Thalamita danae Stimpson, 1858

Published, First, 2009, New records of crabs (Decapoda: Brachyura) from the New Zealand region, including a new species of Rochinia A. Milne-Edwards, 1875 (Majidae), and a revision of the genus Dromia Weber, 1795 (Dromiidae), Zootaxa 2111, pp. 1-66 : 46

Thalamita danae Stimpson, 1858

Fig. 22 a.

Thalamita danae Stimpson, 1858: 37 . — Stephenson & Hudson 1957: 335, figs 2N, 3N, pl. 3, fig. 1, pls 7G, 10D. —

Stephenson & Rees 1967: 70, figs 25a–c, 26a–c. — Davie 1998: 150, colour photo; 2002: 471 (fig.), 478. — Jones & Morgan 2002: 161, 163, 2 colour photos.

Thalamita stimpsoni Milne Edwards, 1861: 362 , pl. 35, fig. 34.— Stephenson & Hudson 1957: 356, figs 2M, 3M, pl. 6, figs 1–3, pls 8R, 9I. — Stephenson & Rees 1967: 98, fig. 36.

Material Examined. Hutchinson Bluff, Raoul I., Kermadec Is: 1 male, 10.8 mm x 7.6 mm, 29°16’S, 177°55’W, 84–114 m, beam trawl, pumice rubble, BS296, 24 Aug. 1972. Due to renovation of the collection building at Te Papa, and transfer of specimens to temporary storage, this specimen was not available for photography. Therefore a photo of Thalamita danae (male CW= 58 mm) published by Stephenson & Hudson (1957: pl. 3 fig. 1) is reproduced here. For comparison a photo of Thalamita macropus (male CW = 24 mm), the other species of this genus recorded from the Kermadec Is, is included ( Fig. 2 b) ( Stephenson & Hudson 1957: pl. 4, fig. 1).

Remarks. The blue mottled swimming crab, Thalamita danae , has strong granular ridges on outer face of cheliped palm. Its habitat includes littoral, sub-littoral depths to 40 m, rocky shores under stones and mussel clumps, on sandy-mud flats and reefs ( Davie, 2002). The specimen reported here came from around 100 m, which is somewhat deeper than recorded in Australia. Takeda & Webber (2006) recorded another species, Thalamita macropus Montgomery, 1931 from Raoul and Chanter Is, Kermadec Is, 31– 135 m.

The main differences between the two species of Thalamita from the Kermadec Is (see Fig. 22a, b) are: T. danae has the first anterolateral tooth without subsidiary tooth (in T. macropus the first anterolateral tooth has a subsidiary basal tooth behind it on the carapace); tips of the 5 anterolateral teeth form a convex shape with the greatest width at the third teeth and last 2 teeth receding (but in T. macropus the teeth on the anterolateral margin are relatively larger and the greatest carapace width is at the last teeth so that the anterolateral margins are divergent and not convex (see Stephenson & Hudson, 1957, pl. 3, fig. 1, pl. 4, fig. 1). The straight frontal carapace margin, with 6 truncate lobes, immediately distinguishes the 2 species of Thalamita from the other portunids, Ovalipes elongatus , Nectocarcinus antarcticus and Liocarcinus corrugatu s.

Distribution. Red Sea, Japan, Indo-Malayan region to Australia, New Caledonia, Marshall Is, Fiji, Samoa, French Polynesia, and now further south to Raoul I., Kermadec Is. Depth range 5– 100 m.