Grapsus albolineatus Lamarck, 1818

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 : 102

Grapsus albolineatus Lamarck, 1818

Grapsus albo-lineatus Lamarck, 1818: 249 .

CURRENT TAXONOMIC STATUS. — Grapsus albolineatus Lamarck, 1818 .

TYPE MATERIAL. — None extant.

REMARKS

The binomen “ Grapse albo-lineatus ” (“grapse rayé de blanc” or white-striped grapse) has been introduced by Latreille, in Milbert (1812: 275) but Grapsus albolineatus is usually credited to Lamarck (1818: 249, as Grapsus albo-lineatus , “grapse raies-blanches”). As is often the case, Latreille in Milbert (1812) and Lamarck (1818) were based on the same material, namely a crab collected by Mathieu from Mauritius (= Île de France; see also Latreille 1825: 148), and referred to the same species. Latreille in Milbert (1812: 275) wrote “ grapse ” (“Ce sont les grapses de M. Lamarck” [These are the grapses of M. Lamarck]). Although “ G. albo-lineatus ” is a binominal combination with latinised species names, the absence of any diagnosis makes it not available (see the discussion below). The genus name Grapsus belongs to Lamarck (1801: 150), with Cancer grapsus Linnaeus, 1758 as type species by tautonomy (see also designation by Latreille 1810: 422).

Grapsid species cited in Latreille in Milbert (1812: 275), i.e., Grapsus albolineatus , G. erytrhocheles , G. tuberculatus and G. tessellatus , correspond to two different nomenclatural situations. Grapsus tessellatus “grapse damier” (“checkered grapse”) is described in a few lines: this constitutes a diagnosis making the name available: consequently, it can be credited to Latreille in Milbert (1812) as Lybia tessellata (see Guinot 1976). The case is different for the three other “ grapses ”: G. albo-lineatus “grapse rayé de blanc” (white-striped grapse); G. erytrhocheles “grapse à pinces rouges” (grapse with red claws), G. tuberculatus “grapse tuberculé” (tuberculated grapse). In most French and German scientific works at this time, the Latin name was accompanied by its translation in French (e.g. Latreille 1806; Lamarck 1818; H. Milne Edwards 1834, 1837), or in German, (e.g. Herbst 1782 -1804). These specific spellings are only the latinisation of the names depicting morphological (shape, colour, ornamentation), behavioural, geographical and other features, by simple juxtaposition of both names. This simple translation of the names is not enough to constitute a diagnosis and to make the taxa available, and does not correspond to a brief description. These names cannot satisfy the requirement of Article 12.1 of the Code stipulating that (for the names published before 1931) to be available a taxon must be accompanied by a description (even if only the colour) or a definition of the taxon that it denotes, or by an indication. According to Ng et al. (2008: 22) these three species were “defined by their colour or shape”, but this is not the case and these names are not available.

Moreover, Ng et al. (2008: 22) have treated the three above-mentioned grapses in the same manner as the case of Grapsus tessellatus , and credited Grapsus albolineatus , Grapsus erytrhocheles and Grapsus tuberculatus , like G. tessellatus , to Latreille in Milbert (1812). It is an erroneous generalisation: G. tessellatus is an available name with the authorship of Latreille in Milbert (1812), whereas the other three names are clearly nomina nuda. Grapsus albolineatus belongs to Lamarck, 1818, G. erytrhocheles is not available (or at least corresponds to a species inquirenda); G. tuberculatus must be credited to Lamarck (1818: 247, as Plagusia tuberculata ) ( Schubart & Ng 2000: 327, 334, fig. 3A).

To avoid ambiguity, a point that requires discussion is the meaning of “vernacular”. According to the English glossary of the Code ( ICZN 1999: 110) a vernacular name is “A name of an animal or animals in a language used for general purposes as opposed to a name proposed only for zoological nomenclature”, whereas a zoological name is “The scientific name of an animal taxon in binominal nomenclature”. Thus in French scientific works at the period of Henri Milne Edwards (1834, 1837), the new taxa are proposed in a scientific context and are not vernacular names, conversely to the views of most carcinologists (including Ng et al. 2008: 20).

The type material from Mauritius collected by Mathieu was not found in the MNHN collection. A neotype should be fixed for Grapsus albolineatus , preferably from the type locality, Mauritius or its proximity (Code, Art. 75.3.6), as it is considered the senior synonym of numerous species (see Banerjee 1960: 147, 154; Holthuis 1977: 145, 147), such as G. strigosus (Herbst, 1799) , from the Indian Ocean; G. (Goniopsis) flavipes MacLeay, 1838 , from Cape of Good Hope; G. peroni H. Milne Edwards, 1853 , from Australia (see below); and G. longipes Stimpson, 1858 , from Kikaishima, southern Japan, and Hong Kong ( Davie 2002). The type locality “ les mers de l’Ile-de-France” and the occurrence of this species on the east coast of Africa was questioned by Crosnier (1965: 17) but according to Holthuis (1977: 147) it is one on the most common and conspicuous crabs of the Red Sea.

A neotype designation is unfortunately not possible at this time because the MNHN collection does not possess any material from Mauritius or a nearby locality (Code, Art. 75.3.6).

Grapsus granulosus H. Milne Edwards, 1853 , from the Red Sea, identified as G. albolineatus by some authors (e.g. Banerjee 1960; Davie 2002), is regarded as distinct by others (e.g. Crosnier 1965; Holthuis 1977; Vannini & Valmori 1981; Zaouali et al. 2007; Ng et al. 2008); see below.