Neopalicus jukesii ( White, 1847 )

Takeda, Masatsune & Tachikawa, Hiroyuki, 2015, Crabs of the families Palicidae and Crossotonotidae (Crustacea, Decapoda, Brachyura, Palicoidea) from the Ogasawara Islands, Japan, with the description of a new species, Zootaxa 3918 (1), pp. 141-150 : 142-143

Neopalicus jukesii ( White, 1847)

( Fig. 1A )

Selected synonymy:

Cymopolia jekesii White 1847: 338 , pl. 2 fig. 1.— Miers 1874: 3, pl. 3 fig. 4. Cymopolia carinipes Paul ′son 1875: 79, pl. 9 fig. 4.

Palicus jukesii — Alcock 1900: 451.— Calman 1900: 29, pl. 1 figs. 9-13.— Rathbun 1911: 240, pl. 19 fig. 9. Palicus carinipes — Holthuis 1977: 181, fig. 2.

Neopalicus jukesi — Moosa & Serène 1981: 42, fig. 7, pl. 2 fig. C. Neopalicus jukesii — Castro 2000: 550 (in key), 554, figs. 39b, 40b, c, 41c. (synonymy)

Material examined. West of Hakidashihama, Ani-jima I., Ogasawara Is., 6 m; 1 male (cb 5.8 mm, cl 5.3 mm), CMNH −ZC 02475; April 9, 1995; H. Takchikawa leg.

TR /V Seiyo Maru (Tokyo University of Marine Science and Technology) 1995 cruise, sta. 1 (27° 0 6.53'N, 142°10.78'E— 27° 0 7.61'N, 142°10.92'E, 62- 41 m), west of Ani-jima I., Ogasawara Is.; 1 ovigerous female (cb 8.7 mm, cl 7.8 mm) without chelipeds and ambulatory legs, NSMT-Cr 22985; June17, 1995.

Remarks. Neopalicus jukesii is the type species and one of the two representatives of Neoplicus. As discussed in detail by Castro (2000), the two species of Neopalicus , N. jukesii ( White, 1847) , and N. contractus (Rathbun, 1902) , are distinguished from the somewhat similar Palicoides , by rounded tubercles on the eye peduncle (thin crescent-shaped process in Palicoides ), the expanded anterior margins of the second and third ambulatory propodi as thin keels (no conspicuous enlargement in Palicoides ), and the slender second and third antennal segments without long setae (with many long setae in Palicoides ).

The morphological differences of two congeneric species were summarized in detail by Castro (2000) as follows: 1) the carapace is widest at level of the second anterolateral tooth in N. jukesii , but at the first anterolateral tooth in N. contractus , 2) the basal antennal segment is provided with two wing-like processes in N. jukesii , whereas they are scale-like in N. contractus , and 3) two pointed tips of the first male pleopod appear as one in N. jukesii , two in N. contractus .

Castro (2000) examined a female from the Ogasawara Islands and noted the strongly developed tubercles of the eye peduncles, chelipeds, carapace and other characters. Comparing the present material ( Fig. 1A ) with a female from New Caledonia ( Castro, 2000: fig. 39b), it is clear that the dorsal surface of the carapace appears to be rough, with clusters of granules in the specimen from the Ogasawara Islands. The first pleopod of a male from the Ogasawara Islands examined herein, however, is very close to that of a male from New Caledonia shown by Castro (2000: fig. 41c), and thus it is reasonable that the difference in the specimens from the Ogasawara Islands is the result of individual variation, and that Japan is within the distributional range of N. jukesii .

Distribution. Widely distributed in the Indian Ocean from the Red Sea and Madagascar to Australia, and in the western Pacific Ocean from Indonesia northward to Japan.

Figures

FIGURE 1. A, Neopalicus jukesii (White, 1847), male (cb 5.8 mm, cl 5.3 mm), CMNH − ZC 0 2475. B, Crossotonotus spinipes (De Man, 1888), immature female (cb 9.5 mm, cl 8.5 mm), NSMT-Cr 22987. C, Pleurophricus stellatus sp. nov., male (cb 5.7 mm, cl 5.2 mm), holotype, NSMT-Cr 22988.