Identity of Eriocheir recta (Stimpson, 1858) (Decapoda: Brachyura), with Description of a New Mitten Crab from Taiwan

A review of the genus Eriocheir De Haan, 1835 and related genera, with the description of a new genus and a new species (Brachyura, Grapsoidea, Varunidae)

“…Eriocheir recta (Stimpson, 1858) now becomes a subjective junior synonym of E. japonica de Haan, 1835." As those authors (Chan et al, 1995) already indicated, their neotype can with certainty be identified as E. japonica (De Haan, 1835), which means that the name Eriocheir recta Stimpson, 1858 has indeed become a junior synonym of Eriocheir japonica (De Haan, 1835).…”

“…The status of the nominal species Eriocheir recta Stimpson, 1858 has been that of a species inquirenda, until a neotype was established to define its name, viz., by Chan et al (1995). As Stimpson's (1858) type-material is no longer extant (R. Lemaitre, USNM, in litt.)…”

“…In an obvious attempt at solving at least the nomenclatural problem of a nominal species, E. recta Stimpson, 1858, with an uncertain status, Chan et al (1995) designated a neotype for this E. recta. Having done so, they remarked (Chan et al, 1995: 303): "As all the available evidence shows that the type of E. recta is likely to be a juvenile female of E. japonica, a male (48.0 mm cw.…”

“…Although Chan et al (1995) have undoubtedly made an effort in selecting a neotype that they considered to approach the identity of the descriptions by Stimpson (1858Stimpson ( , 1907 as closely as possible, the establishment of a neotype only has nomenclatural consequences, not taxonomic ones. This means that, while now the name Eriocheir recta has got an unambiguous meaning, the actual status of the material on which Stimpson's (1858Stimpson's ( , 1907 descriptions are based still remains unresolved: at least, in the opinion of the present author, who has found sufficient morphological characteristics in those descriptions to keep the form described by Stimpson apart from the other species described in the genus Eriocheir and its close relatives, albeit now without a species name.…”

“…The mitten crabs (Brachyura, Varunidae, Varuninae) as currently conceived (e.g., Naser et al, 2012), would allegedly comprise six species belonging to three genera, i.e., Eriocheir japonica (De Haan, 1835), E. hepuensis Dai, 1991, E. ogasawaraensis Komai, Yamasaki, Kobayashi, Yamamoto & Watanabe, 2006, E. sinensis H. Milne Edwards, 1853, Neoeriocheir leptognatha (Rathbun, 1913), and Platyeriocheir formosa (Chan, Hung & Yu, 1995). In the present study, however, it has turned out through exact examination and detailed comparison of the external morphological characters of these forms, including the male Plp1, that in the opinion of the present author they are to be reclassified into four genera including one new genus, and seven species including one new species, while one species, currently unnamed, remains as a species inquirenda.…”