Terrathelphusa kuchingensis (Nobili, 1901)

Grinang, Jongkar & Ng, Peter K. L., 2015, The identity of the semiterrestrial crab Terrathelphusa kuchingensis (Nobili, 1901) (Crustacea: Decapoda: Brachyura: Gecarcinucidae), with descriptions of four new species from southwestern Sarawak, Borneo, Malaysia, Zootaxa 3946 (3), pp. 331-346 : 332-333

Terrathelphusa kuchingensis (Nobili, 1901) s. str.

( Figs. 1 A–H, 2A–E, 11A, B)

Potamon (Geothelphusa) kuchingensis Nobili, 1901: 5 ; Rathbun 1905: 217.

Parathelphusa (Liothelphusa) kuchingensis— Colosi 1920: 27.

Thelphusula melanippe buergeri— Bott 1970: 61 (part) (not Potamon (Geothelphusa) bürgeri De Man, 1899 ).

Terrathelphusa kuchingensis— Ng 1989: 127, pl. 4, fig. 3, colour pl. 2B; Ng 1995: 195; Ng & Grinang 2004: 314, fig. 7; Ng 2004: 327; Ng & Yeo 2007: 111; Ng et al. 2008: 73; Cumberlidge et al. 2009: appendix 1; Grinang 2013: 6, pl. 3.

Material examined. Holotype: female (25.0 × 19.5 mm) ( MUT), Kuching, coll. R. Shelford, December 1891. Paratype: 1 male (22.5 × 18.4 mm), 3 females (largest 34.6 × 26.0 mm) (SM Cru 1986.62-65), Kuching, Sarawak, as Geothelphusa kuchingense by G. Nobili, same data as holotype; 1 male (36.0 × 26.4 mm) ( ZRC 2015.0001), farming plots, foothill of Gunung Temurang, Kuching, Sarawak, 1O12’34.4”N 110O16’10.1”E, 63 m asl, Padawan- Penrissen limestone formation, coll. J. Grinang et al., 16 August 2009.

Diagnosis. Carapace evenly oval transversely, longitudinally, surface convex, conspicuously smooth; epigastric cristae separated by deep epigastric groove; H-groove deep, almost confluent with cervical grooves; epibranchial tooth indistinct but can be separated from external orbital angle by notch, anterolateral, frontal regions appearing compressed; supraorbital margin almost parallel with frontal margin; epistome median lobe pointed to bifurcated ( Fig. 1 A–C; Ng, 1989: pls. 4A–C). Male abdomen with elongated somite 6, lateral margins gently concave ( Fig. 1 D). Ischium of third maxilliped rectangular, about 1.8 times maximum width ( Fig. 1 E). Ambulatory legs smooth, long, about 3.9 times width ( Fig. 1 F; Ng, 1989: pl. 4A). Cheliped carpus rugose, without granules ( Fig. 1 G, H), inner angle with acutely triangular tooth ( Fig. 1 A); gap between major chela conspicuously wide ( Fig. 1 H). G1 terminal segment cone-shaped, tapered, gently curving outwards, subequal to half-length of subterminal segment ( Fig. 2 A, B, D, E; Ng 1989: Fig. 3 B, C).

Life colour. Carapace is dark purple with orange to white legs and chelipeds ( Fig. 11 A, B).

Habitat. Foothills of limestone outcrops and adjacent farming plots; in shaded and moist soil. Individuals live in burrows about 1 m deep.

Remarks. The taxonomic problems associated with T. kuchingensis , mostly on the absence of fresh specimens and their precise provenance, have been discussed at length by Ng (1989) and Ng & Grinang (2004). Nobili (1901) only recorded that the holotype specimen was passed to him by Robert Shelford, curator of zoology in the Sarawak Museum, who obtained it from Kuching in Sarawak. Recent collections in the Kuching region have provided further knowledge on the taxonomy and precise distribution of the species. The recent male specimen agrees very well with description of the species by Ng (1989) and the SM specimens collected at around the same time as the type. It was collected from Gunung Temurang in Padawan-Penrissen limestone formation area. The limestone hill is located about 5 km from Pangkalan Ampat, a site where Shelford stayed during his expedition to Gunung Penrissen (Shelford 1900), during which he and/or his field assistants probably collected the holotype female specimen (see also Bott 1970; Ng 1989).

Ng (1989) had identified a red crab photographed by Gerald Cubitt in Bako National Park as possibly being T. kuchingensis , but recent collections have showed all known Terrathelphusa species from the Kuching region do not have this appearance or colour (see below). The Bako crab is actually very similar to Thelphusula cristicervix (Ng & Grinang, 2004) from Sama Jaya Nature Reserve in Kuching (see Grinang & Ng 2014). In light of the present revision, most of the specimens that had been identified as T. kuchingensis by Ng & Grinang (2004) are here referred to another taxon, T. kundong n. sp.

Figures

FIGURE 1. Terrathelphusa kuchingensis (Nobili, 1901), male (36.0 × 26.4 mm) (ZRC 2015.0001), Gunung Temurang, Kuching, Sarawak, Padawan-Penrissen limestone formation. A, overall dorsal view; B, dorsal view of carapace; C, frontal view of carapace; D, ventral view showing anterior thoracic sternum and male abdomen; E, left third maxilliped; F, outer view of right fourth ambulatory leg; G, outer view of right chela; H, outer view of left chela.

FIGURE 2. Terrathelphusa kuchingensis (Nobili, 1901), male (36.0 × 26.4 mm) (ZRC 2015.0001), Gunung Temurang, Kuching, Sarawak, Padawan-Penrissen limestone formation. A, ventral view of left G 1; B, ventral view of distal part of left G 1; C, dorsal view of left G 2; D, dorsal view of G 1; E, dorsal view of distal part of left G 1. Scales: A, C, D = 1 mm; B, E = 0.5 mm.

FIGURE 3. Terrathelphusa aglaia n. sp., holotype male (35.9 × 26.6 mm) (ZRC 2015.0002), sandstone outcrop, Gunung Penrissen, Kuching, Sarawak. A, overall dorsal view; B, dorsal view of carapace; C, frontal view of carapace; D, ventral view showing anterior thoracic sternum and male abdomen; E, left third maxilliped; F, outer view of right fourth ambulatory leg; G, outer view of right chela; H, outer view of left chela.

FIGURE 11. Life colour of five species of Terrathelphusa from Kuching Division, Sarawak. A, B, Terrathelphusa kuchingensis (Nobili, 1901), male (36.0 × 26.4 mm) (ZRC 2015.0001), shortly after collection, Gunung Temurang; C, D, Terrathelphusa aglaia n. sp., holotype male (35.9 × 26.6 mm) (ZRC 2015.0002), Gunung Penrissen; E, F, Terrathelphusa cerina n. sp., female (24.2 × 20.1 mm), captured-marked-released, Gunung Singai; G, H, Terrathelphusa kundong n. sp., female (30.8 × 23.0 mm) (SBC. C. 00364 - 65), Gunung Serambu; I, J, Terrathelphusa mas n. sp., holotype male (35.5 × 26.4 mm) (ZRC 2015.0005), Gunung Penrissen.