Gymnopleura Bourne, 1922

GUINOT, DANIÈLE, TAVARES, MARCOS & CASTRO, PETER, 2013, Significance of the sexual openings and supplementary structures on the phylogeny of brachyuran crabs (Crustacea, Decapoda, Brachyura), with new nomina for higher-ranked podotreme taxa, Zootaxa 3665 (1), pp. 1-414 : 304-305

Subsection Gymnopleura Bourne, 1922

Superfamilies included. Raninoidea De Haan, 1839 ; †Palaeocorystoidea Lôrenthey in Lôrenthey & Beurlen 1929 (see Tables 1, 5, 6).

Diagnosis. Thoracic sternum entirely filling width of sterno-abdominal depression. Anterior sternites usually crown-shaped, sternite 4 widened, shield-shaped ( Cyrtorhininae excepted), posterior sternites narrow, even linear. Sutures 4/5 crescent-shaped or slightly elongated; sutures 5/6–7/8 short. Paired spermatheca typically depending of endosternite 7/8 but apertures displaced anteriorly on sternite 7, approximately at level of P3 coxa, practically contiguous, deeply recessed ( Symethinae excepted). Sterno-coxal depressions absent. Pleurites 5–7 not exposed or partially exposed (gymnopleurity). Oxystome condition always present. Male abdomen short, with 6 free somites plus telson. Male pleopods absent on somites 3–5. Uropods transformed into sockets for abdominal holding ( Lyreididae ) or sockets absent (lost). Female Pl 1 absent. Male and immature female abdominal holding, if present ( Lyreididae ), consisting of a paired structure on sternite 5. P2–P4 variously modified, with distal articles (particularly propodi, dactyli) flattened, enlarged for burying, digging. P5 generally reduced, may be filiform, without subcheliform structure (carrying behaviour absent) but with variously modified distal articles. Male P5 coxa partially extended to enclose penis. G1 elongated, cylindrical, or stout, not entirely tubular; G2 without vestigial exopodite, elongated or spatuliform, often with short or long styliform ending. Axial skeleton with connections by fusion, strongly modified; sella turcica fused with interopleurite 6/7.

Remarks. The first rhizonym coined on the basis of a generic nomen ( Ranina Lamarck, 1801 ) referred to this subsection was Raniniens proposed by H. Milne Edwards (1837a: 167, 190) for a “tribe” accomodating three genera: Ranina and two new genera Ranilia H. Milne Edwards, 1837 , and Raninoides H. Milne Edwards, 1837 . The nomen Raniniens is in the same situation as the nomen Homoliens discussed above (with the difference that De Haan recognised Raninoidea as a valid taxon): it is a rhizonym that clearly belongs in the family-series, subsequently Latinised. It should therefore be considered available as given in the publication of H. Milne Edwards (1837a).

There are several aponyms of the nomen Raniniens, with different spellings and ranks. They include: family Raninoidea (De Haan 1839; 1849); family Raninidae ( White 1847: 56; Alcock 1895: 135, 136, 288; A. Milne- Edwards & Bouvier 1902: 7; Balss 1957: 1616); “tribe” Raninina ( Brandt 1851: 91); “subtribe” Raninidea ( Dana 1852: 54, 403); “group” Raninidea ( Henderson 1888: ix, 26; 1893: 408); “legion” Ranininea ( Stebbing 1893: 139); subfamily Raninoidinae (Lôrenthey in Lôrenthey & Beurlen 1929: 299); superfamily Raninoidea ( Guinot 1978a: 237, 1993b: 1330; Tucker 1998: 321); subfamily Ranininae (Serène & Umali 1976: 34) .

Like in the previous subsections, some authors used also this nomen at a rank higher than superfamily. But all these nomina were connected by coordination to the nomina of their included taxa, i.e., to De Haan, 1839, thus within the family-series: “subsection” Raninoida ( Martin & Davis 2001: 49, 51, 74; Schweitzer et al. 2010: 70); “section” Raninoida ( Martin & Davis 2001: 74; Ahyong et al. 2007: 582, 584, fig. 4; Ahyong, Naruse, Tan & Ng 2009: iv, 27, 135; Ng, Shih, Tan, Ahyong & Ho 2009: 16, 19, fig. 5; De Grave et al. 2009: 28; Karasawa, Schweitzer & Feldmann 2011: 534; Ahyong et al. 2011: 28); “subsection” Raninoidia (Guinot et al. 2008: 712; Van Bakel, Guinot, Artal, Fraaije & Jagt. 2012: 8, tables 1, 2). Schweitzer et al. (2010), such as Martin & Davis (2001), ascribed their section Raninoida (comprising Raninoidea and Cyclodorippoidea ) to the Eubrachyura, this section thus corresponding to Archaeobrachyura Guinot, 1977 (see Monophyletic Podotremata).

The question is whether the nomen “Archaeobrachyura” (explicitly referred to include superfamilies), which is unavailable in the family-series, is available in the class-series.

The nomen “ Notopterygia ” Latreille, 1831 ( Latreille 1831: 368) was established within the family-group Macrouri for a tribe of crustaceans with legs ending in “fins” and arranged into two rows, the posterior being dorsal (“ tous les pieds … à la fois terminés en nageoire et disposés sur deux rangs, les deux ou quatre postérieurs étant dorsaux ”). It included Ranina ranina (as Albunea scabra Fabricius ), Notopus dorsipes ( Linnaeus, 1758) (as Albunea dorsipes Fabricius, 1798 ), and an unnamed fossil species, corresponding to † Lophoranina aldrovandii (Ranzani, 1818) . It corresponds to our current Raninidae , in which the P2–P5 are modified for burying and swimming ( Van Bakel, Guinot, Artal, Fraaije & Jagt 2012). The nomen and/or diagnosis were cited by Jourdan (1834: 147), Lucas (1840: 154, 155), Bate (1888: 4, table), and Stebbing (1908: 17; 1922: 108). The nomen Notopterygia is in the same case as the two preceding tribes of Latreille (1831), Notopoda and Hypophthalma (see above). All based on a morphological character, these nomina were introduced in a publication where other nomina at the same tribe rank (e.g., Hippides, “ Hippides ”) belong in the family-series of Brachyura . Thus, Notopterygia , as Notopoda and Hypophthalma, cannot be used for a class-series taxon and is not avalaible for a new nomen in the desired class-series.

Bourne (1922b: 55, footnote) introduced the tribe Gymnopleura at a rank “ equivalent to the Dromiacea , Brachygnatha, and the rest of the Oxystomata ”, thus belonging in the class-series. The nomen Gymnopleura was first proposed by Bourne in an unpublished report to the Linnean Society (December 1921). Stebbing (1922: 108), who had read “in the report of the Linnean Society's meeting […] the abstract of an elaborate and highly important essay by Prof. G. C. Bourne on ‘The Raninidae : A Study in Carcinology’ ”, simply and briefly remarked that the nomen Gymnopleura was a junior synonym of the nomen Notopterygia (this last nomen being quoted by Stebbing 1908: 17). In a letter to the Editor of Nature, Bourne (1922a: 108) wrote that “it seems that my proper course will be to withdraw the nomen ‘Gymnopleura’ and substitute that of ‘ Notopterygia , Latreille’ in an addendum to the printer paper”. Bourne (1922b: 55, footnote) nevertheless eventually kept the nomen Gymnopleura , the adoption of Latreille’s name risking “confusion rather than perspicuity”. Bourne was right in do not replacing Gymnopleura by Notopterygia (see above under Notopterygia ). The availability of a nomen being not affected by inappropriateness (Code, Art. 18), the nomen “ Gymnopleura ”, which denotes a character not possessed by the extinct †Palaoecorystoidea and oldest Raninoidea that are not gymnopleure, is not to be rejected. The nomen Gymnopleura was used by a great number of modern authors but was progressively abandoned as a junior synonym of Raninoidea De Haan, 1839 (see Subsection Gymnopleura : Raninoidea and †Palaeocorystoidea).

The podotreme section Raninoida with the authorship “Ahyong et al. (2007)” was recognised by Karasawa, Schweitzer & Feldmann (2011: 534), and Schweitzer, Feldmann & Lamanna (2012: 148). Luque et al. (2012: 407, table 1) used alternatively “Section Raninoida Ahyong et al., 2007” and (p. 408) “Section Raninoida De Haan, 1839”. The authorship “Ahyong et al. (2007)” was not recognised by Ahyong, Naruse, Tan & Ng (2009: 135; 2011:186), who continued to attribute the nomen to De Haan (1839), in expressly mentioning “De Haan, 1839” and thus still referring to the family-series. Similarly, this authorship was not used by Van Bakel, Guinot, Artal, Fraaije & Jagt (2012), who used the nomen Raninoidia in their major revision of the crabs belonging to this subsection, and by recent authors (e.g., Low & Tan 2012), who continued to apply the authorship and date “De Haan 1839” instead of “Ahyong et al. 2007”. The nomen Raninoida of Karasawa, Schweitzer & Feldmann (2011: 534) credited with the authorship “Ahyong et al. (2007)” belongs in the family-series. The nomen Gymnopleura Bourne, 1922 , that has priority, is available for this taxon in the class-series.