Lepidothelphusa padawan, Grinang & Ng, 2015

Grinang, Jongkar & Ng, Peter K. L., 2015, Taxonomy of the semiterrestrial crab Lepidothelphusa cognettii (Nobili, 1903) (Crustacea: Decapoda: Brachyura: Gecarcinucidae), with descriptions of five new species from Sarawak, Malaysia, Borneo, Raffles Bulletin of Zoology 63, pp. 564-582 : 574-576

Lepidothelphusa padawan , new species

( Figs. 9A–I , 10A–E , 14C, D , 15A–F )

Material examined. Holotype: male (13.6 × 12.5 mm) ( ZRC 2015.0608 ), Kampung Sentah, Padawan, Sarawak, coll. J Grinang & HH Tan, 5 November 2013 . Paratypes: 5 males (largest 14.2 × 12.1 mm), 2 females (larger 12.6 × 10.7 mm) (SBC.C.00407–13), location as holotype, coll. J Grinang, 12 January 2014 ; 7 males (largest 10.7 × 10.1 mm), 3 juveniles (SBC.C.00414–23), Sebarau , Kampung Bidak, Padawan, Sarawak, coll. J Grinang & A Alek, 12 January 2014 ; 5 males (largest 9.6 × 8.6 mm), 2 females (larger 9.3 × 8.2 mm) (SBC.C.00424–30), Kampung Petag, Padawan, Sarawak, coll. J Grinang, 14 January 2014 ; 12 males, 3 females ( ZRC 2015.0609 ), Kampung Sentah , Padawan, Sarawak, coll. HH Tan & J Grinang, 5 November 2013 ; 3 males, 3 females ( ZRC 2015.0610 ), Sarawak, from aquarium trade, obtained HH Tan, 4 December 2013 ; 5 males (largest 15.8 × 13.2 mm), 2 females (larger 10.8 × 9.1 mm) (SBC.C.00440–46), Bung Brungu, Padawan, Sarawak, coll. J Grinang, 8 March 2015 .

Diagnosis. Carapace relatively quadrate, surface relatively flat, smooth, anterolateral margins serrated; antero- and posterolateral regions slightly rugose; epibranchial tooth undiscernible; external orbital tooth with outer margin slightly concave, smooth; serrated projection on frontal region distinct; epigastric and postorbital cristae distinct, margins serrated; cervical and H-grooves relatively deep, not confluent ( Fig. 9A, B, D ); ischium of third maxilliped rhomboidal, slightly longer than broad, sulcus undiscernible ( Fig. 9F ); inner margin of merus of chelipeds with large, prominently expanded serrated projection ( Fig. 9G ); carpus of chelipeds smooth, inner angle with broadly triangular tooth ( Fig. 9A ); fingers of adult major male chela strongly gaping ( Fig. 9H, I ); ambulatory legs relatively long, merus of fourth ambulatory legs subequal to length of carapace ( Fig. 9A, E ); male abdomen triangular, somite 6 slightly longer than wide, subequal to length of telson ( Fig. 9C ); G1 cylindrical, sinuous, gently curving outwards; terminal segment distinctly curving outwards ( Fig. 10A, B, D, E ); G2 with relatively long distal segment, about half length of basal segment ( Fig. 10C ).

Colour. In life, the males have dark purple (almost black) ambulatory legs, white chelipeds, and at least three distinctive white-dark purple/black patterns on the carapace: i) carapace white or cream-white (anterior) and dark purple to black (posterior) equally or about equally horizontally ( Figs. 14C, D , 15A, B ); ii) carapace white-dark purple to black broad “V” shaped ( Fig. 15C, D ); and iii) carapace almost or entirely white ( Fig. 15E ). Female crabs are usually a uniform dark brown to purplish-brown to black, with cream-white chelipeds ( Fig. 15F ).

Etymology. The species is named after Padawan, the area where it was collected. The name is used as a noun in apposition.

Remarks. Lepidothelphusa padawan , new species, can be easily distinguished from L. cognettii s. str. and congeners in having a distinctive white-dark purple to black body in life. This contrasting colour pattern is unique among known Lepidothelphusa species. It also differs from other species in having proportionately the widest gape of fingers of the adult major male chela ( Fig. 9H versus Figs. 1H , 3H , 5H , 7H , 11H ). The G1 of L. padawan is diagnostic among congeners in being the most slender and having the terminal segment the most strongly curved ( Fig. 10A, B, D, E ).

Habitat. The habitat is moist rocks and leaf litter, in partially open or shaded forest springs. The area is old primary dipterocarp forest with a mudstone substrate, and elevation is between 100 to 300 m above sea level.

Figures

Fig. 9. Lepidothelphusa padawan, new species, holotype male (13.6 × 12.5 mm) (ZRC 2015.0608), Kampung Sentah, Padawan, Sarawak. A, overall dorsal view of habitus; B, dorsal view of carapace; C, ventral view showing anterior thoracic sternum and male abdomen; D, frontal view of carapace; E, outer view of right fourth ambulatory leg; F, left third maxilliped showing exopod; G, left cheliped showing serrated inner margin of merus; H, outer view of left chela; I, outer view of right chela.

Fig. 10. Lepidothelphusa padawan, new species, holotype male (13.6 × 12.5 mm) (ZRC 2015.0608), Kampung Sentah, Padawan, Sarawak. A, dorsal view of left G1; B, dorsal view of distal part of left G1; C, dorsal view of left G2; D, ventral view of left G1; E, ventral view of distal part of left G1. Scale bars = 0.5 mm.

Fig. 14. Live colours of three Lepidothelphusa species from Kuching Division, southwestern Sarawak. A, B, Lepidothelphusa loi, holotype male (10.3 × 9.6 mm) (ZRC 2015.0607), Gunung Ampungan, Sadong River Basin, Serian, Sarawak; C, D, Lepidothelphusa padawan, new species, paratype male (15.8 × 13.2 mm) (SBC.C.00440–4), Bung Brungu, Padawan, Sarawak; E, F, Lepidothelphusa sangon, new species, paratype male (8.0 × 7.0 mm) (SBC.C.00476), Nawang Waterfall, Bung Bratak, Bau, Sarawak.

Fig. 15. Live colours of Lepidothelphusa padawan, new species, paratypes (ZRC 2015.0609), showing variation. A, male (ca. 11.0 mm carapace width); B, male (ca. 11.0 mm carapace width); C, male (ca. 12.0 mm carapace width); D, male (ca. 12.0 mm carapace width); E, male (ca. 12.0 mm carapace width); F, female (ca. 9.0 mm carapace width). Kampung Sentah, Padawan, Sarawak

Fig. 1. Lepidothelphusa cognettii (Nobili, 1903), male (12.2 × 10.2 mm) (ZRC 2015.0601), Batu Panggah Trail, Gunung Penrissen, Kuching, Sarawak. A, overall dorsal view of habitus; B, dorsal view of carapace; C, ventral view showing anterior thoracic sternum and male abdomen; D, frontal view of carapace; E, outer view of right fourth ambulatory leg; F, left third maxilliped showing exopod; G, left cheliped showing serrated inner margin of merus; H, outer view of left chela; I, outer view of right chela.

Fig. 3. Lepidothelphusa flavochela, new species, holotype male (8.1 × 7.2 mm) (ZRC 2015.0604), Pagar Besi, Kampung Gumbang, Bau, Sarawak. A, overall dorsal view of habitus; B, dorsal view of carapace; C, ventral view showing anterior thoracic sternum and male abdomen; D, frontal view of carapace; E, outer view of right fourth ambulatory leg; F, left third maxilliped showing exopod; G, outer view of right chela; H, outer view of left chela; I, left cheliped showing serrated inner margin of merus.

Fig. 5. Lepidothelphusa limau, new species, holotype male (12.1 × 10.8 mm) (ZRC 2015.0605), Kampung Peros, Krokong, Bau, Sarawak. A, overall dorsal view of habitus; B, dorsal view of carapace; C, ventral view showing anterior thoracic sternum and male abdomen; D, frontal view of carapace; E, outer view of right fourth ambulatory leg; F, left third maxilliped showing exopod; G, left cheliped showing serrated inner margin of merus; H, outer view of left chela; I, outer view of right chela.

Fig. 7. Lepidothelphusa loi, new species, holotype male (10.3 × 9.6 mm) (ZRC 2015.0607), Gunung Ampungan, Sadong River Basin, Serian, Sarawak. A, overall dorsal view of habitus; B, dorsal view of carapace; C, ventral view showing anterior thoracic sternum and male abdomen; D, frontal view of carapace; E, outer view of right fourth ambulatory leg; F, left third maxilliped showing exopod; G, left cheliped showing serrated inner margin of merus; H, outer view of left chela; I, outer view of right chela.

Fig. 11. Lepidothelphusa sangon, new species, holotype male (8.4 × 7.6 mm) (ZRC 2015.0611), Nawang Waterfall, Bung Bratak, Bau, Sarawak. A, overall dorsal view of habitus; B, dorsal view of carapace; C, ventral view showing anterior thoracic sternum and male abdomen; D, frontal view of carapace; E, outer view of right fourth ambulatory leg; F, left third maxilliped showing exopod; G, left cheliped showing serrated inner margin of merus; H, outer view of left chela; I, outer view of right chela.