Genus Parathelphusa H. Milne Edwards, 1853

Parathelphusa H. Milne Edwards, 1853 (type species Parathelphusa tridentata H. Milne Edwards, 1853, subsequent designation by Rathbun, 1905; gender feminine)

Parathelphusa (Mesotelphusa) Roux, 1915 (type species Telphusa celebensis De Man, 1892, by original designation; gender feminine)

Palawanthelphusa Bott, 1969 (type species Potamon (Parathelphusa) tridentata var. pulcherrima De Man, 1902, by original designation; gender feminine)

Remarks. With the new species described here, Parathelphusa H. Milne Edwards, 1853, currently contains 48 species from southern Thailand, Peninsular Malaysia, Singapore, Sumatra, Brunei, Kalimantan, Java, Sulawesi and Palawan (updated from Ng et al. 2008) (Table 1). Parathelphusa (Mesotelphusa) Roux, 1915 (type species Telphusa celebensis De Man, 1892) is a junior synonym of Parathelphusa, and the only difference is in the form of the anterolateral margin, which is not reliable as a generic character (see Chia & Ng 2006). Bott (1969, 1970) also recognised Palawanthelphusa Bott, 1969 (type species Potamon (Parathelphusa) tridentata var. pulcherrima De Man, 1902) but the only diagnostic character is the form of the G1, which has also shown not to be reliable (see Ng & Goh 1987). It is also a subjective junior synonym of Parathelphusa .

A recent phylogeographic study of Parathelphusa by Klaus et al. (2013) showed that specimens of P. oxygona from Sarawak belonged to a distinct lineage. It also showed that the species diversity in Borneo is higher than what is known at present, with various un-named clades of Parathelphusa . This agrees with unpublished data that indicate that there are at least half a dozen new species from Borneo still awaiting description.

Parathelphusa balabac Ng & Takeda, 1993

Parathelphusa batamensis Ng, 1992

Parathelphusa baweanensis Ng, 1997

Parathelphusa bogorensis Bott, 1970

Parathelphusa cabayugan Freitag & Yeo, 2004

Parathelphusa celebensis (De Man, 1892) [ Thelphusa] = Potamon (Potamonautes) celebense var. immaculata Schenkel, 1902

Parathelphusa ceophallus Ng, 1993

Parathelphusa convexa De Man, 1879

= Thelphusa convexus Herklots, 1861 (nomen nudum) =? Ozius frontalis Targioni Tozzetti, 1872 = Parathelphusa dentipes Heller, 1862

Parathelphusa crocea (Schenkel, 1902) [ Potamon (Potamonautes)]

Parathelphusa ferruginea Chia & Ng, 2006

Parathelphusa linduensis (Roux, 1904) [ Potamon]

Parathelphusa lokaensis (De Man, 1892) [ Telphusa]

Parathelphusa lombokensis Bott, 1970

Parathelphusa maculata De Man, 1879

= Potamon (Parathelphusa) tridentatum var. incertum Lanchester, 1900 = Parathelphusa maculata var. lanchesteri Nobili, 1901

Parathelphusa maindroni (Rathbun, 1902) [ Potamon (Parathelphusa)]

Parathelphusa malaysiana Ng & Takeda, 1992

Parathelphusa manguao Freitag & Yeo, 2004

Parathelphusa mindoro Ng & Takeda, 1993

Parathelphusa modiglianii Nobili, 1903

Parathelphusa nagasakti Ng, 1988

Parathelphusa nana Ng & Takeda, 1993

Parathelphusa nitida Ng, 1986

Parathelphusa nobilii sp. nov.

Parathelphusa obtusa (Bott, 1969) [ Palawanthelphusa]

Parathelphusa ovum Ng, 1995

Parathelphusa oxygona Nobili, 1901

Parathelphusa palawanensis (Bott, 1969) [ Palawanthelphusa]

Parathelphusa pallida (Schenkel, 1902) [ Potamon (Potamonautes)] = Potamon (Potamonautes) celebensis var. annulipes Schenkel, 1902

Parathelphusa pantherina (Schenkel, 1902) [ Potamon (Parathelphusa)]

Parathelphusa pareparensis (De Man, 1892) [ Telphusa]

Parathelphusa parma Ng & Takeda, 1993

Parathelphusa possoensis (Roux, 1904) [ Potamon (Potamonautes)]

Parathelphusa pulcherrima (De Man, 1902) [ Potamon (Parathelphusa)]

Parathelphusa quadrata Ng, 1997

Parathelphusa rasilis Ng & Takeda, 1993

Parathelphusa reticulata Ng, 1990

Parathelphusa sabari Ng, 1986

Parathelphusa saginata Ng & Takeda, 1993

Parathelphusa sarasinorum (Schenkel, 1902) [ Potamon (Potamonautes)]

Parathelphusa sarawakensis Ng, 1986

Parathelphusa shelfordi Nobili, 1901

Parathelphusa sorella Chia & Ng, 2006

Parathelphusa tenuipes (Schenkel, 1902) [ Potamon (Potamonautes)]

Parathelphusa tera Chia & Ng, 1998

Parathelphusa torta Chia & Ng, 1998

Parathelphusa tridentata H. Milne Edwards, 1853 [Direction 36] = Alpheus tridens Weber, 1795 (as 3 dens) (nomen nudum) = Cancer (Thelphusa) tridens De Haan, 1835 (pre-occupied name and nomen nudum) = Thelphusa triodon Herklots, 1861 (nomen nudum)

Parathelphusa undulata Chia & Ng, 1998

Parathelphusa valida Ng & Goh, 1987