Grapsus pictus Latreille, 1803

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 : 110

Grapsus pictus Latreille, 1803

( Fig. 5C )

Grapsus pictus Latreille, 1803: 69 , pl. 47, fig. 2; 1806: 33. — Lamarck 1801: 150 (nomen nudum); 1818: 248.

CURRENT TAXONOMIC STATUS. — Junior subjective synonym of Grapsus grapsus ( Linnaeus, 1758) (see A. Milne-Edwards & Bouvier 1900: 111; Rathbun 1918: 227; Banerjee 1960: 153; Griffin 1973: 423; Ng et al. 2008: 216).

NEOTYPE (by present designation). — MNHN-IU-2000-3409 (= MNHN-B3409), mature ♀ 31.6 × 33.3 mm, Grapsus grapsus Linné (= Grapsus pictus Latr. ), attacked by bopyrids, Martinique, coll. M. Rivière. — Original label: “ Grapsus grapsus Linné (= Grapsus pictus Latr. ), attaqué par les Bopyres , Martinique, M. Rivière ”.

PRESERVATION. — Dry. All pereopods detached.

REMARKS

The specific name pictus was introduced by Lamarck (1801: 150) when he established the new generic name Grapsus (its etymology is related to the ancient Greek grapsaios that means “crab”) in indicating “ Grapsus pictus . n. Cancer grapsus . Lin. ”, i.e., Cancer grapsus of Linnaeus (1758). As a specific description is lacking and there is no mention of any material or locality, the specific name pictus of Lamarck (1801) is a nomen nudum. Later, Lamarck (1818: 248) provided a description and a geographical origin “mers de l’Amérique méridionale” (seas of South America), still considering it a nomen for Cancer grapsus , now Grapsus grapsus ( Linnaeus, 1758) . Meanwhile, based on the same material as Lamarck (1818), Latreille (1803: 69, pl. 47, fig. 2) used the name Grapsus pictus in giving a short diagnosis and a figure of a specimen from the “îles de l’Amérique méridionale” (islands of South America) that he likewise referred to as the Cancer grapsus of Linnaeus. Therefore, the authorship of G. pictus is not Lamarck (1801) but Latreille (1803). Note that in his list of genera with the indication of their type species, called ‘genotypes’ (“ Tableau des genres avec l’indication de l’espèce qui leur sert de type ”), Latreille (1810: 422) quoted Cancer grapsus as the type (onomatophore) of the genus Grapsus , and not G. pictus (see also H. Milne Edwards 1836 -1844: pl. 22). G. grapsus ( Linnaeus, 1758) is the type species of Grapsus by tautonomy ( Manning & Holthuis 1981; Ng et al. 2008).

Grapus pictus of Latreille (1803) was considered an available nomen by most authors ( Saussure 1853: 362; Alcock 1900: 392; A. Milne-Edwards & Bouvier 1900: 111; Rathbun 1918: 227; Banerjee 1960: 153; Boyko 2000: 128; Ng et al. 2008: 216) who regarded the species as a junior subjective synonym of Grapsus grapsus . Grapsus pictus from Guam figured by Quoy & Gaimard (1824: 523, pl. 76, fig. 2) is Grapsus rudis H. Milne Edwards, 1837 (see below under this name).

The MNHN collection contains a sample with two specimens: a preadult female 26.2 × 32.4 mm, MNHN-IU-2000-1101 (= MNHN-B3409); and a mature female 31.6 × 33.3 mm, MNHN-IU-2000-3409 (= MNHN-B3409), dry, labelled “ Grapsus grapsus Linné (= Grapsus pictus Latr. ), attaqué par les Bopyres, Martinique, M. Rivière” [this collector is unknown according to the available information and thus is not included in the Appendix]. These individuals are parasitised by bopyrids, the preadult female on both sides and the mature female on the right side.

In the handwritten Catalogues of Crustacea by Latreille (LC1807, LC1814), two specimens, a male and a female, are cited without locality, date or collector: there is no mention of bopyrids ( Fig. 1B ). The figure of Grapsus pictus in Latreille (1803 : pl. 47, fig. 2) does not show any deformation of the carapace by a parasite but such an unnatural shape was perhaps not taken into account by the drawer. Even if Latreille (1803) could have confused the preadult female with a male, we do not have enough objective proof to consider that these specimens belong to the type series of Grapsus pictus . Consequently, for clarification purposes the designation of a neotype is justified.

Figures

FIG. 5. — A, Grapsus peroni H. Milne Edwards, 1853, MNHN-IU-2000-10934 (= MNHN-B10934), lectotype, ♂; B, Grapsus pharaonis H. Milne Edwards, 1853, MNHN-IU-2000-3439 (= MNHN-B3439),lectotype,♂; C, Grapsus pictus Latreille 1803,MNHN-IU-2000-3409 (= MNHN-B3409),neotype,♀; D, Grapsus plicatus H. Milne Edwards,1837,MNHN-IU-2000-3585 (= MNHN-B3585),lectotype,♀; E, Grapsus rudis H. Milne Edwards, 1837,MNHN-IU-2000-10875 (= MNHN-B10875), holotype, ♂; F, Grapsus webbi H. Milne Edwards, 1853, MNHN-IU-2000-3457 (= MNHN-B3457), lectotype, ♂. Scale bars: A, F, 2 cm; B, E, 5 cm; C, D, 10 mm.

FIG. 1. — A, First page of the handwritten “Catalogue of Articulated animals: Crustaceans, Arachnids, Insects, received, donated, exchanged or bought” (CAA), volume 1, with entries from 1826 to 1834; B, text of the page about Grapsus pictus Latreille, 1803 in the “Catalogue of Crustaceans, Arachnids and Insects ex- hibited in the gallery of the Muséum d’histoire naturelle de Paris” by P. A. Latreille 1814 (LC1814).