Thryaplax truncata Castro, 2007

Ahyong, Shane T., 2009, First records of Thryaplax Castro, 2007 and Calocarcinus Calman, 1909 (Crustacea: Decapoda: Brachyura) from the Kermadec Islands, New Zealand, Zootaxa 1982, pp. 66-68 : 66

Thryaplax truncata Castro, 2007

( Fig. 1A–C )

Thryaplax truncata Castro, 2007: 683 –685, figs 25, 26 [type locality: Lau submarine ridge, Fiji, 441–506 m].

Material examined. NIWA 41724, 1 female (cl 9.0 mm, cw 12.0 mm), off Curtis Island, Kermadec Islands, 30°17.59’S, 178°25.30’W, 398–412 m, stn K840, 28 Jul 1974.

Remarks. Thyraplax truncata was described from New Caledonia on the basis of five male specimens ( Castro 2007). Thus, the present specimen is the first known female of the species, in addition to representing the first record of the genus and species from New Zealand waters. The Kermadec Islands female agrees closely with the type description, and the female gonopores, having a simple rounded vulvar cover ( Fig. 1B ), accord well with the original generic concept of Thyraplax Castro, 2007 . Of the goneplacids presently known from New Zealand waters, Thyraplax truncata is most similar to species of Pycnoplax Castro, 2007 , but is easily distinguished by the presence of one instead of two anterolateral carapace spines.

Distribution. Fiji, New Caledonia and now from the Kermadec Islands, New Zealand; 398– 506 m.

Figures

FIGURE 1. A – C, Thyraplax truncata Castro, 2007, female (cl 9.0 mm, cw 12.0 mm), NIWA. D, Calocarcinus africanus Calman, 1909, juvenile female (cl 3.8 mm, cw 4.9 mm), NIWA. A, D, dorsal view. B, right female gonopore. C, right maxilliped 3. Scale: A = 3.0 mm, B = 1.5 mm, C = 0.6 mm, D = 0.8 mm.