Saturday, December 19, 2015

[Crustacea • 2015] Taxonomy of The Semiterrestrial Crab Lepidothelphusa cognettii (Nobili, 1903) (Decapoda: Brachyura: Gecarcinucidae), with Descriptions of Five New Species from Sarawak, Malaysia, Borneo


Fig. 13. Live colours of three Lepidothelphusa species from Kuching Division, southwestern Sarawak.
A, B, Lepidothelphusa cognettii (Nobili, 1903), male (12.0 × 10.2 mm) (SBC.C.00382–90), Batu Panggah Trail, Gunung Penrissen, Sarawak; C, D, Lepidothelphusa flavochela, new species, paratype male (8.5 × 7.5 mm) (SBC.C.00392–401), Pagar Besi, Kampung Gumbang, Bau, Sarawak; E, F, Lepidothelphusa limau, new species, paratype male (10.5 × 9.7 mm) (SBC.C.00402–05), Kampung Peros, Bau, Sarawak.
J. Grinang and P. K. L. Ng. 2015. RAFFLES BULLETIN OF ZOOLOGY. 63

Abstract
 The taxonomy of the semiterrestrial gecarcinucid crab Lepidothelphusa cognettii (Nobili, 1903) from Borneo is revised. The identity of Lepidothelphusa cognettii s. str. is clarified and five new speciesLepidothelphusa flavochelaLlimauLloiLpadawan and Lsangon, are described from southwestern Sarawak, Malaysia. The species are characterised by their diagnostic live colours, structures of their carapaces, chelae, male abdomens and male first gonopods. They also occupy geographically discrete ranges, sometimes with different habitats.

Key words: Decapoda, Gecarcinucidae, Lepidothelphusa, taxonomy, revision, mudstone, sandstone, Sarawak


TAXONOMY
Family Gecarcinucidae Rathbun, 1904

Lepidothelphusa Colosi, 1920
Parathelpusa (Lepidothelphusa) Colosi, 1920: 24.
Para-Lepidothelphusa cognetii – Balss, 1937: 174.
Lepidothelphusa – Bott, 1970: 55.

Type species. Potamon (Geotelphusacognettii Nobili, 1903; by original designation; gender of genus feminine.

Lepidothelphusa cognettii (Nobili, 1903) 
Potamon (Geotelphusacognettii Nobili, 1903: 15.
Potamon (Geotelphusacognettii – Rathbun, 1905: 214.
Parathelpusa (Lepidothelphusacognettii – Colosi, 1920: 24 (part).
Para-Lepidothelphusa cognetii (sic) – Balss, 1937: 174 (list).
Lepidothelphusa cognettii – Bott, 1970: 55 (part); Ng & Grinang, 2004: 309 (part).
Lepidothelphusa cognetti (sic) – Ng, 2004: 319 (part); Ng & Yeo, 2007: 108 (part); Ng et al., 2008: 67; Cumberlidge et al., 2009: appendix 1 (part).

Habitat. The habitat of the species is moist rock crevices and leaf litter in shaded springs. The habitat is a primary dipterocarp forest with sandstone substrate and the elevation ranges from 200 m to 1200 m above sea level. The habitat appears to be highly localised. Of the known Lepidothelphusa species, L. cognettii s. str., is the only one known from such high altitudes.


Lepidothelphusa flavochela, new species

Etymology. The name is derived from the Latin “flavo” combined with chela, alluding to the entire yellowish chela. The name is used as a noun in apposition.

Habitat. The habitat is similar to that of L. cognettii s. str. except that it is less than 200 m above sea level.


Lepidothelphusa limau, new species 
Parathelpusa (Lepidothelphusa) cognettii – Colosi, 1920: 24 (part). (not Potamon (Geotelphusa) cognettii Nobili, 1903)
Lepidothelphusa cognettii – Bott, 1970: 55 (part), pl. 7 figs. 69–72, pl. 27 fig. 31; Ng & Grinang, 2004: 309 (part); Ng et al., 2008: 67 (part), 68, fig. 55; Klaus et al., 2009: 513, 521. (not Potamon (Geotelphusa) cognettii Nobili, 1903)
Lepidothelphusa cognetti – Ng, 2004: 319 (part); Ng & Yeo, 2007: 108 (part); Ng et al., 2008: 67; Cumberlidge et al., 2009: appendix 1 (part). (not Potamon (Geotelphusa) cognettii Nobili, 1903)

Etymology. The name is derived from the Iban word “limau” for a plant species popularly called calamansi, Citrofortunella microcarpa (Bunge, 1833), alluding to the yellowish carapace that similar to a ripe fruit of the plant species. The name is used as a noun in apposition.

Habitat. The habitat is relatively flat primary dipterocarp forest and is less than 200 m above sea level. The substrate is moist and consists of sandstone, moist sand with leaf litter.

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.
J. Grinang and P. K. L. Ng. 2015. RAFFLES BULLETIN OF ZOOLOGY. 63

 Lepidothelphusa loi, new species

Etymology. The name is after Michael Lo in recognition of his kind help in helping us search for these interesting animals.

Habitat. The habitat is a gentle slope, with the substrate composed of moist mud and sand, with leaf litter. The site is shaded, has a spring, and is part of a disturbed dipterocarp forest. The base substrate is sandstone, and the site is more than 500 m above sea level.


Lepidothelphusa padawan, new species

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

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.


Lepidothelphusa sangon, new species

Etymology. The name is derived from the Bidayuh word “sangon” for beautiful, alluding to the striking colour of the crab. The name is used as a noun in apposition.

Habitat. The habitat is moist rocks and leaf litter, in partially exposed or shaded, small streams in old primary dipterocarp forests. The substrate is mudstone and the site is less than 200 m above sea level.


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

Jongkar Grinang and Peter K. L. Ng. 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: 564–582.