<documentid="BA134D6365D52F6F5F8B89F40F4F43B1"ID-DOI="10.3853/j.0067-1975.61.2009.1529"ID-ISSN="2201-4349"ID-Zenodo-Dep="5238755"IM.materialsCitations_approvedBy="felipe"IM.metadata_approvedBy="felipe"IM.tables_requiresApprovalFor="existingObjects,plazi"IM.taxonomicNames_approvedBy="felipe"checkinTime="1629572455428"checkinUser="felipe"docAuthor="Capa, María & Murray, Anna"docDate="2009"docId="2202BF4FFFCF5B7BFC06548FFBBDFEB8"docLanguage="en"docName="RecAustMus.61.2.201.224.pdf"docOrigin="Records of the Australian Museum 61 (2)"docSource="http://dx.doi.org/10.3853/j.0067-1975.61.2009.1529"docStyle="DocumentStyle:7863F7301B7BEE922F541F6F9B5AEEC6.2:RecAustMus.2008-2018.journal_article.0cover"docStyleId="7863F7301B7BEE922F541F6F9B5AEEC6"docStyleName="RecAustMus.2008-2018.journal_article.0cover"docStyleVersion="2"docTitle="Megalomma Johansson 1925"docType="treatment"docVersion="4"lastPageNumber="205"masterDocId="DE3BC737FFCC5B7FFF9D5167FF8AFFD9"masterDocTitle="Review of the Genus Megalomma (Polychaeta: Sabellidae) in Australia with Description of Three New Species, New Records and Notes on Certain Features with Phylogenetic Implications"masterLastPageNumber="224"masterPageNumber="201"pageNumber="204"updateTime="1719342478377"updateUser="felipe"zenodo-license-document="CC-BY-4.0"zenodo-license-figures="CC-BY-4.0">
<mods:titleid="CC271152C9FE2789B631D520749EA647">Review of the Genus Megalomma (Polychaeta: Sabellidae) in Australia with Description of Three New Species, New Records and Notes on Certain Features with Phylogenetic Implications</mods:title>
<bibRefCitationid="CE3A73A8FFCF5B7CFBA0548FFA86F9DB"author="Johansson, K"box="[1085,1292,1512,1538]"pageId="3"pageNumber="204"pagination="1 - 28"refId="ref18327"refString="Johansson, K. E., 1925. Bemerkungen uber die Kinberg'schen Arten der Familien Hermellidae und Sabellidae. Arkiv fur Zoologie 18: 1 - 28."type="journal article"year="1925">Johansson, 1925</bibRefCitation>
<bibRefCitationid="CE3A73A8FFCF5B7CFB77575BFA07F98A"author="Montagu, G"box="[1258,1421,1596,1619]"pageId="3"pageNumber="204"pagination="18 - 21"refId="ref18455"refString="Montagu, G., 1815. Descriptions of several new or rare animals principally marine found on the south coast of Devonshire. Transactions of the Linnean Society of London 11: 18 - 21."type="journal article"year="1815">Montagu, 1815</bibRefCitation>
</taxonomicName>
(see Tovar-Hernández & Salazar-Vallejo, 2008).
. Presence of subdistal, sessile and compound radiolar eyes, at least on the internal margin of the dorsalmost pair of radioles (
<bibRefCitationid="CE3A73A8FFCF5B7CFBF157AFFA99F906"author="Fitzhugh, K"box="[1132,1299,1736,1759]"pageId="3"pageNumber="204"pagination="1 - 104"refId="ref17898"refString="Fitzhugh, K., 1989. A Systematic revision of the Sabellidae - Caobangiidae - Sabellongidae complex (Annelida: Polychaeta). Bulletin of the American Museum of Natural History 192: 1 - 104."type="journal article"year="1989">Fitzhugh, 1989</bibRefCitation>
. There are other morphological characters that have been included in the diagnosis of the genus (see last emendation by Tovar-Hernández & Salazar-Vallejo, 2008) and are herein assessed.
has been attributed with rounded external margins of radioles, but some of the species described in the present study clearly show distinct externally quadrangular margins along some length of their radioles (
<figureCitationid="329012DCFFC85B7BFD2C51FDFC86FF68"box="[689,780,154,177]"captionStart="Figure 1"captionStartId="1.[121,184,1794,1815]"captionText="Figure 1 (facing). SEM. (A–D) Types of collar dorsal margins: (A) separated and with no pockets as in Megalomma sp. 2; (B) fused to the faecal groove and forming vestigial pockets on each side, as in Megalomma interrupta n.sp.; (C) fused to the faecal grove and with short dorsal lappets as in M. phyllisae n.sp.; (D) fused to the faecal groove and with spatulate dorsal lappets as in M. cf. acrophthalmos. (E,F) Types of inferior thoracic chaetae: (E) Megalomma phyllisae n.sp. with broadly hooded chaetae type A and (F) M. cf. acrophthalmos with broadly hooded chaetae type B. (G,H) Shape of radioles: (G) M. cf. acrophthalmos with quadrangular external margins at the base; (H) M. inflata n.sp. with quadrangular distal margins of radioles. (I,J) Parallel lamellae and ventral sacs, smaller in (I) Megalomma cf. miyukiae and, more developed in (J) M. interrupta n.sp. (K,L) Abdominal chaetae: (K) narrowly hooded and (L) broadly hooded. (M) Companion chaetae of M. cf. miyukiae showing the asymmetrical and dentate membrane."pageId="4"pageNumber="205">Fig. 1G</figureCitation>
). However, it is not easy to distinguish between the two states (see also
<bibRefCitationid="CE3A73A8FFC85B7BFED151B2FE7BFF35"author="Fitzhugh, K"box="[332,497,213,236]"pageId="4"pageNumber="205"pagination="1 - 104"refId="ref17898"refString="Fitzhugh, K., 1989. A Systematic revision of the Sabellidae - Caobangiidae - Sabellongidae complex (Annelida: Polychaeta). Bulletin of the American Museum of Natural History 192: 1 - 104."type="journal article"year="1989">Fitzhugh, 1989</bibRefCitation>
, p. 21), and this may not be a significant character anyway. The species studied have longitudinal bands of cilia on the outer lateral edges (
<figureCitationid="329012DCFFC85B7BFD735068FF4DFE9D"captionStart="Figure 1"captionStartId="1.[121,184,1794,1815]"captionText="Figure 1 (facing). SEM. (A–D) Types of collar dorsal margins: (A) separated and with no pockets as in Megalomma sp. 2; (B) fused to the faecal groove and forming vestigial pockets on each side, as in Megalomma interrupta n.sp.; (C) fused to the faecal grove and with short dorsal lappets as in M. phyllisae n.sp.; (D) fused to the faecal groove and with spatulate dorsal lappets as in M. cf. acrophthalmos. (E,F) Types of inferior thoracic chaetae: (E) Megalomma phyllisae n.sp. with broadly hooded chaetae type A and (F) M. cf. acrophthalmos with broadly hooded chaetae type B. (G,H) Shape of radioles: (G) M. cf. acrophthalmos with quadrangular external margins at the base; (H) M. inflata n.sp. with quadrangular distal margins of radioles. (I,J) Parallel lamellae and ventral sacs, smaller in (I) Megalomma cf. miyukiae and, more developed in (J) M. interrupta n.sp. (K,L) Abdominal chaetae: (K) narrowly hooded and (L) broadly hooded. (M) Companion chaetae of M. cf. miyukiae showing the asymmetrical and dentate membrane."pageId="4"pageNumber="205">Fig. 1H</figureCitation>
) as stated by
<bibRefCitationid="CE3A73A8FFC85B7BFECD504AFE60FE9D"author="Perkins, T"box="[336,490,301,324]"pageId="4"pageNumber="205"pagination="285 - 368"refId="ref18715"refString="Perkins, T. H., 1984. Revision of Demonax Kinberg, Hypsicomus Grube, and Notaulax Tauber, with a review of Megalomma Johansson from Florida (Polychaeta: Sabellidae). Proceedings of the Biological Society of Washington 97: 285 - 368."type="journal article"year="1984">Perkins (1984)</bibRefCitation>
The radioles are supported by rows of vacuolated cells (referred to as the radiolar skeleton). The number of rows is variable within the genus and also within some of the species. It has been stated by Tovar-Hernández & Salazar-Vallejo (2008) that the maximum number of rows is 16, but some of the specimens described in this study (e.g.,
<taxonomicNameid="6DAB75DAFFC85B7BFD0B537FFC93FDF6"authority="Capa & Murray, 2009"authorityName="Capa & Murray"authorityYear="2009"box="[662,793,536,559]"class="Insecta"family="Carabidae"genus="Megalomma"kingdom="Animalia"order="Coleoptera"pageId="4"pageNumber="205"phylum="Arthropoda"rank="species"species="phyllisae"status="sp. nov.">
<figureCitationid="329012DCFFC85B7BFF7E5352FEB9FD95"box="[227,307,565,588]"captionStart="Figure 4"captionStartId="8.[374,437,892,913]"captionTargetBox="[382,1254,157,840]"captionTargetId="figure-9@8.[374,1258,151,852]"captionTargetPageId="8"captionText="Figure 4. Drawings to scale of thoracic and abdominal uncini. Megalomma phyllisae n.sp.:"figureDoi="http://doi.org/10.5281/zenodo.5238761"httpUri="https://zenodo.org/record/5238761/files/figure.png"pageId="4"pageNumber="205">Fig. 4A</figureCitation>
) exhibit up to 30 cells in transverse section (see variability of rows in radiolar skeleton in
<figureCitationid="329012DCFFC85B7BFDFD5335FD2AFDB0"box="[608,672,594,617]"captionStart="Figure 5"captionStartId="10.[416,481,1123,1144]"captionTargetBox="[420,1214,157,1082]"captionTargetId="figure-9@10.[416,1218,151,1088]"captionTargetPageId="10"captionText="Figure 5. Drawings to scale of radioles sections, at the base: (A) Megalomma"figureDoi="http://doi.org/10.5281/zenodo.5238765"httpUri="https://zenodo.org/record/5238765/files/figure.png"pageId="4"pageNumber="205">Fig. 5</figureCitation>
, the ventral lips terminate ventrally in parallel lamellae, as defined by
<bibRefCitationid="CE3A73A8FFC85B7BFE6153EAFD0CFD7D"author="Nicol, E"box="[508,646,653,676]"pageId="4"pageNumber="205"pagination="537 - 598"refId="ref18582"refString="Nicol, E. A. T., 1931. The feeding mechanism, formation of the tube, and physiology of digestion in Sabella pavonina. Transaction of the Royal Society of Edinburgh 56: 537 - 598."type="journal article"year="1931">Nicol (1931)</bibRefCitation>
and
<bibRefCitationid="CE3A73A8FFC85B7BFD2653EAFF7AFD18"author="Fitzhugh, K"pageId="4"pageNumber="205"pagination="1 - 104"refId="ref17898"refString="Fitzhugh, K., 1989. A Systematic revision of the Sabellidae - Caobangiidae - Sabellongidae complex (Annelida: Polychaeta). Bulletin of the American Museum of Natural History 192: 1 - 104."type="journal article"year="1989">Fitzhugh (1989)</bibRefCitation>
, seen between the ventral lappets of the peristomial collar, and some species also possess vesicles “formed by the outpocketing of the parallel lamellae” called ventral sacs (as in
<bibRefCitationid="CE3A73A8FFC85B7BFF7A5265FE01FCC0"author="Fitzhugh, K"box="[231,395,770,793]"pageId="4"pageNumber="205"pagination="1 - 104"refId="ref17898"refString="Fitzhugh, K., 1989. A Systematic revision of the Sabellidae - Caobangiidae - Sabellongidae complex (Annelida: Polychaeta). Bulletin of the American Museum of Natural History 192: 1 - 104."type="journal article"year="1989">Fitzhugh, 1989</bibRefCitation>
) (
<figureCitationid="329012DCFFC85B7BFE3D5265FE71FCC0"box="[416,507,770,793]"captionStart="Figure 1"captionStartId="1.[121,184,1794,1815]"captionText="Figure 1 (facing). SEM. (A–D) Types of collar dorsal margins: (A) separated and with no pockets as in Megalomma sp. 2; (B) fused to the faecal groove and forming vestigial pockets on each side, as in Megalomma interrupta n.sp.; (C) fused to the faecal grove and with short dorsal lappets as in M. phyllisae n.sp.; (D) fused to the faecal groove and with spatulate dorsal lappets as in M. cf. acrophthalmos. (E,F) Types of inferior thoracic chaetae: (E) Megalomma phyllisae n.sp. with broadly hooded chaetae type A and (F) M. cf. acrophthalmos with broadly hooded chaetae type B. (G,H) Shape of radioles: (G) M. cf. acrophthalmos with quadrangular external margins at the base; (H) M. inflata n.sp. with quadrangular distal margins of radioles. (I,J) Parallel lamellae and ventral sacs, smaller in (I) Megalomma cf. miyukiae and, more developed in (J) M. interrupta n.sp. (K,L) Abdominal chaetae: (K) narrowly hooded and (L) broadly hooded. (M) Companion chaetae of M. cf. miyukiae showing the asymmetrical and dentate membrane."pageId="4"pageNumber="205">Fig. 1I,J</figureCitation>
, as an erect, triangular ciliated lobe, between the dorsal lips. The examination of Australian specimens has determined the presence of a smooth “keel” in some species but its detailed morphology, ultrastructure or function has not been studied. It does not appear to be homologous to the caruncle, rather it is a smooth projection of the peristomium arising between the dorsal lips, forming a ventrally-directed ridge.
Characters and states relating to chaetae and uncini should also be reconsidered, as there is probably more variation in the genus than has been recorded so far. Previous studies agree that notochaetae of the first chaetiger are elongate and narrowly hooded, as are the rest of the superior thoracic chaetae (
<bibRefCitationid="CE3A73A8FFC85B7BFE9355B0FE3EFB37"author="Perkins, T"box="[270,436,1239,1262]"pageId="4"pageNumber="205"pagination="285 - 368"refId="ref18715"refString="Perkins, T. H., 1984. Revision of Demonax Kinberg, Hypsicomus Grube, and Notaulax Tauber, with a review of Megalomma Johansson from Florida (Polychaeta: Sabellidae). Proceedings of the Biological Society of Washington 97: 285 - 368."type="journal article"year="1984">Perkins, 1984</bibRefCitation>
;
<bibRefCitationid="CE3A73A8FFC85B7BFE5955B0FDFDFB37"author="Fitzhugh, K"box="[452,631,1239,1262]"pageId="4"pageNumber="205"pagination="1 - 104"refId="ref17898"refString="Fitzhugh, K., 1989. A Systematic revision of the Sabellidae - Caobangiidae - Sabellongidae complex (Annelida: Polychaeta). Bulletin of the American Museum of Natural History 192: 1 - 104."type="journal article"year="1989">Fitzhugh, 1989</bibRefCitation>
,
<bibRefCitationid="CE3A73A8FFC85B7BFD1B55B0FD48FB37"author="Fitzhugh, K"box="[646,706,1239,1262]"pageId="4"pageNumber="205"pagination="106 - 134"refId="ref17970"refString="Fitzhugh, K., 2003. A new species of Megalomma Johansson, 1927 (Polychaeta: Sabellidae: Sabellinae) from Taiwan, with comments on sabellid dorsal lip classification. Zoological Studies 42: 106 - 134"type="journal article"year="2003">2003</bibRefCitation>
; Tovar- Hernández & Salazar-Vallejo, 2008), and that the inferior thoracic notochaetae are broadly hooded (
<bibRefCitationid="CE3A73A8FFC85B7BFDE75475FC9CFAF0"author="Perkins, T"box="[634,790,1298,1321]"pageId="4"pageNumber="205"pagination="285 - 368"refId="ref18715"refString="Perkins, T. H., 1984. Revision of Demonax Kinberg, Hypsicomus Grube, and Notaulax Tauber, with a review of Megalomma Johansson from Florida (Polychaeta: Sabellidae). Proceedings of the Biological Society of Washington 97: 285 - 368."type="journal article"year="1984">Perkins, 1984</bibRefCitation>
;
<bibRefCitationid="CE3A73A8FFC85B7BFF3B5448FEC0FA9F"author="Fitzhugh, K"box="[166,330,1327,1350]"pageId="4"pageNumber="205"pagination="1 - 104"refId="ref17898"refString="Fitzhugh, K., 1989. A Systematic revision of the Sabellidae - Caobangiidae - Sabellongidae complex (Annelida: Polychaeta). Bulletin of the American Museum of Natural History 192: 1 - 104."type="journal article"year="1989">Fitzhugh, 1989</bibRefCitation>
,
<bibRefCitationid="CE3A73A8FFC85B7BFEC95448FE07FA9F"author="Fitzhugh, K"box="[340,397,1327,1350]"pageId="4"pageNumber="205"pagination="106 - 134"refId="ref17970"refString="Fitzhugh, K., 2003. A new species of Megalomma Johansson, 1927 (Polychaeta: Sabellidae: Sabellinae) from Taiwan, with comments on sabellid dorsal lip classification. Zoological Studies 42: 106 - 134"type="journal article"year="2003">2003</bibRefCitation>
; Tovar-Hernández & Salazar-Vallejo, 2008) but with hoods variable in length (Tovar-Hernández & Salazar-Vallejo, 2008). Abdominal neurochaetae have been described as elongated, narrowly hooded chaetae (
<bibRefCitationid="CE3A73A8FFC85B7BFD5C54E0FF55FA65"author="Perkins, T"pageId="4"pageNumber="205"pagination="285 - 368"refId="ref18715"refString="Perkins, T. H., 1984. Revision of Demonax Kinberg, Hypsicomus Grube, and Notaulax Tauber, with a review of Megalomma Johansson from Florida (Polychaeta: Sabellidae). Proceedings of the Biological Society of Washington 97: 285 - 368."type="journal article"year="1984">Perkins, 1984</bibRefCitation>
;
<bibRefCitationid="CE3A73A8FFC85B7BFF7154C2FE18FA65"author="Fitzhugh, K"box="[236,402,1445,1468]"pageId="4"pageNumber="205"pagination="1 - 104"refId="ref17898"refString="Fitzhugh, K., 1989. A Systematic revision of the Sabellidae - Caobangiidae - Sabellongidae complex (Annelida: Polychaeta). Bulletin of the American Museum of Natural History 192: 1 - 104."type="journal article"year="1989">Fitzhugh, 1989</bibRefCitation>
,
<bibRefCitationid="CE3A73A8FFC85B7BFE0254C2FE52FA65"author="Fitzhugh, K"box="[415,472,1445,1468]"pageId="4"pageNumber="205"pagination="106 - 134"refId="ref17970"refString="Fitzhugh, K., 2003. A new species of Megalomma Johansson, 1927 (Polychaeta: Sabellidae: Sabellinae) from Taiwan, with comments on sabellid dorsal lip classification. Zoological Studies 42: 106 - 134"type="journal article"year="2003">2003</bibRefCitation>
; Tovar-Hernández & Salazar- Vallejo, 2008) (
<figureCitationid="329012DCFFC85B7BFECF54A5FE22FA00"box="[338,424,1474,1497]"captionStart="Figure 1"captionStartId="1.[121,184,1794,1815]"captionText="Figure 1 (facing). SEM. (A–D) Types of collar dorsal margins: (A) separated and with no pockets as in Megalomma sp. 2; (B) fused to the faecal groove and forming vestigial pockets on each side, as in Megalomma interrupta n.sp.; (C) fused to the faecal grove and with short dorsal lappets as in M. phyllisae n.sp.; (D) fused to the faecal groove and with spatulate dorsal lappets as in M. cf. acrophthalmos. (E,F) Types of inferior thoracic chaetae: (E) Megalomma phyllisae n.sp. with broadly hooded chaetae type A and (F) M. cf. acrophthalmos with broadly hooded chaetae type B. (G,H) Shape of radioles: (G) M. cf. acrophthalmos with quadrangular external margins at the base; (H) M. inflata n.sp. with quadrangular distal margins of radioles. (I,J) Parallel lamellae and ventral sacs, smaller in (I) Megalomma cf. miyukiae and, more developed in (J) M. interrupta n.sp. (K,L) Abdominal chaetae: (K) narrowly hooded and (L) broadly hooded. (M) Companion chaetae of M. cf. miyukiae showing the asymmetrical and dentate membrane."pageId="4"pageNumber="205">Fig. 1K</figureCitation>
) but they could be interpreted as broadly hooded (but with long tips) in some species (
<figureCitationid="329012DCFFC85B7BFD7354B8FF4CF9CD"captionStart="Figure 1"captionStartId="1.[121,184,1794,1815]"captionText="Figure 1 (facing). SEM. (A–D) Types of collar dorsal margins: (A) separated and with no pockets as in Megalomma sp. 2; (B) fused to the faecal groove and forming vestigial pockets on each side, as in Megalomma interrupta n.sp.; (C) fused to the faecal grove and with short dorsal lappets as in M. phyllisae n.sp.; (D) fused to the faecal groove and with spatulate dorsal lappets as in M. cf. acrophthalmos. (E,F) Types of inferior thoracic chaetae: (E) Megalomma phyllisae n.sp. with broadly hooded chaetae type A and (F) M. cf. acrophthalmos with broadly hooded chaetae type B. (G,H) Shape of radioles: (G) M. cf. acrophthalmos with quadrangular external margins at the base; (H) M. inflata n.sp. with quadrangular distal margins of radioles. (I,J) Parallel lamellae and ventral sacs, smaller in (I) Megalomma cf. miyukiae and, more developed in (J) M. interrupta n.sp. (K,L) Abdominal chaetae: (K) narrowly hooded and (L) broadly hooded. (M) Companion chaetae of M. cf. miyukiae showing the asymmetrical and dentate membrane."pageId="4"pageNumber="205">Fig. 1L</figureCitation>
). The length of the thoracic uncini handle could also be considered as useful for discriminating between species as this varies from medium length (same length as the distance from main fang to breast) to long (twice the length of the distance from main fang to breast).
The thoracic companion chaetae possess a proximal shaft or handle, generally similar in length to the thoracic uncini handle, and a distal membrane that has been described as teardrop-shaped by most authors (
<bibRefCitationid="CE3A73A8FFC85B7BFD8F5780FD20F927"author="Perkins, T"box="[530,682,1767,1790]"pageId="4"pageNumber="205"pagination="285 - 368"refId="ref18715"refString="Perkins, T. H., 1984. Revision of Demonax Kinberg, Hypsicomus Grube, and Notaulax Tauber, with a review of Megalomma Johansson from Florida (Polychaeta: Sabellidae). Proceedings of the Biological Society of Washington 97: 285 - 368."type="journal article"year="1984">Perkins, 1984</bibRefCitation>
;
<bibRefCitationid="CE3A73A8FFC85B7BFD295780FF54F8C5"author="Fitzhugh, K"pageId="4"pageNumber="205"pagination="1 - 104"refId="ref17898"refString="Fitzhugh, K., 1989. A Systematic revision of the Sabellidae - Caobangiidae - Sabellongidae complex (Annelida: Polychaeta). Bulletin of the American Museum of Natural History 192: 1 - 104."type="journal article"year="1989">Fitzhugh, 1989</bibRefCitation>
,
<bibRefCitationid="CE3A73A8FFC85B7BFF715662FEAEF8C5"author="Fitzhugh, K"box="[236,292,1797,1820]"pageId="4"pageNumber="205"pagination="353 - 424"refId="ref17936"refString="Fitzhugh, K., 2002. Fan worm polychaetes (Sabellidae: Sabellinae) collected during the Thai-Danish Bioshelf Project. Phuket Marine Biological Center Special Publication 24: 353 - 424."type="journal article"year="2002">2002</bibRefCitation>
,
<bibRefCitationid="CE3A73A8FFC85B7BFEAF5662FEE1F8C5"author="Fitzhugh, K"box="[306,363,1797,1820]"pageId="4"pageNumber="205"pagination="106 - 134"refId="ref17970"refString="Fitzhugh, K., 2003. A new species of Megalomma Johansson, 1927 (Polychaeta: Sabellidae: Sabellinae) from Taiwan, with comments on sabellid dorsal lip classification. Zoological Studies 42: 106 - 134"type="journal article"year="2003">2003</bibRefCitation>
), or as roughly symmetrical (
<bibRefCitationid="CE3A73A8FFC85B7BFD2E5662FF57F8E0"author="Fitzhugh, K"pageId="4"pageNumber="205"pagination="1 - 104"refId="ref17898"refString="Fitzhugh, K., 1989. A Systematic revision of the Sabellidae - Caobangiidae - Sabellongidae complex (Annelida: Polychaeta). Bulletin of the American Museum of Natural History 192: 1 - 104."type="journal article"year="1989">Fitzhugh, 1989</bibRefCitation>
; Tovar-Hernández & Salazar-Vallejo, 2006;
<bibRefCitationid="CE3A73A8FFC85B7BFD3D5645FEA4F88F"author="Giangrande, A"pageId="4"pageNumber="205"pagination="41 - 53"refId="ref18129"refString="Giangrande, A., M. Licciano & M. C. Gambi, 2007. A collection of Sabellidae (polychaeta) from Carrie Bow Cay (Belize, western Caribbean Sea) with the description of two new species. Zootaxa 1650: 41 - 53."type="journal article"year="2007">
<bibRefCitationid="CE3A73A8FFC85B7BFDB05658FC84F88F"author="Knight-Jones, P"box="[557,782,1855,1878]"pageId="4"pageNumber="205"pagination="313 - 323"refId="ref18415"refString="Knight-Jones, P., 1997. Two new species of Megalomma (Sabellidae) from Sinai and New Zealand with redescriptions of some types and a new genus. Bulletin of Marine Science 60: 313 - 323."type="journal article"year="1997">Knight-Jones, 1997</bibRefCitation>
). After studying the position of the small rows of teeth and the orientation of the tip of the distal membrane, we have concluded that the membrane is asymmetrical (
<figureCitationid="329012DCFFC85B7BFD2D56F0FC87F877"box="[688,781,1943,1966]"captionStart="Figure 1"captionStartId="1.[121,184,1794,1815]"captionText="Figure 1 (facing). SEM. (A–D) Types of collar dorsal margins: (A) separated and with no pockets as in Megalomma sp. 2; (B) fused to the faecal groove and forming vestigial pockets on each side, as in Megalomma interrupta n.sp.; (C) fused to the faecal grove and with short dorsal lappets as in M. phyllisae n.sp.; (D) fused to the faecal groove and with spatulate dorsal lappets as in M. cf. acrophthalmos. (E,F) Types of inferior thoracic chaetae: (E) Megalomma phyllisae n.sp. with broadly hooded chaetae type A and (F) M. cf. acrophthalmos with broadly hooded chaetae type B. (G,H) Shape of radioles: (G) M. cf. acrophthalmos with quadrangular external margins at the base; (H) M. inflata n.sp. with quadrangular distal margins of radioles. (I,J) Parallel lamellae and ventral sacs, smaller in (I) Megalomma cf. miyukiae and, more developed in (J) M. interrupta n.sp. (K,L) Abdominal chaetae: (K) narrowly hooded and (L) broadly hooded. (M) Companion chaetae of M. cf. miyukiae showing the asymmetrical and dentate membrane."pageId="4"pageNumber="205">Fig. 1M</figureCitation>
). There is some variation in the form of the companion chaetae among different species, so this character may be useful from a systematic point of view.
Note: generic diagnostic characters have been omitted from species descriptions, In
<tableCitationid="E7293BE2FFC85B7BFBE05195FB46FED0"box="[1149,1228,242,265]"captionStart="Table 2"captionStartId="21.[121,179,169,192]"captionText="Table 2. Summary of groups proposed by Knight-Jones (1997) and subsequent authors, including combinations of characters not considered previously. Some taxa have been moved to different groups after examination of type material or reinterpretation of original descriptions and drawings. NSW: New South Wales, NT: Northern Territory, QLD: Queensland, VIC: Victoria, WA: Western Australia."pageId="4"pageNumber="205">Table 2</tableCitation>
, we have incorporated the new species into Knight-Jones’ operational “Groups”, and we have re-interpreted collar fusion, lappets and presence of pockets for some taxa.
