids are a pair of long cerci (Fig. 
<figureCitation captionStart="Figure 20" captionStartId="F20" captionText="Figure 20. Nauplioid larva of Mysidetes hanseni from ice cave of Damiers Islands, Antarctica A larva at late substage N 2, lateral B antennae and mouth field, ventral, lower-case labels indicate antennula (a 1), antenna (a 2), labrum (l) and mandibles (m) with palp (p) C tip of antennula D tip of abdomen with caudal furca, lateral. A, larva artificially separated from background; A-D are from four different specimens." figureDoi="10.3897/zookeys.1079.76412.figure20" httpUri="https://binary.pensoft.net/fig/629330" pageId="0" pageNumber="145">20D</figureCitation>
), together forming a comparatively large caudal furca armed by numerous spine-like setae. Such spiny setae, together with tiny hairs (as on antennae), are also present on (sub)-apical portions of abdomen. Remaining features in Fig. 
<figureCitation captionStart="Figure 20" captionStartId="F20" captionText="Figure 20. Nauplioid larva of Mysidetes hanseni from ice cave of Damiers Islands, Antarctica A larva at late substage N 2, lateral B antennae and mouth field, ventral, lower-case labels indicate antennula (a 1), antenna (a 2), labrum (l) and mandibles (m) with palp (p) C tip of antennula D tip of abdomen with caudal furca, lateral. A, larva artificially separated from background; A-D are from four different specimens." figureDoi="10.3897/zookeys.1079.76412.figure20" httpUri="https://binary.pensoft.net/fig/629330" pageId="0" pageNumber="145">20</figureCitation>
are typical for the state of development.
</paragraph>
<caption doi="10.3897/zookeys.1079.76412.figure19" httpUri="https://binary.pensoft.net/fig/629329" pageId="0" pageNumber="145" start="Figure 19" startId="F19">
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">Figure 19.</emphasis>
<taxonomicName authorityName="Zimmer" authorityYear="1914" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes hanseni" order="Mysidacea" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="hanseni">
<emphasis italics="true" pageId="0" pageNumber="145">Mysidetes hanseni</emphasis>
</taxonomicName>
from ice cave of Curie Islands, Antarctica. Adult male BL 24.7 mm. 
<emphasis bold="true" pageId="0" pageNumber="145">A</emphasis>
thoracopod 8, rostral 
<emphasis bold="true" pageId="0" pageNumber="145">B</emphasis>
penis 
<emphasis bold="true" pageId="0" pageNumber="145">C-E</emphasis>
series of male pleopods 1, 3, 5, caudal (
<emphasis bold="true" pageId="0" pageNumber="145">C, D</emphasis>
) and rostral (
<emphasis bold="true" pageId="0" pageNumber="145">E</emphasis>
) face, many setae broken 
<emphasis bold="true" pageId="0" pageNumber="145">F</emphasis>
uropods, dorsal, setae omitted 
<emphasis bold="true" pageId="0" pageNumber="145">G</emphasis>
telson.
</paragraph>
</caption>
</subSubSection>
<subSubSection pageId="0" pageNumber="145" type="distribution">
<paragraph pageId="0" pageNumber="145">Distribution and type locality.</paragraph>
<paragraph pageId="0" pageNumber="145">
Type locality is at the East-Antarctic coast, 
<geoCoordinate degrees="66" direction="south" minutes="02" orientation="latitude" precision="925" value="-66.03333">66°02'S</geoCoordinate>
, 
<geoCoordinate degrees="89" direction="east" minutes="38" orientation="longitude" precision="925" value="89.63333">89°38'E</geoCoordinate>
(details as given above for 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
). The types only there were taken in December 1902 with non-closing vertical hauls from 200-0 m (lectotype) and 250-0 m (paralectotype) below ice, bottom depth 385 m (
<bibRefCitation author="Zimmer, C" editor="Drygalski, E von" journalOrPublisher="Georg Reimer, Berlin" pageId="0" pageNumber="145" pagination="377 - 445" refId="B123" refString="Zimmer, C, 1914. Die Schizopoden der deutschen Suedpolar-Expedition 1901-1903. In: Drygalski, E von, Ed., Deutsche Suedpolar-Expedition 1901-1903, XV. Zoologie. Georg Reimer, Berlin 7: 377 - 445" title="Die Schizopoden der deutschen Suedpolar-Expedition 1901 - 1903." volume="7" volumeTitle="Deutsche Suedpolar-Expedition 1901 - 1903, XV. Zoologie." year="1914">Zimmer 1914</bibRefCitation>
). The present records from ice caves in 2-5 m depth at Curie Islands, 
<geoCoordinate degrees="66" direction="south" minutes="38.64" orientation="latitude" precision="9" value="-66.644">66°38.64'S</geoCoordinate>
, 
<geoCoordinate degrees="140" direction="east" minutes="02.43" orientation="longitude" precision="9" value="140.0405">140°02.43'E</geoCoordinate>
and in 2 m depth at Damiers Islands, 
<geoCoordinate degrees="66" direction="south" minutes="39.21" orientation="latitude" precision="9" value="-66.6535">66°39.21'S</geoCoordinate>
, 
<geoCoordinate degrees="139" direction="east" minutes="57.61" orientation="longitude" precision="9" value="139.96016">139°57.61'E</geoCoordinate>
, are from the second and third localities ever published; see also Discussion.
</paragraph>
</subSubSection>
<subSubSection pageId="0" pageNumber="145" type="distribution">
<paragraph pageId="0" pageNumber="145">Colour and microdistribution.</paragraph>
<paragraph pageId="0" pageNumber="145">
Live colour of this species was documented only in the field (Fig. 
<figureCitation captionStart="Figure 14" captionStartId="F14" captionText="Figure 14. Mysidetes hanseni in its natural habitat inside ice cave of Damiers Islands, Antarctica A adult male, dorsal B incubating female, dorsal C physical aspect of habitat." figureDoi="10.3897/zookeys.1079.76412.figure14" httpUri="https://binary.pensoft.net/fig/629324" pageId="0" pageNumber="145">14A, B</figureCitation>
). Most specimens showed a whitish tinge of body, eyes, hepatic caeca and brood pouch content. Oil globules (fat bodies) also contributed to the whitish tinge. Globules were found everywhere in the body trunk, with greatest densities above the foregut and in the telson. Comparatively small numbers of red-orange pigment spots were present on eyestalks, carapace, pleomeres, and telson. These were slightly 
<normalizedToken originalValue="‘expanded’">'expanded'</normalizedToken>
mostly on telson, partly also eyestalks. A few specimens (not documented in Fig. 
<figureCitation captionStart="Figure 14" captionStartId="F14" captionText="Figure 14. Mysidetes hanseni in its natural habitat inside ice cave of Damiers Islands, Antarctica A adult male, dorsal B incubating female, dorsal C physical aspect of habitat." figureDoi="10.3897/zookeys.1079.76412.figure14" httpUri="https://binary.pensoft.net/fig/629324" pageId="0" pageNumber="145">14</figureCitation>
) showed an overall, weakly red to orange tinge. Corneas appeared white in the field, but were brown in ethanol-fixed materials; therefore, it is not excluded that reflection had contributed to the white tinge in field photos. The mysids were encountered close to and mostly in physical contact with the substrate ice or rock surfaces, with or without epigrowth (Fig. 
<figureCitation captionStart="Figure 14" captionStartId="F14" captionText="Figure 14. Mysidetes hanseni in its natural habitat inside ice cave of Damiers Islands, Antarctica A adult male, dorsal B incubating female, dorsal C physical aspect of habitat." figureDoi="10.3897/zookeys.1079.76412.figure14" httpUri="https://binary.pensoft.net/fig/629324" pageId="0" pageNumber="145">14A, B</figureCitation>
).
</paragraph>
</subSubSection>
<subSubSection pageId="0" pageNumber="145" type="gut contents">
<paragraph pageId="0" pageNumber="145">Gut contents.</paragraph>
<paragraph pageId="0" pageNumber="145">
Upon external inspection of 49 foreguts, all appeared empty in twenty incubating females examined, all in nine spent females available and in eight out of twenty foreguts of immature males. Eight 
<normalizedToken originalValue="‘empty’">'empty'</normalizedToken>
foreguts dissected and mounted on slides showed that 0-5% volume contained food. Fig. 
<figureCitation captionStart="Figure 18" captionStartId="F18" captionText="Figure 18. Cardiac portion of foregut in Mysidetes hanseni from ice cave of Curie Islands, Antarctica; pyloric parts removed. Adult female BL 23.4 mm. A foregut in slightly oblique lateral view, lower-case labels indicate dorsolateral infoldings (di), lateralia (la), mid-gut (mg), esophagus (oe), pigment bodies (pb), and storage space (sp) B spine from dorsolateral infoldings C spinose lobe of posterior part of lateralia D, E spines from anterior parts of lateralia." figureDoi="10.3897/zookeys.1079.76412.figure18" httpUri="https://binary.pensoft.net/fig/629328" pageId="0" pageNumber="145">18</figureCitation>
gives an example of a foregut considered 
<normalizedToken originalValue="‘empty’">'empty'</normalizedToken>
upon external inspection (40'), yet with a few diatoms identified at 200 
<normalizedToken originalValue="×">x</normalizedToken>
magnification. The 12 
<normalizedToken originalValue="‘positive’">'positive'</normalizedToken>
immature males had 10-40% foregut volume filled. Contents were unidentifiable, masticated organic material (debris), cyanobacteria, diatoms, a few copepod remains and a few mineral particles.
</paragraph>
</subSubSection>
<subSubSection pageId="0" pageNumber="145" type="molecular study of ice cave mysids">
<paragraph pageId="0" pageNumber="145">Molecular study of ice cave mysids</paragraph>
<paragraph pageId="0" pageNumber="145">
Figures 
<figureCitation captionStart="Figure 21" captionStartId="F21" captionText="Figure 21. Phylogenetic placement of Pseudomma kryotroglodytum sp. nov. from Antarctic ice caves at Bernard Island, amongst the Pseudomma taxa available in DNA databases (GenBank accession numbers shown), based on 18 S rDNA. The root is the Erythropini Holmesiella affinis. Neighbour-Joining (NJ, shown here) and Maximum Likelihood (ML) reconstruction methods gave a similar topology. Bootstrap (1000 replicates) values, higher than 700, are shown at nodes (NJ / ML) in this order." figureDoi="10.3897/zookeys.1079.76412.figure21" httpUri="https://binary.pensoft.net/fig/629331" pageId="0" pageNumber="145">21</figureCitation>
, 
<figureCitation captionStart="Figure 22" captionStartId="F22" captionText="Figure 22. Distance tree (Neighbour-Joining) of mitochondrial COI sequences of Mysidetes hanseni and Mysidetes illigi specimens collected in Antarctic ice caves at Curie and Damiers Islands, Dumont d'Urville Station, rooted with Antarctomysis maxima from the same area. Most relevant Bootstrap (1000 replicates) values are shown at nodes." figureDoi="10.3897/zookeys.1079.76412.figure22" httpUri="https://binary.pensoft.net/fig/629332" pageId="0" pageNumber="145">22</figureCitation>
</paragraph>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">
Sequencing of 
<taxonomicName authorityName="Wittmann &amp; Chevaldonné" authorityYear="2021" class="Malacostraca" family="Mysidae" genus="Pseudomma" kingdom="Animalia" lsidName="Pseudomma kryotroglodytum" order="Mysidacea" pageId="0" pageNumber="145" phylum="Schizopoda" rank="species" species="kryotroglodytum">
<emphasis italics="true" pageId="0" pageNumber="145">Pseudomma kryotroglodytum</emphasis>
</taxonomicName>
sp. nov.
</emphasis>
The 18S DNA sequences obtained from the two here-described specimens of 
<taxonomicName lsidName="P. kryotroglodytum" pageId="0" pageNumber="145" rank="species" species="kryotroglodytum">
<emphasis italics="true" pageId="0" pageNumber="145">P. kryotroglodytum</emphasis>
</taxonomicName>
sp. nov. were identical and 805 bp long. COI sequences of unequal quality were obtained from both specimens and were 614 and 658 bp for individuals 611-1 (paratype) and 612-1 (holotype), respectively. Over the alignable part of these sequences, they differed by only one synonymous position. Only 18S sequences could be compared with GenBank sequences of other 
<taxonomicName authorityName="G. O. Sars" authorityYear="1870" class="Malacostraca" family="Mysidae" genus="Pseudomma" kingdom="Animalia" lsidName="Pseudomma" order="Mysidacea" pageId="0" pageNumber="145" phylum="Schizopoda" rank="genus">
<emphasis italics="true" pageId="0" pageNumber="145">Pseudomma</emphasis>
</taxonomicName>
species. We aligned our sequences with 18 available GenBank sequences and obtained NJ and ML phylogenetic trees (Fig. 
<figureCitation captionStart="Figure 21" captionStartId="F21" captionText="Figure 21. Phylogenetic placement of Pseudomma kryotroglodytum sp. nov. from Antarctic ice caves at Bernard Island, amongst the Pseudomma taxa available in DNA databases (GenBank accession numbers shown), based on 18 S rDNA. The root is the Erythropini Holmesiella affinis. Neighbour-Joining (NJ, shown here) and Maximum Likelihood (ML) reconstruction methods gave a similar topology. Bootstrap (1000 replicates) values, higher than 700, are shown at nodes (NJ / ML) in this order." figureDoi="10.3897/zookeys.1079.76412.figure21" httpUri="https://binary.pensoft.net/fig/629331" pageId="0" pageNumber="145">21</figureCitation>
) of similar topologies (only NJ shown), rooted with 
<taxonomicName authorityName="Ii" authorityYear="1937" class="Malacostraca" family="Mysidae" genus="Holmesiella" kingdom="Animalia" lsidName="Holmesiella affinis" order="Mysida" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="affinis">
<emphasis italics="true" pageId="0" pageNumber="145">Holmesiella affinis</emphasis>
</taxonomicName>
Ii, 1937 and bootstrapped (1000 replicates for each method). Not even half of the 
<taxonomicName authorityName="G. O. Sars" authorityYear="1870" class="Malacostraca" family="Mysidae" genus="Pseudomma" kingdom="Animalia" lsidName="Pseudomma" order="Mysidacea" pageId="0" pageNumber="145" phylum="Schizopoda" rank="genus">
<emphasis italics="true" pageId="0" pageNumber="145">Pseudomma</emphasis>
</taxonomicName>
species described to date are shown in this tree and only one Southern Ocean species (
<taxonomicName lsidName="P. sarsii" pageId="0" pageNumber="145" rank="species" species="sarsii">
<emphasis italics="true" pageId="0" pageNumber="145">P. sarsii</emphasis>
</taxonomicName>
) is available for comparison, but 
<taxonomicName lsidName="P. kryotroglodytum" pageId="0" pageNumber="145" rank="species" species="kryotroglodytum">
<emphasis italics="true" pageId="0" pageNumber="145">P. kryotroglodytum</emphasis>
</taxonomicName>
sp. nov. is molecularly different from every other one in the tree. Bootstrap support is poor for most relevant nodes, but two species appear more closely related to 
<taxonomicName lsidName="P. kryotroglodytum" pageId="0" pageNumber="145" rank="species" species="kryotroglodytum">
<emphasis italics="true" pageId="0" pageNumber="145">P. kryotroglodytum</emphasis>
</taxonomicName>
sp. nov. in this dataset: 
<taxonomicName lsidName="P. longisquamosum" pageId="0" pageNumber="145" rank="species" species="longisquamosum">
<emphasis italics="true" pageId="0" pageNumber="145">P. longisquamosum</emphasis>
</taxonomicName>
Murano, 1974 and 
<taxonomicName lsidName="P. maasakii" pageId="0" pageNumber="145" rank="species" species="maasakii">
<emphasis italics="true" pageId="0" pageNumber="145">P. maasakii</emphasis>
</taxonomicName>
Meland &amp; Brattegard, 2007.
</paragraph>
<caption doi="10.3897/zookeys.1079.76412.figure20" httpUri="https://binary.pensoft.net/fig/629330" pageId="0" pageNumber="145" start="Figure 20" startId="F20">
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">Figure 20.</emphasis>
Nauplioid larva of 
<taxonomicName authorityName="Zimmer" authorityYear="1914" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes hanseni" order="Mysidacea" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="hanseni">
<emphasis italics="true" pageId="0" pageNumber="145">Mysidetes hanseni</emphasis>
</taxonomicName>
from ice cave of Damiers Islands, Antarctica 
<emphasis bold="true" pageId="0" pageNumber="145">A</emphasis>
larva at late substage N2, lateral 
<emphasis bold="true" pageId="0" pageNumber="145">B</emphasis>
antennae and mouth field, ventral, lower-case labels indicate antennula (
<emphasis italics="true" pageId="0" pageNumber="145">a1</emphasis>
), antenna (
<emphasis italics="true" pageId="0" pageNumber="145">a2</emphasis>
), labrum (
<emphasis italics="true" pageId="0" pageNumber="145">l</emphasis>
) and mandibles (
<emphasis italics="true" pageId="0" pageNumber="145">m</emphasis>
) with palp (
<emphasis italics="true" pageId="0" pageNumber="145">p</emphasis>
) 
<emphasis bold="true" pageId="0" pageNumber="145">C</emphasis>
tip of antennula 
<emphasis bold="true" pageId="0" pageNumber="145">D</emphasis>
tip of abdomen with caudal furca, lateral. 
<emphasis bold="true" pageId="0" pageNumber="145">A</emphasis>
, larva artificially separated from background; 
<emphasis bold="true" pageId="0" pageNumber="145">A-D</emphasis>
are from four different specimens.
</paragraph>
</caption>
<paragraph pageId="0" pageNumber="145">
<emphasis bold="true" pageId="0" pageNumber="145">
Sequencing of 
<taxonomicName authorityName="Zimmer" authorityYear="1914" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes illigi" order="Mysidacea" pageId="0" pageNumber="145" phylum="Arthropoda" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">Mysidetes illigi</emphasis>
</taxonomicName>
and 
<taxonomicName lsidName="M. hanseni." pageId="0" pageNumber="145" rank="species" species="hanseni.">
<emphasis italics="true" pageId="0" pageNumber="145">M. hanseni.</emphasis>
</taxonomicName>
</emphasis>
A total of six individuals of 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
from Bernard Island and 10 
<taxonomicName lsidName="M. hanseni" pageId="0" pageNumber="145" rank="species" species="hanseni">
<emphasis italics="true" pageId="0" pageNumber="145">M. hanseni</emphasis>
</taxonomicName>
from Damiers and Curie Islands were sequenced at both the COI and 18S loci. No comparison with GenBank was possible because this is the first time 
<taxonomicName authorityName="Holt &amp; Tattersall" authorityYear="1906" class="Malacostraca" family="Mysidae" genus="Mysidetes" higherTaxonomySource="CoL" kingdom="Animalia" lsidName="Mysidetes" order="Mysidacea" pageId="0" pageNumber="145" phylum="Arthropoda" rank="genus">
<emphasis italics="true" pageId="0" pageNumber="145">Mysidetes</emphasis>
</taxonomicName>
sequences are made available. The 18S sequences obtained were 815 and 813 bp long for 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
and 
<taxonomicName lsidName="M. hanseni" pageId="0" pageNumber="145" rank="species" species="hanseni">
<emphasis italics="true" pageId="0" pageNumber="145">M. hanseni</emphasis>
</taxonomicName>
, respectively. No differences were observed at this 18S fragment within species, whereas there was a 6 bp difference (but no indel) between the two species. COI sequences of variable quality were obtained (658 to 629 bp), of which 629 bp could be aligned. A simple distance tree (NJ) was produced to visualise the differences and similarities amongst sequences (rooted with 
<taxonomicName lsidName="A. maxima" pageId="0" pageNumber="145" rank="species" species="maxima">
<emphasis italics="true" pageId="0" pageNumber="145">A. maxima</emphasis>
</taxonomicName>
). As evident on Fig. 
<figureCitation captionStart="Figure 22" captionStartId="F22" captionText="Figure 22. Distance tree (Neighbour-Joining) of mitochondrial COI sequences of Mysidetes hanseni and Mysidetes illigi specimens collected in Antarctic ice caves at Curie and Damiers Islands, Dumont d'Urville Station, rooted with Antarctomysis maxima from the same area. Most relevant Bootstrap (1000 replicates) values are shown at nodes." figureDoi="10.3897/zookeys.1079.76412.figure22" httpUri="https://binary.pensoft.net/fig/629332" pageId="0" pageNumber="145">22</figureCitation>
, the 
<taxonomicName lsidName="M. hanseni" pageId="0" pageNumber="145" rank="species" species="hanseni">
<emphasis italics="true" pageId="0" pageNumber="145">M. hanseni</emphasis>
</taxonomicName>
sequences are quite diverse (each specimen displays a distinct haplotype), but the Damiers and Curie specimens are mixed, indicating that no apparent genetic structuring exists at this locus and this geographical scale (3.8 km). In contrast, the Bernard Island 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
sequences cluster in two divergent groups, which cannot be related either to morphological differences or to collection date and station. The divergence between the two groups is ca. 10% - a high value for intraspecific comparisons, but quite low if they were different species. As noted above, 18S is identical between the two 
<taxonomicName lsidName="M. illigi" pageId="0" pageNumber="145" rank="species" species="illigi">
<emphasis italics="true" pageId="0" pageNumber="145">M. illigi</emphasis>
</taxonomicName>
clusters, as is their translated COI amino acid sequence.
</paragraph>
</subSubSection>
</treatment>
</subSection>
</document>