Moloha alisae Guinot & Richer de Forges 1995

Moloha alisae Guinot & Richer de Forges, 1995

Figs 2, 3 C–D, 4B, 5C–D, 7–8, 11–12, 14C–D, 16, 17A

Moloha alisae Guinot & Richer de Forges, 1995: 389, figs 29e–f, 51i–k.

Moloha alisae – Ng et al. 2008: 41 (list).

Diagnosis

Carapace with pseudorostral and supraocular spines long, subequal; supraocular spine with distinct submedian accessory spine; gastric region with 3 major spines, surface between them smooth, unarmed; branchial regions gently convex; subhepatic region swollen, with 2 large dorsal and 2–4 small ventral spines; protogastric region with 2 major spines; basal antennal spine triangular, relatively broad; P2–P4 very long, slender, subcylindrical, merus with 6–10 spines on dorsal margin, outer surface with 1–9 small spines, ventral margin with 8–26 spines; P5 with 1–3 spines on dorsal margin, 2–4 small spines on outer surface, 2–5 spines on ventral margin, subchelate structure relatively longer, spines on flexor margin are spaced further apart, relatively smaller distally. G1 stout, short, groove on ventral surface median, dorso-median surface concave, distal part less rounded, opening relatively smaller, flap-like, not auriculiform, directed towards median part of sternum.

Material examined

SEYCHELLES: Holotype, ♂ (tcl 40.6 mm, cl 36.1 mm, tcw 33.9 mm, cw 29.7 mm), 16.4°34.7’ S, 56°25.6’ E, stn 3, 390– 410 m, coll. CEPROS Expedition, A. Intès, 22 Oct. 1987 (MNHN-IU- 2008-11077, ex MNHN-B 20289).

SOUTH AFRICA: 2 ♂♂ (tcl 80.3 mm, cl 67.7 mm, tcw 64.6 mm, cw 56.2 mm; tcl 78.9 mm, cl 67.5 mm, tcw [spines broken], cw 56.5 mm), Eastern Cape, Port Elizabeth, Bay World, off Kenton, coll. S. Warren, Jun. 2004 (ZRC 2008.1250).

Colour

In life, the carapace, chelipeds and ambulatory legs are orange with patches of white (Fig. 17A).

Distribution

The species was described from the Seychelles; the present record from South Africa is new.

Remarks

The holotype male of M. alisae is small (MNHN-IU-2008-11077; cl 36.1 mm, cw 29.7 mm) and, although the G1 and G2 are present, it is clearly still a juvenile. The male pleon is not domed (Fig. 7E) and the gonopods are still not strongly chitinised, being relatively soft (Figs 7C, 16 A–C). We have referred the two large specimens from South Africa (ZRC 2008.1250) to this species because it matches the holotype in most key aspects: the carapace shape is distinctly rectangular, the surfaces between the major spines on the gastric region are smooth and unarmed, the cardio-intestinal groove is deep, and P5 is long, reaching to the base of the pseudorostral spines when folded anteriorly. Another shared character is the proportionately longer P5 propodus of the subchelate structure, which has the teeth on the distal half of the flexor margin more widely spaced (Figs 11F, K, 12F, H–J). In M. grandperrini and M. tumida sp. nov., the P5 propodus is relatively shorter and the flexor margin has more closely arranged teeth of similar sizes (Figs 10F, 13I).

However, there are a number of differences which we believe are size-related and not significant at the species level. The branchial surfaces of the two large South African specimens are covered with relatively more spinules between the major spines (Figs 2B, 3D, 14D) compared to those on the holotype male (Figs 2A, 3C, 14C). In addition, the P5s of the two largest South African males are still relatively shorter than those of the holotype male from the Seychelles, reaching only to the base of the pseudorostral spines (Fig. 14D) and not to the median part of the spines (Fig. 14C). The armature of P2–P5 is substantially stronger in the two South African males (Fig. 12 B–D) compared to that on the holotype male (Fig. 11 B–D, G–I; Table 1). There is also a slight difference in the form of the distal part of the G1. In the large South African males, the distal part is more bulbous, with the opening relatively large (Fig. 16 D–E), while in the smaller Seychelles male, it is less swollen, with the opening smaller and more folded (Fig. 16 A–B). The chelipeds of the two South African males are typical of many large mature homolids, being elongated, stout, the surfaces granular and covered with dense setae (Fig. 8C, E). Those of the holotype male from the Seychelles (Fig. 7 E–F) clearly belong to a juvenile. As such, it is best to refer the two large South African specimens to M. alisae for the time being, at least until more material becomes available from the area, especially belonging to intermediate size-classes.

The presence of M. alisae in South Africa means that there are now two species of Moloha in its waters, the other being the type species, M. alcocki s. str ..

For additional comparisons, see the Discussion section.