In a recent paper published by the California Academy of Sciences (Vol. 50, No. 14, pp. 315-345, September 1998), Tyson Roberts and Carl Ferraris reviewed the sisorid genera Gagata and Nangra and erected the new genus Gangra for Gangra viridescens. The authors' new revision leaves the above genera with the following species:
Gagata cenia
Gagata
Gagata cenia (Hamilton, 1822) from the Ganges basin, Indus River system and Mahanadi River.
Gagata dolichonema He, 1996 known only from the upper reaches of the Salween basin.
Gagata gagata (Hamilton, 1822) known only from the Ganges basin of India and Bangladesh.
Gagata gasawyuh Roberts & Ferraris, 1998 from the Irrawaddy, Salween, and Tenasserim basins of Myanmar (Burma).
Gagata itchkeea (Sykes, 1839) restricted to Peninsular India: Narmada, Krishna, and Cauvery basins.
Gagata melanopterus Roberts & Ferraris, 1998 known from the Irrawaddy, Rangoon, Sittang, and lower Salween basins of Myanmar.
Gagata sexualis Tilak, 1970 known only from the Ganges basin, including the Brahmaputra River.
Gagata youssoufi Ataur Rahman, 1976 known only from the Ganges basin.
Gangra viridescens
Gangra
Gangra viridescens (Hamilton, 1822) found throughout the lowland parts of the Ganges-Brahmaputra system.
Nangra
Nangra bucculenta Roberts & Ferraris, 1998 known only from the Tangail District of central Bangladesh.
Nangra carcharhinoides Roberts & Ferraris, 1998 known only from the Ganges near Patna.
Nangra nangra (Hamilton, 1822) from the Gangetic basin and Indus River.
Nangra ornata Roberts and Ferraris, 1998 known only from the type locality in the Surma or Meghna watershed in NE Bangladesh.
Nangra robusta Mizra & Awan, 1973 reported from the Indus River in Pakistan where it is rare.
Reference: Roberts T. R. & C. J. Ferraris. 1998. Review of south Asian catfish genera Gagata and Nangra, with descriptions of a new genus and five new species. Proc. Cal. Acad. Sci. Vol. 50, No. 14: 315-354, 19 figs., 3 tables.