<documentid="8AD3F95F1A90687CE2240182FA0AB734"ID-DOI="10.3897/BDJ.12.e121508"ID-PMC="PMC11134053"ID-PubMed="38812888"ID-ZooBank="ACAFF6E1-94C5-4D4A-9FA2-5BB0D2E494DB"ID-manuscript="24404"ID-publisher-id="121508"URI-arpha="6D478A03-351A-5B84-B22D-DF71552C1D25"URI-zoobank="ACAFF6E1-94C5-4D4A-9FA2-5BB0D2E494DB"XM.bibliography_approvedBy="admin"XM.taxonomicNames_approvedBy="admin"XM.treatmentCitations_approvedBy="admin"XM.treatments_approvedBy="admin"article-type="research-article"checkinTime="1716281014896"checkinUser="pensoft"docAuthor="Riehl, Torben, Schienbein, Katharina Ellen & Mifsud, Constantine"docDate="2024"docId="A64CDA30322C57E0B756170F03C53113"docLanguage="en"docName="BiodivDatJour 12: e121508"docOrigin="Biodiversity Data Journal 12"docSource="https://bdj.pensoft.net/article/121508/download/xml/"docStyle="DocumentStyle:PensoftTaxPub.0000.journal_article.bdj"docStyleName="PensoftTaxPub.0000.journal_article.bdj"docTitle="Mexicope maletensis Riehl & Schienbein & Mifsud 2024, sp. nov."docType="treatment"docUuid="049ED44F-A900-47AE-A386-0126ACF7061A"docUuidSource="ZooBank"docVersion="2"masterDocId="6D478A03351A5B84B22DDF71552C1D25"masterDocTitle="A new species of Mexicope Hooker, 1985 (Crustacea, Isopoda) — the first record of Acanthaspidiidae Menzies, 1962 from the Mediterranean Sea"masterLastPageNumber="e 121508"masterPageNumber="e 121508"pageNumber="e121508"updateTime="1717541638890"updateUser="ExternalLinkService">
<mods:titleid="C4FEEA419E1EC5FC2E4CF89730B6539C">A new species of Mexicope Hooker, 1985 (Crustacea, Isopoda) — the first record of Acanthaspidiidae Menzies, 1962 from the Mediterranean Sea</mods:title>
<mods:affiliationid="6DE3575531225BEDE8152781C4EC1E3A">Senckenberg Gesellschaft für Naturforschung, Frankfurt, Germany & Senckenberg Research Institute and Natural History Museum, Frankfurt am Main, Germany & Johann Wolfgang Goethe University Frankfurt, Frankfurt am Main, Germany</mods:affiliation>
<mods:affiliationid="33BAB0E5C7DB263952CAAE1644FBBB5E">Johann Wolfgang Goethe University Frankfurt, Department of Biological Sciences, Institute of Ecology, Evolution and Diversity, Frankfurt am Main, Germany</mods:affiliation>
<taxonomicNameid="C5CF5B610E3ED557F0D26B37D9F9B5DE"ID-CoL="CG3MF"authority="Riehl & Schienbein"authorityName="Riehl & Schienbein & Mifsud"authorityYear="2024"class="Malacostraca"family="Acanthaspidiidae"genus="Mexicope"kingdom="Animalia"order="Isopoda"phylum="Arthropoda"rank="species"species="maletensis"status="sp. nov.">
<materialsCitationid="5AD843E1AFEBA193553E704295F86B4A"collectingDate="2017-06-07"collectingMethod="custom-built rectangular dredge, 1 m wide, 20 cm high and with 500 µm mesh size"determinerName="torben riehl, katharina e. schienbein"latitude="35.933567"location="off Ġnejna Bay"longitude="14.322083"matCitId="58a3b6cc-79d2-5622-b2fa-a132124bdce7"originalDetermination="mexicope maletensis riehl and schienbein"specimenCode="smf 62000"specimenCount="1"specimenCount-male="1"typeStatus="holotype">
<taxonomicNameid="7BCD4B89DFD78157A0ED7C81A622017F"authority="Riehl and Schienbein"authorityName="Riehl and Schienbein"class="Malacostraca"family="Acanthaspidiidae"genus="Mexicope"kingdom="Animalia"order="Isopoda"phylum="Arthropoda"rank="species"species="maletensis">
<named-contentid="54A869569825CC81831EDBE3D088F461"content-type="dwc:scientificNameAuthorship"xlink_type="simple">Riehl & Schienbein</named-content>
<collectingMethodid="E0E629FBE8263A65CAB3D389DD137841">custom-built rectangular dredge, 1 m wide, 20 cm high and with 500 µm mesh size</collectingMethod>
<figureCitationid="79EAE16CE7B1960268FC73626E3E5487"captionStart="Figure 3"captionStartId="F11189733"captionText="Figure 3. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of antennula and antenna: A antenna; B antennula, in situ. Scale bar = 0.5 mm."figureDoi="10.3897/BDJ.12.e121508.figure3"httpUri="https://binary.pensoft.net/fig/985842">3</figureCitation>
<figureCitationid="9CCD516B0FA006C192D83287C4541C9A"captionStart="Figure 3"captionStartId="F11189733"captionText="Figure 3. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of antennula and antenna: A antenna; B antennula, in situ. Scale bar = 0.5 mm."figureDoi="10.3897/BDJ.12.e121508.figure3"httpUri="https://binary.pensoft.net/fig/985842">3</figureCitation>
A) length 0.80 body length. Article 4 distally with 5 simple setae. Article 5 longer than proximal 4 articles together, dorsal margin with 4 simple, long setae, ventral margin distally with 1 simple seta, 1 seta broken, missing. Article 6 length 1.1 article 5 length, with 19 long, simple setae, 3 broom setae. Flagellum with 12–13 articles; first article as long as carpus (peduncular article 6), length 1.4 joint length of flagellum articles 2–12, rich in aesthetascs. Aesthetascs narrow, tubular.
<figureCitationid="234B2267BDD5AAAF2BCAA82ADF9C51F0"captionStart="Figure 4"captionStartId="F11189735"captionText="Figure 4. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of mouthparts: A left and right mandibles left maxilliped, dorsal aspect; B maxillula; C maxilla; D right mandible; E right maxilliped, ventral aspect. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure4"httpUri="https://binary.pensoft.net/fig/985843">4</figureCitation>
C and D) slender, length 0.20 width, incisor of left and right Md with 5 cusps.
with 4 cusps. Spine row of left and right Md with 6 denticulate spine-like setae, progressively increasing in length and number of denticles from distal to proximal end of spine row.
<figureCitationid="27FC0015A6F79F295880A624C45F260A"captionStart="Figure 4"captionStartId="F11189735"captionText="Figure 4. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of mouthparts: A left and right mandibles left maxilliped, dorsal aspect; B maxillula; C maxilla; D right mandible; E right maxilliped, ventral aspect. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure4"httpUri="https://binary.pensoft.net/fig/985843">4</figureCitation>
F) exopod length 5.7 width; margin with row of 12 simple setae, apex obliquely truncate, with 15 spine-like setae; endopod length 0.83 exopod length, length 8.3 width, medial margin with a row of 8 long, simple setae, apex narrow, with 1 serrated, spine-like and 2 simple, spine-like seta.
<figureCitationid="F5A88AA8C6327F15AE57F209CBC5A127"captionStart="Figure 4"captionStartId="F11189735"captionText="Figure 4. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of mouthparts: A left and right mandibles left maxilliped, dorsal aspect; B maxillula; C maxilla; D right mandible; E right maxilliped, ventral aspect. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure4"httpUri="https://binary.pensoft.net/fig/985843">4</figureCitation>
E) both parts of exopod laterally flexed, exopod length 1.1 endopod length, lateral part slightly longer than mesial part; lateral part apex with 1 long, serrated and 3 simple, spine-like setae; mesial part apex with 3 long, serrated spine-like and 1 simple, spine-like setae; endopod slightly wider than mesial and lateral part of exopod, densely covered with long, simple setae, apically with 3 serrated, spine-like setae.
<figureCitationid="A15F2A0CA1EEAFC97E2F969B842FEFB5"captionStart="Figure 4"captionStartId="F11189735"captionText="Figure 4. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of mouthparts: A left and right mandibles left maxilliped, dorsal aspect; B maxillula; C maxilla; D right mandible; E right maxilliped, ventral aspect. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure4"httpUri="https://binary.pensoft.net/fig/985843">4</figureCitation>
A, B and Fig.
<figureCitationid="CAFE97165F849E36202436AADE0956DB"captionStart="Figure 5"captionStartId="F11189737"captionText="Figure 5. Mexicope maletensis sp. nov. male holotype (SMF 62000), confocal laser scanning microscopy (cLSM) images of mouthparts: A left maxilliped, dorsal aspect; B right maxilliped, ventral aspect; A left mandible; B right mandible; C maxilla; D maxillula. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure5"httpUri="https://binary.pensoft.net/fig/985844">5</figureCitation>
) length 0.21 body length; basis and endite wide, basis length (excluding endite) 1.5 width, asetose, 2
<figureCitationid="2310BF8109917FFFC76FEEE4D49D2382"captionStart="Figure 6"captionStartId="F11189739"captionText="Figure 6. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of anterior pereopods in lateral view: A pereopod I; B pereopod II; C pereopod III. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure6"httpUri="https://binary.pensoft.net/fig/985845">6</figureCitation>
,
<figureCitationid="292B9852FB17444FD2ACCB4C1C9D019C"captionStart="Figure 7"captionStartId="F11189741"captionText="Figure 7. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of posterior pereopods in lateral view: A pereopod IV; B pereopod V; C pereopod VI. Scale bar 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure7"httpUri="https://binary.pensoft.net/fig/985846">7</figureCitation>
,
<figureCitationid="B88D134FD1C433B658D2264F477720D3"captionStart="Figure 8"captionStartId="F11189743"captionText="Figure 8. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of seventh pereopods in lateral view: A right pereopod VII; B left pereopod VII; C simple (asetulate) seta; D whip seta; E robust seta; F unequally bifid (sensillate) seta; G broom seta (distal half of shaft setulate, pappose); H broom seta (apically setulate, pappose); I simple sensilla (shaft subcylindrical, tip rounded); J fringed sensilla (shaft subcylindrical, distally densely covered by small scales, tip rounded). Scale bar (A – B) = 250 µm (C – I not to scale)."figureDoi="10.3897/BDJ.12.e121508.figure8"httpUri="https://binary.pensoft.net/fig/985847">8</figureCitation>
) uniformly baculiform, ambulatory legs, length PI <II> III <IV <V <VI> VII, PII length 0.60 body length, PVI length 0.70 body length; carpi and propodi similarly long, ventral margins distodorsally with row of 1–4 robust
<collectionCodeid="267B36E204030612496ECD797973859E"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
setae; propodi distodorsally with 1 unequally bifid, spine-like seta; dactyli with 1 fringed sensilla between claws, distodorsal claw about half as long as dactylus, slender and acute, curved ventrally, distoventral claw length 0.80 distodorsal claw length or shorter.
<figureCitationid="3A7ACAF11209511E6D9402C506481C69"captionStart="Figure 6"captionStartId="F11189739"captionText="Figure 6. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of anterior pereopods in lateral view: A pereopod I; B pereopod II; C pereopod III. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure6"httpUri="https://binary.pensoft.net/fig/985845">6</figureCitation>
A) basis proximally with 1 submarginal whip seta; ischium dorsal margin with 2 whip setae, ventral margin with 1 whip seta; merus dorsal margin with 1 simple seta, ventral margin with 2 whip setae, mediodorsally with 1 simple seta; carpus dorsal margin medially with 1 whip seta, distally with 2 whip setae; ventral margin with 6 setae: 3 simple, 2 robust
<collectionCodeid="8917D2A3D578DB1ADC54C23F1822BF39"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
setae, 1 seta broken, missing; ventrally-submarginally with 2 simple setae; propodus dorsal margin medially with 1 robust
<collectionCodeid="EA7CCB07EC5574FACEB28AA24864699D"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
seta, distally with batch of 1 broom seta and 2 whip setae; ventral margin with 3 robust
<collectionCodeid="98358E5D190224985302D2524331F27B"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
setae and 1 whip seta; ventrally submarginally medially and laterally with, respectively, 1 simple seta, distolaterally with 1 simple seta; dactylus with 2 whip setae distodorsally.
<figureCitationid="042ECFA27D09AE2872C3648DDC1B0A94"captionStart="Figure 6"captionStartId="F11189739"captionText="Figure 6. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of anterior pereopods in lateral view: A pereopod I; B pereopod II; C pereopod III. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure6"httpUri="https://binary.pensoft.net/fig/985845">6</figureCitation>
B) basis dorsal margin proximally with 1 broom seta; distoventrally with 1 whip seta; ischium dorsal margin with 1 seta, broken; ventral margin with 2 whip setae; distal margin anteriorly and posteriorly respectively with 1 simple seta; merus dorsal margin proximally with 1 whip seta, distally with 2 whip setae; ventral margin with 2 whip setae; distally submarginally with 1 simple seta; carpus dorsal margin with 4 setae: 3 whip setae, 1 broom seta; distally submarginally with 2 simple setae, laterally and medially, respectively; ventral margin with 3 setae: 1 whip, 2
<collectionCodeid="4FA2CED405ED5DA549A94287B2004480"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
; propodus dorsal margin with 5 whip setae; ventral margin medially with 3
<collectionCodeid="05BD16DDF40D7432516B9448B25CD4A0"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
setae, distally with 2 whip setae; distally submarginally with 1 whip seta; dactylus dorsally subdistally with 3 whip setae, ventrally submarginally with 1 whip seta.
<figureCitationid="5BF134982972FA9EB02A40D9BC1DAB39"captionStart="Figure 6"captionStartId="F11189739"captionText="Figure 6. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of anterior pereopods in lateral view: A pereopod I; B pereopod II; C pereopod III. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure6"httpUri="https://binary.pensoft.net/fig/985845">6</figureCitation>
C) basis dorsal margin with 1 whip seta and 1 broom seta; ventral margin with 3 simple setae; ischium dorsal margin with 1 simple seta, distal margin anteriorly and posteriorly, respectively, with 1 whip seta; ventral margin with 2 whip setae; merus dorsal margin distally with 1 simple seta; ventral margin distally with 1 simple seta; distal margin posteriorly with 1 whip seta; carpus dorsal margin distally with 1 broom seta; ventral margin medially with 1 whip seta, 1 robust
<collectionCodeid="505CFEA4E00CB7B45D007BAE64A464FF"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
seta, distal margin anteriorly and posteriorly, respectively, with 1 whip seta; medially submarginally with 2 simple setae, anteriorly and posteriorly, respectively; propodus dorsal margin medially with 1 seta, broken, missing, distally with 1 simple seta; ventral margin medially with 1 robust
<collectionCodeid="9BA84C487F534A5D0C83F2CA5E380D62"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
seta, distally with 1 robust
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, 1 whip seta; dactylus dorsal margin with 4 whip setae; distally anteriorly with 2 setae, broken, missing.
<figureCitationid="00F9046434DE5D387EF82122C80574A5"captionStart="Figure 7"captionStartId="F11189741"captionText="Figure 7. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of posterior pereopods in lateral view: A pereopod IV; B pereopod V; C pereopod VI. Scale bar 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure7"httpUri="https://binary.pensoft.net/fig/985846">7</figureCitation>
A) basis proximodorsally with 1 simple seta, distoventrally with 1 simple seta; ischium dorsally with 2 simple setae submarginally; merus distodorsally with 2 simple setae; ventral margin proximally with 1 simple seta, distally with simple setae; carpus dorsal margin medially with 1 simple seta, distally with 2 simple setae, 1 broom seta, 1 seta, broken, missing; ventral margin medially with 1 simple seta, 2 robust
<collectionCodeid="81E0A2FA1D81B01FE70941165B943F56"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
setae; distal margin with 3 simple setae; propodus dorsal margin with 1 whip, 1 robust
<collectionCodeid="78767B188EC315602FE70B0FD673C8F0"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
, 1 broom seta; ventral margin with 3 robust
<collectionCodeid="2657D49972199E129AEE76867F9970BC"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
setae; dactylus dorsal margin with row of 3 simple setae and 1
<collectionCodeid="628F5B2F80353FF4DCC7137FEB2CE570"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
<figureCitationid="7216BEC35DA3E9FD628B0935350EF034"captionStart="Figure 7"captionStartId="F11189741"captionText="Figure 7. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of posterior pereopods in lateral view: A pereopod IV; B pereopod V; C pereopod VI. Scale bar 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure7"httpUri="https://binary.pensoft.net/fig/985846">7</figureCitation>
B) basis dorsal margin with 1 broom seta, 2 setae, broken, missing; ventral margin with 3 whip setae, distal margin with 1 simple seta; ischium dorsal and ventral margins with 2 whip setae, respectively; distal margin with 2 whip setae; merus dorsal margin distally with 1 whip seta, submarginally medially with 1 seta, broken, missing and 1 simple seta, distally with 1 simple seta; ventral margin proximally with 1 simple seta, distally with 1 whip seta and 1 simple seta; carpus dorsal margin medially with 2 whip setae, distally with 2 whip setae and 1 broom seta; ventral margin with 1 robust seta and 3 robust
<collectionCodeid="30386E82189B6BB2DD4D342E7825D520"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
setae; distal margin posteriorly with 1 simple seta; propodus dorsal margin with 1 robust
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seta, 5 simple setae and 1 broken seta; ventral margin proximally with 1 seta, broken, missing, 3
<collectionCodeid="229CED3CDAFA192DCB43123AC966FFC1"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
setae, submarginally with 3 whip setae; dactylus distally with 5 whip setae.
<figureCitationid="4BDB272D9843489971DB8558268F405B"captionStart="Figure 7"captionStartId="F11189741"captionText="Figure 7. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of posterior pereopods in lateral view: A pereopod IV; B pereopod V; C pereopod VI. Scale bar 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure7"httpUri="https://binary.pensoft.net/fig/985846">7</figureCitation>
C) basis dorsal margin proximally with 4 short whip setae, medially with 1 seta, broken, missing, distally with 2 robust whip setae; ventral margin distally with 1 whip seta; distal margin anteriorly with 1 whip seta; ischium dorsal margin proximally and distally with 1 simple seta, respectively; ventral margin with 3 whip setae; distal margin with 1 short whip seta anteriorly and posteriorly, respectively; merus dorsal margin distally with 1 long whip seta, medially submarginally with 1 simple seta; ventral margin proximally with 1 whip seta, distally with 1 simple seta, medially submarginally with 1 simple seta; distal margin with 1 whip seta anteriorly and 1
<collectionCodeid="8FD83692D78766B7DC6777940459327E"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
seta posteriorly; carpus dorsal margin medially with 2 broken setae, missing and 1 whip seta, distally with 3 whip setae and 1 broom seta; ventral margin with 4 robust
<collectionCodeid="7054BF80A745FA39457D6194079C6F25"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
setae, submarginally with 2 short whip setae; distal margin posteriorly with 1 simple seta; propodus dorsal margin with 3 simple setae, 2 long simple setae, 1 broom seta, 2 broken setae (missing), mesially with 4 simple setae, distodorsally with 1 robust
<collectionCodeid="8898E27AE4D7BFE9C7DAB62CB43BE4BA"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
<figureCitationid="1456392945591D05D6EB1FE419FAF746"captionStart="Figure 8"captionStartId="F11189743"captionText="Figure 8. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of seventh pereopods in lateral view: A right pereopod VII; B left pereopod VII; C simple (asetulate) seta; D whip seta; E robust seta; F unequally bifid (sensillate) seta; G broom seta (distal half of shaft setulate, pappose); H broom seta (apically setulate, pappose); I simple sensilla (shaft subcylindrical, tip rounded); J fringed sensilla (shaft subcylindrical, distally densely covered by small scales, tip rounded). Scale bar (A – B) = 250 µm (C – I not to scale)."figureDoi="10.3897/BDJ.12.e121508.figure8"httpUri="https://binary.pensoft.net/fig/985847">8</figureCitation>
A and B) basis distodorsally with 1 short whip seta; proximoventrally with 1 simple seta and distoventrally with 1 short whip seta; ischium dorsal margin with 3 whip setae, submarginally with 1 short simple seta; ventral margin with 2 simple setae; merus dorsal margin medially with 1 short whip seta, distally with 1 long simple seta; ventral margin proximally with 1 whip seta, medially submarginally with 1 simple seta, distally with 2 long whip setae; distal margin anteriorly with 1 whip seta; carpus dorsal margin with medially with 2 whip setae, distally with 1 broom seta, 2 simple setae, 1
<collectionCodeid="472C362E31B9171A371FD5ECCB7D8C9C"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
seta, 2 broken setae (missing), ventral margin with 4 robust
<collectionCodeid="BFD4C19D3495EB6949A1701B6F4A54FC"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
setae, submarginally with 3 whip setae; propodus dorsal margin medially with 2 broken setae (missing), distally with 4 long whip setae and 1 broom seta, on right PVII with 1
<collectionCodeid="78EFEA16F20D242A455401BD23946E9D"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
seta; ventral margin with 4 robust
<collectionCodeid="9C7CF509F116CEDDA687076702892930"country="France"name="Laboratoire de Biostratigraphie">UB</collectionCode>
setae, submarginally with 5 whip setae; dactylus distally with 5 whip setae.
<figureCitationid="39691BA55741437F1D5CEB7310EE0FD3"captionStart="Figure 9"captionStartId="F11189745"captionText="Figure 9. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings pleopods: A pleotelson in ventral view, uropodal setae omitted; B pleopod I; C pleopods III and IV (underneath); D pleopod II. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure9"httpUri="https://binary.pensoft.net/fig/985848">9</figureCitation>
B, Fig.
<figureCitationid="B8E025D07F71F4FC17897ABFB984750B"captionStart="Figure 10"captionStartId="F11189747"captionText="Figure 10. Mexicope maletensis sp. nov. male holotype (SMF 62000), confocal laser scanning microscopy (cLSM) images of pleopods: A pleotelson in ventral view; B pleopod I; C pleopod II; D pleopod III and IV. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure10"httpUri="https://binary.pensoft.net/fig/985854">10</figureCitation>
A and B) length 2.1 width, proximally widest, with shallow lateral notch distally of proximal third, progressively narrower from notch to apex; distolateral lobes narrow, pointed and pointing caudolaterally, laterally with 3–4 long, simple setae; distomedial lobes slightly shorter and wider, apex broadly rounded, distal margin with 4 simple setae.
<figureCitationid="C793AEAA0F9CE48CA2765854FD68EC66"captionStart="Figure 9"captionStartId="F11189745"captionText="Figure 9. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings pleopods: A pleotelson in ventral view, uropodal setae omitted; B pleopod I; C pleopods III and IV (underneath); D pleopod II. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure9"httpUri="https://binary.pensoft.net/fig/985848">9</figureCitation>
C and Fig.
<figureCitationid="5A740CCB66B2AEED935DDA3238A3C7A3"captionStart="Figure 10"captionStartId="F11189747"captionText="Figure 10. Mexicope maletensis sp. nov. male holotype (SMF 62000), confocal laser scanning microscopy (cLSM) images of pleopods: A pleotelson in ventral view; B pleopod I; C pleopod II; D pleopod III and IV. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure10"httpUri="https://binary.pensoft.net/fig/985854">10</figureCitation>
C) length 1.7 width, basis lateral margin mid- 1 / 3 convex, apex narrowly rounded. Lateral margin with row of simple setae, distolateral with row of pappose setae, apex with 2 long, simple setae. Exopod asetose, length approx. 2 width, articulating at approx. 2 / 3 of the length of the basipodite. Endopod inserting at mid-length of basis, stylet longer than body length, distal end whip-like, coiled at least 10 times.
<figureCitationid="01C3A8E1AC323A3ABEC725983F41315B"captionStart="Figure 9"captionStartId="F11189745"captionText="Figure 9. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings pleopods: A pleotelson in ventral view, uropodal setae omitted; B pleopod I; C pleopods III and IV (underneath); D pleopod II. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure9"httpUri="https://binary.pensoft.net/fig/985848">9</figureCitation>
D and Fig.
<figureCitationid="1ADAA990D6143754729983F0FF770C25"captionStart="Figure 10"captionStartId="F11189747"captionText="Figure 10. Mexicope maletensis sp. nov. male holotype (SMF 62000), confocal laser scanning microscopy (cLSM) images of pleopods: A pleotelson in ventral view; B pleopod I; C pleopod II; D pleopod III and IV. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure10"httpUri="https://binary.pensoft.net/fig/985854">10</figureCitation>
D) exopod longer than endopod, distal end wide, rounded, lateral and distomesial margin densely setose, apex with 6 plumose setae; endopod distally with 7 plumose setae.
<figureCitationid="50F7BB47FC73412DA6AEE8DDF66DF7D4"captionStart="Figure 9"captionStartId="F11189745"captionText="Figure 9. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings pleopods: A pleotelson in ventral view, uropodal setae omitted; B pleopod I; C pleopods III and IV (underneath); D pleopod II. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure9"httpUri="https://binary.pensoft.net/fig/985848">9</figureCitation>
D) exopod length and width about 0.5 endopod length and width respectively, asetose.
<figureCitationid="274A322AF216CA9763913357527B6362"captionStart="Figure 2"captionStartId="F11189731"captionText="Figure 2. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings of habitus: A habitus lateral; B habitus dorsal; Scale bar = 1 mm."figureDoi="10.3897/BDJ.12.e121508.figure2"httpUri="https://binary.pensoft.net/fig/985841">2</figureCitation>
,
<figureCitationid="C70BA6FAC7497C61B3A92E38D5AB77E1"captionStart="Figure 9"captionStartId="F11189745"captionText="Figure 9. Mexicope maletensis sp. nov. male holotype (SMF 62000), digitised pencil drawings pleopods: A pleotelson in ventral view, uropodal setae omitted; B pleopod I; C pleopods III and IV (underneath); D pleopod II. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure9"httpUri="https://binary.pensoft.net/fig/985848">9</figureCitation>
,
<figureCitationid="3B3884DA8DB2D60C5228906025E660FD"captionStart="Figure 10"captionStartId="F11189747"captionText="Figure 10. Mexicope maletensis sp. nov. male holotype (SMF 62000), confocal laser scanning microscopy (cLSM) images of pleopods: A pleotelson in ventral view; B pleopod I; C pleopod II; D pleopod III and IV. Scale bar = 250 µm."figureDoi="10.3897/BDJ.12.e121508.figure10"httpUri="https://binary.pensoft.net/fig/985854">10</figureCitation>
) 0.33 body length, 0.96 Plt length, protopod and rami cylindrical, protopod length 8.3 width, with 6–10 simple setae scattered across article and 3 robust setae on mesial margin; endopod length 1.1 protopod length, caudally pointing parallel to longitudinal body axis, with 8–9 simple setae; endopod length 1.9 exopod length, pointing caudolaterally at an angle of ca. 45 degrees from longitudinal axis, distally with 4–5 simple setae.
were based on male specimens, because only a single male specimen of
<taxonomicNameid="BCD894D4A4DDBE4FA9B0C130A43B078B"authority="Riehl & Schienbein & Mifsud, 2024"authorityName="Riehl & Schienbein & Mifsud"authorityYear="2024"class="Malacostraca"family="Acanthaspidiidae"genus="Mexicope"kingdom="Animalia"order="Isopoda"phylum="Arthropoda"rank="species"species="maletensis"status="sp. nov.">
was available for this study. While similarities to some congeners are evident in various characters,
<taxonomicNameid="4FEA7DA5673B8E5BB3D72E9384E01A60"authority="Riehl & Schienbein & Mifsud, 2024"authorityName="Riehl & Schienbein & Mifsud"authorityYear="2024"class="Malacostraca"family="Acanthaspidiidae"genus="Mexicope"kingdom="Animalia"order="Isopoda"phylum="Arthropoda"rank="species"species="maletensis"status="sp. nov.">
is based on typical family characters, such as the pointed body outline, single lateral projections on pereonites 1 and 5–7, bifid lateral projections on pereonites 3–4, antenna with a long flagellum and article 3 with exopod and cylindrical uropods (
<bibRefCitationid="F15F61F12448444A3DBFF2F0D8134EB1"author="Wagele"firstAuthor="Wagele"journalOrPublisher="E. Schweizerbart'sche Verlagsbuchhandlung Stuttgart"refId="B11189376"refString="Wägele Johann-Wolfgang 1989 Evolution und phylogenetisches System der Isopoda: Stand der Forschung und neue Erkenntnisse Evolution and phylogeny of isopods. New data and the state of affairs E. Schweizerbart'sche Verlagsbuchhandlung Stuttgart 978-3 - 510 - 55026 - 5"title="Evolution und phylogenetisches System der Isopoda: Stand der Forschung und neue Erkenntnisse"year="1989">Wägele 1989</bibRefCitation>
,
<bibRefCitationid="B8636DDF242D329A9E9351A224FC577A"author="Brandt"firstAuthor="Brandt"issue="3"journalOrPublisher="Zoological Journal of the Linnean Society"pagination="203252"refId="B11189384"refString="Brandt Angelika 1991 A revision of the Acanthaspidiidae Menzies, 1962 (Isopoda: Asellota) Zoological Journal of the Linnean Society 102 3 203 252 10.1111/j.1096-3642.1991.tb00001.x"title="A revision of the Acanthaspidiidae Menzies, 1962 (Isopoda: Asellota)"volume="102"year="1991">Brandt 1991</bibRefCitation>
,
<bibRefCitationid="7D8445FEDD8872061B5B5F93A7245F87"author="Just"firstAuthor="Just"issue="6"journalOrPublisher="Invertebrate Systematics"pagination="909925"refId="B11189393"refString="Just Jean 2001 New species of Mexicope, stat. nov. and Ianthopsis from Australia and a rediagnosis of Acanthaspidiidae (Isopoda: Asellota) Invertebrate Systematics 15 6 909 925 10.1071/IT00037"title="New species of Mexicope, stat. nov. and Ianthopsis from Australia and a rediagnosis of Acanthaspidiidae (Isopoda: Asellota)"volume="15"year="2001">Just 2001</bibRefCitation>
<taxonomicNameid="1FECBAD98A50C92546FFCAF1C4168F62"authority="Riehl & Schienbein & Mifsud, 2024"authorityName="Riehl & Schienbein & Mifsud"authorityYear="2024"class="Malacostraca"family="Acanthaspidiidae"genus="Mexicope"kingdom="Animalia"order="Isopoda"phylum="Arthropoda"rank="species"species="maletensis"status="sp. nov.">
peduncle article 6 slightly longer than 5; left Md with 6 denticulate spine-like setae, molar strongly tapering; PlpI proximal 1 / 3 broadest, abruptly narrowing, slightly tapering towards apex; PlpII basis lateral margin mid- 1 / 3 broadly convex with fringe of long slender setae, distal 1 / 3 concavely tapering to blunt point, endopod stylet long, whip-like, coiled extension; PlpIII exopod distal margin with 6 plumose setae; PlpIV exopod about half length of endopod, slender, naked; uropods about as long as Plt.
</paragraph>
<paragraphid="5BBD6F2CE25FA90C06BB2DF7AF809A60">
<taxonomicNameid="4DBD8CE8942C77990859F9B1D27EBA5F"authority="Riehl & Schienbein & Mifsud, 2024"authorityName="Riehl & Schienbein & Mifsud"authorityYear="2024"class="Malacostraca"family="Acanthaspidiidae"genus="Mexicope"kingdom="Animalia"order="Isopoda"phylum="Arthropoda"rank="species"species="maletensis"status="sp. nov.">
flagellum article 1 conjoint, length as long as remaining 13 short articles (half-length of 14 short articles), Md palp absent (present), right Md with 6 denticulate spine-like setae, length progressively increasing, distal to proximal denticles number increasing (with 8 such setae),
<taxonomicNameid="BFABCD89FA36D842211A77B73CD8D614"authority="Riehl & Schienbein & Mifsud, 2024"authorityName="Riehl & Schienbein & Mifsud"authorityYear="2024"class="Malacostraca"family="Acanthaspidiidae"genus="Mexicope"kingdom="Animalia"order="Isopoda"phylum="Arthropoda"rank="species"species="maletensis"status="sp. nov.">
lateral and middle lobes each with 2 long and 2 short strongly serrate setae; Mxp epipodite linguiform; pereopods similar in shape, setation subequal, PI – III proportionally shorter than PIV – VII, length differences mostly caused by length variation of propodus; PlpI proximally widest, lateral margin narrowing abruptly, tapering smoothly to bilobed apex; PlpII lateral margin medially strongly convex, with dense row of simple setae, distolateral margin concave, endopod stylet long, distally coiled; PlpIII exopod distal margin with 6 plumose setae, exopod lateral margin with continuous fringe of setae; PlpIV exopod half as long as endopod, apically acute.
</paragraph>
<paragraphid="E04E60622F9C634EF7EAFDCA79A4506C">
<taxonomicNameid="7A60050E094D9BBA709168AE795336F5"authority="Riehl & Schienbein & Mifsud, 2024"authorityName="Riehl & Schienbein & Mifsud"authorityYear="2024"class="Malacostraca"family="Acanthaspidiidae"genus="Mexicope"kingdom="Animalia"order="Isopoda"phylum="Arthropoda"rank="species"species="maletensis"status="sp. nov.">
heavily setose, flagellum with 13 articles, first article longest; Md palp absent, molar process conical setiferous, left lacinia quadridentate, one distal simple spine;
inner ramus shorter than outer one; Mxp palp 5 - segmented, segment width subequal, distal segment setose, endite broad, outer margin rounded, inner margin 2 coupling hooks, distal third with numerous setules, epipodite short, apically narrowly rounded; P propodus longest segment, merus bulbous, dactylus with two claws; PVII longest; PlpI laterally setose; PlpII protopod outer margin with long and short setae, endopod exceeding length of protopod, distally coiled; Urp elongate, biramous, peduncle length similar exopod length.
</paragraph>
<paragraphid="20CAD3C0D0C1568CCFEDEBB72EE5DA8A">
<taxonomicNameid="F9F61DBA315F8E8DE6DEBD87598DD946"authority="Riehl & Schienbein & Mifsud, 2024"authorityName="Riehl & Schienbein & Mifsud"authorityYear="2024"class="Malacostraca"family="Acanthaspidiidae"genus="Mexicope"kingdom="Animalia"order="Isopoda"phylum="Arthropoda"rank="species"species="maletensis"status="sp. nov.">
as follows: body length almost 2.0 width (length almost 3.0 width), eyes ventrolaterally (dorsolaterally), Prn 1 widest (Prn 3 and 4 widest); left Md distally with 5 dentate spines (with 6 spines); PlpII endopod distally coiled at least 10 times (stylet coiled once).
The initial difficulties we had in assigning the new species to a genus are emblematic of the currently inadequate and vague diagnoses of all three genera of
<bibRefCitationid="917F11D33133BE8D71D609BB3C4A811A"author="Timm Marlene & Kaiser Stefanie & Brandt Angelika"etAl="et al."firstAuthor="Timm"issue="1"journalOrPublisher="Zootaxa"pagination="238258"refId="B11189444"refString="Timm Marlene, Kaiser Stefanie, Brandt Angelika 2013 A new species of Acanthaspidia Stebbing, 1898 (Isopoda, Asellota, Acanthaspidiidae) from the bathyal Weddell Sea (Southern Ocean) Zootaxa 3692 1 238 258 http://biotaxa.org.ololo.sci-hub.bz/Zootaxa/article/view/zootaxa.3692.1.12 10.11646/zootaxa.3692.1.12"title="A new species of Acanthaspidia Stebbing, 1898 (Isopoda, Asellota, Acanthaspidiidae) from the bathyal Weddell Sea (Southern Ocean)"volume="3692"year="2013">Timm et al. (2013)</bibRefCitation>
). With previously only three known species for the genus
, it is no surprise that, for each new species, a modification of the generic diagnoses was necessary and the discrimination amongst the acanthaspidiid genera was partially blurry. This development is particularly evident in
<bibRefCitationid="35CD1120A771B38C3EDB4E0E8932B580"author="Just"firstAuthor="Just"issue="6"journalOrPublisher="Invertebrate Systematics"pagination="909925"refId="B11189393"refString="Just Jean 2001 New species of Mexicope, stat. nov. and Ianthopsis from Australia and a rediagnosis of Acanthaspidiidae (Isopoda: Asellota) Invertebrate Systematics 15 6 909 925 10.1071/IT00037"title="New species of Mexicope, stat. nov. and Ianthopsis from Australia and a rediagnosis of Acanthaspidiidae (Isopoda: Asellota)"volume="15"year="2001">Just 2001</bibRefCitation>
,
<bibRefCitationid="62D6419E9D61DBF4EB0D115ABAFE0EFF"author="Bruce"firstAuthor="Bruce"journalOrPublisher="Zootaxa"pagination="111"refId="B11189402"refString="Bruce N. L. 2004 Mexicope sushara sp. nov., the first New Zealand record of the isopod crustacean family Acanthaspidiidae (Asellota) Zootaxa 489 1 11 http://decapoda.nhm.org/pdfs/9978/9978.pdf10.11646/zootaxa.489.1.1"title="Mexicope sushara sp. nov., the first New Zealand record of the isopod crustacean family Acanthaspidiidae (Asellota)"volume="489"year="2004">Bruce 2004</bibRefCitation>
in some character states leading to difficulties to differentiate between these genera and to classify the new species described here. Character states that support the classification of the new species as either
are the absence of dorsal tubercles on the cephalothorax, the presence of eyes on eyestalks, single lateral projections on pereonite 1, the absence of tergal spines or humps, a fringe of long setae laterally on the second pleopod basis which are longest apically, finely serrated pleotelson margins and uropod rami that are at least as long as the peduncle. The presence of a simple, bulge-shaped rostrum, the antennula length of 0.25 times antenna length, the absence of a triangular lobe on antenna article 6 and the short, curved, robust setae on the pleotelson on the one hand speak for a classification of the new species as
, on the other hand, is supported by the presence of a pre-ocular spine, rows of elongate, simple setae on the posterolateral projections of pereonites 2–4 and 6–7, the presence of a sternal spine on pereonite 7, prognathous mouthparts, a strongly tapering, pointed mandibular molar with long apical setae, the lack of a mandibular palp, a short maxilliped epipod reaching only half way between the coxo-basal articulation and the palp articulation, a coiled pleopod II stylet and uropods that are as long as the pleotelson. In summary, over ten, partially complex characters suggest the classification as
<tableCitationid="B3A17EC8AE99C95AF5D984BA9D8B6D04"captionStart="Table 1"captionStartId="T11189718"captionText="Table 1. Comparison of diagnostic characters of Ianthopsis (Just 2001) and Mexicope (Just 2001, Bruce 2004) with those of the new species Mexicope maletensis sp. nov. Similarities / overlaps are highlighted in grey, entirely identical character states mentioned in the aforementioned diagnoses were omitted."httpUri="http://table.plazi.org/id/B49F0F3B3AA18B48B4B64590D1CDAA5A"tableUuid="B49F0F3B3AA18B48B4B64590D1CDAA5A">1</tableCitation>
