Trapezia tigrina Eydoux & Souleyet, 1842

Boyko, Christopher B., Mendoza, Jose C. E. & Castro, Peter, 2017, New records of coral-associated crabs (Decapoda: Brachyura: Carpilioidea, Trapezoidea) from Easter Island, Zootaxa 4216 (5), pp. 487-494 : 490-491

Trapezia tigrina Eydoux & Souleyet, 1842

? Trapezia danai [sic]— Garth 1973: 315, 321, 322, 329; Retamal 1981: 33, fig. 178 (list); Castilla & Rozbaczylo, 1987: 209 (list); Retamal & Arana 2016: 23 (list); Escalante & Arancibia, 2016: 81 (list).

? Trapezia tigrina — Poupin 2003: 7, 30 (list); Retamal & Moyano, 2010: 315 (list); Retamal & Arana 2016: 23; Escalante & Arancibia, 2016: 81 (list).

Geographical distribution. Indo-West Pacific (Castro et al. 2004).

Remarks. This species has only been reported once from Easter Island , as Trapezia danai [sic], and all records from subsequent publications are based on that single female identified by Garth (1973). Trapezia danae (not danai , see below) is now considered a synonym of T. tigrina (see Castro et al. 2004; Ng et al. 2008). Garth (1973) stated that he was not sure of the identity of the specimen he had on hand, and it remains unclear if the species actually occurs on Easter Island. The location of Garth’s unique specimen is unknown. Based on the difficulties in identifying preserved specimens of Trapezia , it is quite possible that Garth’s (1973) record was actually T. punctimanus because both are characterized by having small dots, although those of T. punctimanus are restricted to the chelipeds ( Castro 1997: pl, 1, fig. E), whereas those of T. tigrina are distributed throughout the carapace and pereiopods (Castro et al. 2004: pl. 3, fig. E).

Trapezia danae is the correct original spelling of the species name as there is nothing in Ward (1939) to indicate any kind of inadvertent error in the name’s formation (see ICZN Article 32.5). Ward (1939) probably erred when forming the species name with a feminine ending, unless he was naming it after Dana’s wife or another female with the Dana surname; that does seem unlikely, however, and there is nothing in his publication to indicate why he chose the feminine formation of the name. Subsequent spellings of the species name as Trapezia danai (e. g., Garth 1964; Knudsen 1967; Serène 1971; Garth 1974) are therefore unjustified emendations. Spelling of the name was changed in these publications without any of the authors who used “ danai ” providing an explanation as to why they were emending the name; perhaps it seemed self-evident but it was still unjustified. It should be pointed out that there are proportionally fewer unjustified emendations of Pocillopora danae Verrill, 1864 , which is a much more often cited species (before it was synonymized with P. verrucosa (Ellis & Solander, 1786)) (but see Rehberg (1892) for a rare example of P. danai ). In fact, Knudsen (1967) used T. danai but left P. danae unaltered.