Carcinoplax longipes (Wood-Mason, 1891)

Castro, Peter, 2007, A reappraisal of the family Goneplacidae MacLeay, 1838 (Crustacea, Decapoda, Brachyura) and revision of the subfamily Goneplacinae, with the description of 10 new genera and 18 new species, Zoosystema 29 (4), pp. 609-774 : 636-637

Carcinoplax longipes (Wood-Mason, 1891)

Nectopanope longipes Wood-Mason in Wood-Mason & Alcock, 1891: 262 [Andaman Sea]. — Alcock & Anderson 1895: pl. 14, fig. 7 [Andaman Sea].

Carcinoplax longipes – Alcock 1899: 71; 1900: 302 [in key], 303 [southern India, Andaman Sea]. — Alcock & Anderson 1899: 5 [in list]. — Doflein 1904: 117, 306 (table) [Andaman Sea]. — Tesch 1918: 154 [in list]. — Serène 1968: 90 [in list]. — Sakai 1969: 270 [in list]. — Serène & Lohavanijaya 1973: 62 [in list], 65 [in key], 68, pl. 14, fig. D [type material]. — Guinot 1989: 303 [discussion], fig. 26, pl. 10, figs A-C [Andaman Sea]. — Chen 1998: 266 [in key].

Pilumnoplax longipes – Miers 1886: 226 [in list].

Carcinoplax aff. longipes – Guinot 1989: 305, figs 27, 35, pl. 10, figs D-F [Philippine Is].

Carcinoplax sp. ( aff. longipes ) – Guinot 1989: 305, fig. 36, pl. 10, fig. G [Philippine Is].

Not Carcinoplax longipes – Sakai 1976: 524 [in key], 527, fig. 281. — Chen 1984: 189 [in key], 195, 197, fig. 6. — Miyake 1991: 220 [in list] [ Japan]. — Ikeda 1998: 15, 42, 135, pl. 55. — Takeda et al. 2006: 204 [in list] [ Japan] (= Carcinoplax specularis Rathbun, 1914 ). TYPE MATERIAL. — Photo of assumed “cotype” in Serène & Lohavanijaya (1973: pl. 14, fig. D), Investigator , stn 56 (Zoological Survey of India, Kolkata [Calcutta]).

TYPE LOCALITY. — Andaman Is, 403- 439 m.

MATERIAL EXAMINED. — India. Travancore coast, stn 232, 07°17.5’N, 76°54.5’E, Investigator, A. Alcock det., Indian Museum leg., 1 ♂, 1 ♀ ( USNM 46291). — Off Travancore coast, 787 m, Indian Museum leg., 1 ♀ ( BMNH 1955.4.4.5).

Philippine Islands. South China Sea, MUSORSTOM 1, stn CP 50, 13°49’N, 120°02’E, 415-510 m, 25.III.1976, 1 ♂ ( MNHN-B 10140).

MUSORSTOM 2, stn CP 36, 13°31’N, 121°24’E, 569-595 m, 24.XI.1980, 1 ♂ ( MNHN-B 10377), 1 ♂ ( MNHN-B 29832), 1 ♀ ( MNHN-B 29831), 1 ♂, 1 pre-adult ♀, 1 ♀ ( MNHN-B 29825). — Stn CP 44, 13°23’N, 122°21’E, 760-820 m, 26.XI.1980, 1 pre-adult ♂ ( MNHN-B 10269). — Stn CP 46, 13°26’N, 122°17’E, 445-520 m, 26.XI.1980, 1 ♂ ( MNHN-B 10264). — Stn CP 82, 13°46’N, 120°28’E, 550 m, 2.XII.1980, 1 ♀ ( MNHN-B 11578).

?Off Mindoro, Albatross, stn 5123, 13°12’N, 121°38’E, 517 m, 2.II.1908, 1 pre-adult ♀ ( MNHN-B 17729).

Visayan Sea, MUSORSTOM 3, CP 143, 11°29’N, 124°11’E, 205-214 m, 7.VI.1985, 1 pre-adult ♀ ( MNHN- B 16936).

DISTRIBUTION. — Southern India (Alcock 1899), Andaman Sea (Wood-Mason & Alcock 1891; Doflein 1904), and the Philippine Is ( Guinot 1989). Depth: 205- 820 m.

REMARKS

Examination of two specimens from southern India originally at the Indian Museum (female, cl 11.9 mm, cw 15.1 mm, pre-adult male, cl 8.5 mm, cw 11.4 mm; USNM 46291) allowed Guinot (1989: 303, fig. 26, pl. 10, figs A-C) to redescribe the species, but the description was based only on the female specimen. The second specimen, a pre-adult male, however, showed the most important characters outlined by Guinot for the female. It differed from the female in having only a slightly raised margin between the orbital margin and the first anterolateral tooth instead of a well defined rectangular tooth. The anterolateral teeth were thinner and more spiniform than those of the female. The G1 is thin and slender, the G2 slightly longer than the G1 and with two triangular spinules at the tip. The vulva of the female specimen was greatly enlarged, covered by a soft membrane except along the anterior margin, and occupying the whole breadth of thoracic sternite 6, all of which are characters shared by the species of Carcinoplax sensu stricto. The ambulatory legs (P2-P5) were long and relatively slender in both specimens so that the distal end of the merus of the folded P5 reached the tip of the second anterolateral tooth. The ambulatory legs of the female illustrated by Alcock & Anderson (1895: pl. 14, fig. 7), however, are not as long as in the Indian Ocean specimens examined here. A photograph of a male from the Zoological Survey of India indicated as a cotype ( Serène & Lohavanijaya 1973: pl. 14, fig. D), however, shows the long and slender ambulatory legs characteristic of the species.

Guinot (1989: 305) described a specimen from the Philippine Is (male, cl 18.2 mm, cw 25.0 mm; MNHN-B 10377) that showed some differences from the Indian Ocean specimens of C. longipes . It was listed separately as Carcinoplax aff. longipes ( Guinot 1989: 305, figs 27, 35, pl. 10, figs D-F). The carapace of the Philippine Is specimen was found to be, as correctly pointed out by Guinot (1989), slightly less inflated than the Indian Ocean material of C. longipes , having a smooth dorsal surface (short tomentum in C. longipes ), smooth chelipeds (P1) (distinct granules on the dorsal surface of the propodus and dactylus in C. longipes ), and a distinct hook-like shape of the first anterolateral teeth (shorter, straighter in C. longipes ). Another difference is that the P1-P5 appeared longer and thicker in the Philippine Is specimen than in C. longipes . The differences, however, were not measurable: P5 merus length 0.7 cl and P5 merus width 0.2 cl in both populations. Two additional specimens from the Philippine Is (♂, cl 15.2 mm, cw 21.2 mm, MNHN-B 10140; ♀, cl 12.3 mm, cw 17.6 mm, MNHN-B 11578) were found by Guinot (1989) to be intermediate between the Indian specimens and Carcinoplax aff. longipes . They were referred to as “ Carcinoplax sp. ( aff. longipes )” ( Guinot 1989: 305, pl. 10, fig. G). The dorsal surface of the carapace of both specimens had a short tomentum as in C. longipes but the second anterolateral teeth were more incurved as in C. aff. longipes . The most significant difference between the specimens from the Philippine Is and the two from the Indian Ocean that were examined is that the outer orbital angle was in the form of a distinct triangular tooth in the Philippine Is specimens, higher and therefore more conspicuous than in the Indian Ocean specimens. The examination of additional material from the Philippine Is has shown that the specimens previously identified by Guinot (1989) as Carcinoplax aff. longipes and Carcinoplax sp. ( aff. longipes ) be- long to C. longipes based on a comparison with the available Indian material.

The records of C. longipes from Japan by Sakai (1969, 1976) remain questionable since no illustrations were given and his specimens could not be examined, but the photograph of Ikeda (1998: 135, pl. 55) of Japanese material confirms it as C. specularis Rathbun, 1914 . The illustration of C. longipes by Chen (1984: fig. 6) shows that her specimen from the East China Sea most probably belongs instead to C. specularis .