The type of the land crab Cardisoma hirtipes Dana, 1851 (Crustacea: Brachyura: Gecarcinidae).

In describing a new species of land crab, Discoplax celeste, from Christmas Island, eastern Indian Ocean, Ng & Davie (2012: 95) selected a neotype for the related Discoplax hirtipes (Dana, 1851), originally described from Fiji as a species of Cardisoma Latreille, 1828. They commented that the type material was no longer extant and a neotype was necessary to stabilise the taxonomy of the species and its allies. The neotype they selected was a recently collected male specimen (64.2 × 53.0 mm, Zoological Reference Collection of the Raffles Museum of Biodiversity Research (now the Lee Kong Chian Natural History Museum), National University of Singapore, ZRC 2010.0415) from Fiji, with colour information as well as fresh tissues that could be used for genetic studies. Evans (1967: 410), however, had listed a syntype specimen of Cardisoma hirtipes in The Natural History Museum (NHM) (then the British Museum (Natural History), London)with the catalogue number 1861.44. The neotype selection of Ng & Davie (2012) thus appears to be unwarranted. Türkay (1974: 233), in revising the family, also listed among his material examined the following: “Südsee, Viti (1 Go/1 des Holotypus von Cardisoma hirtipes DANA 1851)”. No other data was provided, consequently it was unclear whether any specimen or only the gonopod was actually examined and where it was deposited. There was no other mention of this material in the text. Michael Türkay (in litt. 14 November 2012 to PKLN) explained that no holotype was examined. The specimen referred to in his revision was the one listed in Evans (1967). In the late 1970s, Türkay had written to Ray Ingle, Crustacea Section, NHM, about the specimen. Ingle confirmed that the type was a female measuring 72.0 × 67.0 mm and he sent photographs to Türkay for study. Türkay, after examining the photographs, replied: “Thank you very much for sending me the paralectotype of C. hirtipes, which I only got to examine now. Indeed, the specimen belongs to carnifex rather than the species for which hirtipes is currently used and so it is good to designate it as Paralectotype. I will probably publish a short note on this lectotype selection ...” (in litt. 22 February 1980). This note was never published nor was the information reflected in subsequent papers. The type female specimen in question has since been rehydrated and is now part of the NHM wet collection. It was recently examined and Türkay is correct in that the female (see Fig. 1C–F) is Cardisoma carnifex (Herbst, 1796) and not C. hirtipes. If this specimen is accepted as a syntype of Cardisoma hirtipes Dana, 1851, this female should be selected as the lectotype. This would result in Cardisoma hirtipes Dana, 1851, becoming a subjective junior synonym of Cardisoma carnifex (Herbst, 1796) and a new name would need to be established for Discoplax hirtipes, a widely distributed western Pacific species (Türkay 1974; Ng & Davie 2012). However, the female specimen of Cardisoma hirtipes in the NHM collection is nevertheless not considered to be a type specimen. In describing Cardisoma hirtipes, Dana (1851: 253, 1852: 376) listed only one male specimen measuring 58.4 × 47.5 mm from Viti [Fiji] and it was figured by Dana (1852: pl. 24, fig. 4). This indicates that Dana probably had only one specimen, although it is possible he had material not mentioned. Interestingly, William Stimpson, who had material of Dana at his disposal, made the following comment in his remarks of Cardisoma hirtipes: “We can discover no essential difference between the Loo Choo [now Okinawa] specimen and those described by Dana from the Fiji Islands ...” (Stimpson 1907: 111). This statement suggests Dana (and Stimpson) had more than one specimen of C. hirtipes from Fiji although it is uncertain whether all were types. The supposed NHM type specimen of Cardisoma hirtipes is not the specimen treated by Dana (1851, 1855), being of the wrong sex and larger in size. The specimen figured by Dana (1855; also see Fig. 1A, B) agrees well with what is here defined as Discoplax hirtipes, but not Cardisoma carnifex. Even though these specimens are females and