Intesius richeri Crosnier & Ng, 2004

Ahyong, Shane T., 2008, Deepwater crabs from seamounts and chemosynthetic habitats off eastern New Zealand (Crustacea: Decapoda: Brachyura), Zootaxa 1708 (1), pp. 1-72 : 42-43

Intesius richeri Crosnier & Ng, 2004

( Figs 15C–G )

Pilumnoplax sp. — Clark & O’Shea, 2001: 15. — Martin & Haney 2005: 451, 495.

Intesius richeri Crosnier & Ng, 2004: 266–271 , figs. 2, 3A, 4A–B, 5 [type locality: Norfolk Rise, S of New Caledonia, 23°40’S, 167°42’E, 443–460 m].

Material examined. Rumble III Seamount: NIWA 27549 , 1 female (cl 15.5 mm), 35°44.38–44.35’S, 178°29.85–29.44’E, 220–420 m, hydrothermal vent, TAN0107/005, 19 May 2001 .

Remarks. The single damaged specimen of Intesius richeri represents the first record of the species outside the type locality, and the first record of the genus from New Zealand and a hydrothermal vent site. It agrees well in most respects with the description of the holotype, differing most obviously in having slightly more acute posterior anterolateral spines and a sharper inner carpal spine on the cheliped. Both of these differences probably reflect allometric change, with the New Zealand specimen measuring half the size of the male holotype (cl 15.5 versus 31.8 mm). Moreover, the New Zealand specimen is a juvenile, having rudimentary sternal gonopores, a functional abdominal locking system, and a narrow, male-like abdomen. The telson of the juvenile female is similar to that of the male holotype (length: width ratio 1.51 versus 1.58 and 2.26 versus 2.18, respectively). At 15.5 mm cl, the close resemblance of the juvenile female abdomen to the male form ( Crosnier & Ng 2004: fig. 4B) necessitates examination of the pleopods and gonopores for sex determination.

Distribution. Norfolk Rise, south of New Caledonia, and now from Rumble III seamount, southern Kermadec Ridge, New Zealand; 220–460 m ( Crosnier & Ng 2004; this study).

Figures

FIGURE 15. A, Pycnoplax meridionalis (Rathbun, 1923), male, cl 13.2 mm (NIWA 6643). B, Pycnoplax victoriensis (Rathbun, 1923), female, cl 10.5 mm (NIWA 29349). C–G, Intesius richeri Crosnier & Ng, 2004, female, cl 15.5 mm (NIWA 27549). C, carapace. D, ventral. E, right chela. F, right cheliped carpus. G, right cheliped merus and carpus.