Diogenes holthuisi Asakura & Tachikawa, 2010

Rahayu, Dwi Listyo & Osawa, Masayuki, 2012, Hermit crabs (Crustacea: Decapoda: Diogenidae) from the KUMEJIMA 2009 Expedition, Japan *, Zootaxa 3367 (1), pp. 176-190 : 181

Diogenes holthuisi Asakura & Tachikawa, 2010

( Fig. 1B )

Diogenes holthuisi Asakura & Tachikawa, 2010: 135 , figs. 1–5.

Material examined. 1 ovig. female 1.3 mm, Stn. Dredge 2, 26°23.147ʹN, 126°44.931ʹE, 9 November 2009, 70 m (RUMF-ZC-1644).

Remarks. This species is characterized by the short, distally bifid antennal acicle without dorsal and dorsomesial rows of spines ( Asakura & Tachikawa 2010: fig. 1A, a). The specimen in this study agrees well with the original description except the shield is longer than broad and the ocular peduncles are prominently inflated basally. Asakura & Tachikawa (2010) stated that the shield is as long as broad and the ocular peduncles are only slightly inflated basally in the type material. Furthermore, the lateral and mesial surfaces of the dactyls of the second and third pereopods lack longitudinal sulci in the present specimen are unlike the type material. These differences are likely to be intraspecific variation because the intraspecific variations of particular characters are known to be high in the genus Diogenes as indicated by McLaughlin (2002c).

Colour. Shield white, ocular peduncles reddish-pink, corneas black with a greenish tinge. Left cheliped white with brown spot near articulation of dactyl and palm; right cheliped white with pinkish-red band on articulation of palm and carpus; ischium of both chelipeds red pinkish. Ambulatory legs alternately transparent and brown; meri reddish-brown.

Distribution. Ogasawara Island and now recorded from Kume Island; 3– 70 m.

Figures

FIGURE 1. A, Dardanus brachyops Forest, 1962, female, 4.09 mm, Stn. Dredge 23; B, Diogenes holthuisi Asakura & Tachikawa, 2010, ovig. female 1.27 mm, Stn. Dredge 2; C, Diogenes leptocerus Forest, 1956, male, 2.4 mm, Stn. Intertidal 4 (right third pereopod missing); D, Diogenes pallescens, female ovig. 2.35 mm, Stn Dredge 44; E, Paguristes macrops Rahayu & Forest, 2009, male, 3.45 mm, Stn. Dredge 23 (left cheliped and right third pereopod missing); F, Pseudopaguristes laurentae Morgan & Forest, 1991, male, 2.54 mm, Stn. Dredge 78.