Gecarcinus lagostoma H. Milne Edwards, 1837

Ng, Ngan Kee, Rodríguez Moreno, Paula A., Naruse, Tohru, Guinot, Danièle & Mollaret, Noémy, 2019, Annotated type-catalogue of Brachyura (Crustacea, Decapoda) of the Muséum national d’Histoire naturelle, Paris. Part II. Gecarcinidae and Grapsidae (Thoracotremata, Grapsoidea), with an Appendix of pre- 1900 collectors, Zoosystema 41 (7), pp. 91-130 : 99

Gecarcinus lagostoma H. Milne Edwards, 1837

( Fig. 2E )

Gecarcinus lagostoma H. Milne Edwards, 1837: 27 (see Remarks). — H. Milne Edwards in Fréminville, 1835 (footnote): 218 (nomen nudum).

CURRENT TAXONOMIC STATUS. — Johngarthia lagostoma (H. Milne Edwards, 1837) (see Türkay 1970: 345), accepted recombination.

LECTOTYPE (designated by Türkay 1973: 96). — MNHN-IU-2000-3750 (= MNHN-B3750 ), ♂ 63.7 × 82.4 mm (measurements by Türkay 63 × 81 mm),? Australia (inaccurate locality; in fact, Brazil, see Remarks), coll. Quoy and Gaimard, M. Türkay revision VI.1972. — Original label: “ Gecarcinus lagostoma M. Edwards ,?Australie, MM. Quoy et Gaimard”. Additional label: “ Lectotype! Gecarcinus (Johngarthia) lagostoma H. Milne-Edw., 1837 , ♂, Révision M. Türkay VI.1972 ”.

PRESERVATION OF THE LECTOTYPE. — Dry. Carapace with a fissure radiating from the cardiac region to hepatic region.

PARALECTOTYPES (designated by Türkay 1973: 96). — MNHN-IU- 2000-3748 (= MNHN-B3748), 1♀ 73.9 × 95.5 mm, same data as lectotype. — MNHN-IU-2000-3749 (= MNHN-B3749), 1♀ 73.4 × 97.2 mm, same data as lectotype .

PRESERVATION OF THE PARALECTOTYPES. — Dry.

REMARKS

The binomen Gecarcinus lagostoma introduced in a footnote by H. Milne Edwards in Fréminville (1835: 218) is a nomen nudum since it is not accompanied by a description or indication of the taxon it represents. Later, H. Milne Edwards (1837: 27) recorded that the specimen of Gecarcinus lagostoma was collected by Quoy & Gaimard in “Australasia” (and not in Australia), and he (H. Milne Edwards 1837: 25) described in the same paper Gecarcoidea lalandii from Brazil. Ortmann (1894: 739, as G. lalandei ) considered inexact the origin of Gecarcoidea lalandii , whereas Ortmann (1897: 338) and then Bouvier (1907: 498) considered inexact the type locality of Gercarcinus lagostoma (see also Tesch 1918; Tweedie 1947; Tavares 1989; Lai et al. 2017). As effectively Johngarthia lagostoma and G. lalandii were currently known from islands of the southern Atlantic Ocean and from the Indo-West Pacific regions, respectively, Türkay (1970: 346) concluded that H. Milne Edwards (1837) switched the collecting records of Gecarcinus lagostoma and Gecarcoidea lalandii , or, perhaps, the labels were exchanged during the same expedition. The diagnosis of G. lagostoma conforms, however, with the specimens of the type series (see also Rathbun 1918: 361, under Gecarcinus lagostoma ; 1918: 365, under? Gecarcoidea lalandii ; Türkay 1973: 96). Thus, the locality “Australasia” of the lectotype and paralectotypes must be recognised as inaccurate, and Brazil must be considered the type locality of Gecarcinus lagostoma , whereas “Australasia” is the original type locality of Gecarcoidea lalandii . Lai et al. (2017: 410, 416, figs 5E, 9D) have recently selected a fresh male specimen 64.2 × 88.8 mm from Quang Nam, central Vietnam collected in 2009, as the neotype of G. lalandii (ZRC 2010.0321).

Johngarthia lagostoma is only known from Ascension Island in the South Atlantic and from three islands off Brazil ( Trinidad, Fernando de Noronha, Atol das Rocas), western Atlantic ( Melo 1996; Hartnoll et al. 2006; Hartnoll et al. 2010: fig. 1).

The differences between the measurements by Türkay (63.0 × 81.0 mm) and ours (63.7 × 82.4 mm) are due to the restoration of the lectotype in the 1990s.

Figures

FIG. 2. — A, Cardisoma urvillei H. Milne Edwards, 1853, MNHN-IU-2000-3735 (= MNHN-B3735),lectotype, ♂; B, Discoplax gracilipes Ng & Guinot, 2001, MNHN- IU-2014-11214 (= MNHN-B26950),paratype,♀; C, Discoplax longipes A.Milne-Edwards,1867,MNHN-IU-2000-3763 (= MNHN-B3763),lectotype,♂; D, Gecarcinus digueti Bouvier,1895,MNHN-IU-2000-10951 (= MNHN-B10951),holotype,♂; E, Gecarcinus lagostoma H. Milne Edwards,1837,MNHN-IU-2000-3750 (= MNHN- B3750), lectotype, ♂; F, Gecarcinus lateralis Fréminville in Guérin-Méneville, 1832, MNHN-IU-2000-3758 (= MNHN-B3758), neotype, ♂; G, Gecarcinus nobilii Perger & Wall, 2014, MNHN-IU-2014-11211 (= MNHN-B12314), paratype, ♀; H, Pelocarcinus cailloti A. Milne-Edwards, 1890, MNHN-IU-2000-3751 (= MNHN- B3751), holotype, ♂. Scale bars: A, E, 5 cm; B-D, F-H, 2 cm.