Parathelphusa pulcherrima (De Man, 1902 )

Ng, Peter K. L., , Martyn E. Y. Low, Clark, & Paul F., 2022, Historical notes on various collectors of unidentified freshwater crabs (Crustacea: Decapoda: Brachyura) from the Malay Peninsula and Borneo, with descriptions of two new species of Isolapotamon Bott, 1968 Potamidae), Raffles Bulletin of Zoology 70, pp. 550-571 : 564

Parathelphusa pulcherrima (De Man, 1902)

Potamon (Parathelphusa) tridentatum var. pulcherrima De Man, 1902: 270 , 550, pl. 20, fig. 15.

Material examined. Borneo. 1 male ( NHM 1893.3.26.21), Marabah , Kinabatangan Area, North Borneo, coll. A. Everett, December 1892 ; 1 male, 1 ovig. female ( NHM 1895.7.2.28–29), Baram , coll. C. Hose, February, March 1895 (respectively) ; 3 females ( NHM 1895.7.2.30–32), Baram , coll. C. Hose, February 1895 ; 1 female, Baram , Borneo ( NHM 1895.7.2.35), coll. C. Hose, February 1895 ; 1 male, 1 female ( NHM 2022.156 ), Baram River , coll. C. Hose.

Remarks. This distinctive and somewhat variable species was characterised by Bott (1970) and is known from the Baram River drainage and adjacent areas where it was described (De Man, 1902; Holthuis, 1979). Ng & Goh (1987: 317) discussed the taxonomy of P. pulcherrima at length, and noted that P. shelfordi ( Nobili, 1901) , described from Limbang, Brunei is likely to be a senior synonym. For the moment, they are treated as separate taxa (cf. Ng et al., 2008) as the margin of the external orbital angle of P. shelfordi is serrate (cf. Nobili, 1901) but is entire and smooth in P. pulcherrima , and there is also genetic data to suggest they are separate taxa ( Klaus et al., 2013).