Goneplax barnardi ( Capart, 1951 ) Castro, 2007

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 : 689-690

Goneplax barnardi ( Capart, 1951) n. comb.

( Fig. 27B )

Carcinoplax barnardi Capart, 1951: 170 , fig. 65, pl. 3, figs 5, 12 [ Gabon, Angola]. — Monod 1956: 340 [in key], 351, figs 456-461 [ Senegal]. — Forest 1963: 627, 628 [in list] [ Ivory Coast]. — Maurin 1968: 484 [in list] [ Western Sahara]. — Guinot 1969b: 526 [discussion]; 1971: 1081 [in list]. — Manning & Holthuis 1981: 160 [ Ivory Coast, Nigeria, Gabon]. — Guinot & Castro 2007: 25 [discussion] [ Congo, Angola].

[ Carcinoplax ] barnardi – Guinot 1989: 314 [in list] fig. 46 (part).

TYPE MATERIAL. — 1 ♂, 1 pre-adult ♂, 2 ♀♀ syntypes ( IRSNB 16808).

TYPE LOCALITY. — Off northern coast of Angola, 350- 420 m.

MATERIAL EXAMINED. — Congo (Democratic Republic). Pointe Noire, 05°00’S, 11°19’E, 405-410 m, A. Crosnier coll., 15.III.1967, 3 ♂♂, 2 ♀♀ ( MNHN-B 10107). — 05°06’S, 11°26’E, 345-355 m, 18.III.1967, 3 ovig. ♀♀ ( MNHN-B 10108).

Angola. Campagne ZAIANGO-BIOL 2, stn CP 09, 07°17.67’S, 12°04.67’E, 360-367 m, 29.VIII.2000, 2 ♂♂, 4 ♀♀ ( MNHN-B 27933).

DISTRIBUTION. — Western Atlantic along the west coast of Africa from Western Sahara and Cabo Verde Is to Angola. Depth: 200- 586 m.

REMARKS

Capart (1951: 172) described Goneplax barnardi n. comb. under Carcinoplax on account of the shape of the carapace, the relatively short eye peduncles, and “the other characteristics of the genus”. He agreed that Carcinoplax was nevertheless close to Goneplax and that the male first pleopods of his new species were difficult to be used as a diagnostic character. In contrast to Carcinoplax , G. barnardi n. comb. has longer eye peduncles, the dorsal margins of the ambulatory leg (P2-P5) meri are armed with an acute distal tooth (although present in C. spinosissima Rathbun, 1914 ), and the dactyli are slender and have a carina on each side. Sakai (1976: 531, as Carcinoplax barnardi ) mentioned that the species “seems to belong to Psopheticus , near P. insignis ” but without giving any explanations.

Goneplax barnardi n. comb. may be distinguished from G. rhomboides and G. clevai , which are also found along the West African coast, by the rounded anterolateral borders of its carapace and the presence of conspicuous tubercles on the subhepatic region ( Fig. 27B ). The borders are straight or nearly straight and the subhepatic region lacks large tubercles in G. rhomboides ( Fig. 27A ) and G. clevai (see Guinot 1989: fig. 45, as [ Carcinoplax ] barnardi ; Guinot & Castro 2007: figs 1-3). Also diagnostic is the length of its eye peduncles. They are much shorter in G. barnardi n. comb. (0.4 front width; Fig. 27B ) than in G. rhomboides , where it is as long as or slightly longer than the front width ( Fig. 27A ), or in G. clevai , where they are slightly shorter than the front width (0.8 front width). There are also probable differences in colour. Goneplax barnardi n. comb. was described as “rose bistre” (dark-brown pink) ( Capart 1951: 172), while G. rhomboides is known to have a “yellow to pale red, sometimes fringed with violet” carapace and “yellow to orange” chelipeds and ambulatory legs ( Ingle 1980: 109). Goneplax clevai was described by Barnard (1950: 285, as G. angulata ) as “pale pink, or salmon, or pinky-cream, carapace and chelipeds more or less vermiculate or mottled”. A freshly preserved specimen had irregular, purple-pink reticulations on the anterior portion of the carapace; the dorsal surfaces of the chelipeds and eye peduncles were light purplepink (see Guinot & Castro 2007: fig. 2B).

Figures

FIG. 27. — A, Goneplax rhomboides (Linnaeus,1758), ♂, cl 21.6 mm, cw 34.7 mm, Shoalstone Point, Brixham, Devon,UK, D. George et al. coll., 18 m (BMNH 1981.539); B, Goneplax barnardi (Capart, 1951) n. comb., ♂, cl 14.1 mm, cw 25.1 mm, off northern coast of Angola, Campagne ZAIANGO-BIOL 2, stn CP 09, 360-367 m (MNHN-B 27933).