Calcinus elegans (H. Milne Edwards, 1836)
Illustrations. - Male shield length 7.5 mm, Gambier, French Polynesia. Hawaii color variant (copyright J. Hoover). After Hoover, 1998. Ocular peduncles, color pattern. Left third P3, color pattern.
References. - Pagurus elegans H. Milne Edwards, 1836: 278 (type locality: New Guinea).
Calcinus elegans - Barnard, 1950: 437 (South Africa). - Fize & Serène, 1955: 40 (Vietnam). - Matzusawa, 1977: pl. 79, fig. 4 (Japan). - Takeda, 1982: 61 (Japan). - Miyake, 1982: 113 (Japan). - Haig & McLaughlin, 1984: 109 (Hawaii). - Wooster, 1984: 128 (Mariana). - Haig & Ball, 1988: 159 (Indonesia). - Nomura et al., 1988: 108 (Japan). - Morgan, 1991: 874 (Christmas & Cocos Islands, Australia). - Yu & Foo, 1991: 34 (Taiwan). - Gherardi & McLaughlin, 1994: 618 (Mauritius). - Jones & Morgan, 1994: 113, 115 (Australia). - Takeda, 1994: 194 (Japan). - Asakura, 1995: 355 (Japan). - Hoover, 1998: 253 (Hawaii, color variant). - Shih, 1998: 86 (Taiwan). - Asakura, 2002: 40 (type specimen, plus Japan, Mariana).
Shield and cephalic appendages. - Ocular scale with a single terminal spine.
Chelipeds (P1). - Upper margin of right chela tuberculated or spinous. Outer face of left palm regularly convex. Fingers of left chela with square-like tubercles on outer face.
Ambulatory legs (P2-P3). - Dactyl of P3 subequal to propodus or slightly shorter. Distal pilosity of P3 dense, forming a brush of setae.
Armament of telson. - Left lobe of telson with several spines disposed on posterior margin only (26). Right lobe with several spines (25).
Coloration. - Shield white or cream (to pale green). Ocular peduncle multicolored without narrow ring close to cornea. Detailed coloration of ocular peduncle: bright blue, with narrow dark ring proximally. Distal antennular peduncle yellow-orange (basal segments of peduncle and flagella of the same color). Distal antennal peduncle yellow-orange (same color on basal segments and flagellum). Chela uniformly colored, often grading to paler distally (dark green, turning to white; carpus of cheliped dark green). Ambulatory legs (P2 & P3) with spots and ring(s) (background sky blue; black spots distally, on dactyls and distal propodi, and black rings on basal segments).
Habitat. - Intertidal rocky shores.
Geographic distribution. - Widely distributed in the Indo-West Pacific: South Africa; Indian Ocean (Mauritius, Cocos & Christmas); Indonesia; New Guinea; Vietnam; Taiwan; Japan; Mariana; Hawaii; French Polynesia (Society, Tuamotu, Gambier). Indo-West Pacific.
Remarks. - A sibling species of C. elegans, C. orchidae, has been recently described from the Marquesas. The two species are mainly distinct by their color pattern (see under C. orchidae). In Hawaii, there is also a color variant of C. elegans, with yellow-orange background coloration on the ambulatory legs rather than sky blue on the typical C. elegans (see Images). However, as color pattern of the two forms is the similar, they have been kept under the same species.