The taxonomy of three morphologically related and endemic genera of the northern Western Ghats (Ghatiana Pati & Sharma, 2014, Gubernatoriana Bott, 1970, and Inglethelphusa Bott, 1970) is re-assessed to accommodate several new taxa. We describe a new genus, Sahyadriana gen. nov. and its five new species [S. billyarjani sp. nov., S. pachyphallus sp. nov., S. sahyadriensis sp. nov. (type species), S. tenuiphallus sp. nov., and S. woodmasoni sp. nov.]. Additionally, three new species each of Ghatiana (Gh. botti sp. nov., Gh. pulchra sp. nov., and Gh. rathbunae sp. nov.) and Gubernatoriana (Gu. longipes sp. nov., Gu. marleshwarensis sp. nov., and Gu. wallacei sp. nov.) are described. Five species previously in Gubernatoriana are now transferred to Sahyadriana gen. nov., viz. S. alcocki (Pati in Pati, Thackeray & Khaire, 2016) comb. nov., S. pilosipes (Alcock, 1909) comb. nov., S. thackerayi (Pati in Pati, Thackeray & Khaire, 2016) comb. nov., S. triangulus (Pati & Sharma, 2014) comb. nov., and S. waghi (Pati in Pati, Thackeray & Khaire, 2016) comb. nov. Gubernatoriana basalticola Klaus, Fernandez & Yeo, 2014, is transferred to Ghatiana. Inglethelphusa is still proved to be monotypic. Consequently, Ghatiana now contains eight species, three of which are new; Gubernatoriana, four species, including three new species; Inglethelphusa, one species; and Sahyadriana gen. nov., ten species, including five new species. Sahyadriana pilosipes is rediscovered more than a century after its description. All these genera can be separated from other Indian gecarcinucid crabs by the absence of a flagellum on the exopod of the third maxilliped and a very short G2. The relevant identification keys are revised. Currently, 120 species of freshwater crabs under 35 genera and two families are found in India. Kerala is the most species-rich (35 species) state in India followed by Maharashtra (29 species) and Assam (21 species). The Western Ghats of India now includes 17 genera and 58 species of gecarcinucid crabs. A checklist and distribution of Indian freshwater crabs is provided.

The potamid genus AcanthopotamonKemp, 1918 is known from three species, A. fungosum (Alcock, 1909), A. martensi (Wood-Mason, 1875) (type species), and A. panningi (Bott, 1966), and is found in Bangladesh, India, Nepal, and Pakistan. Within this range, the genus is found in the ‘Ganges Delta and Plain,’ ‘Lower and Middle Indus,’ and ‘Namuda-Tapi’ freshwater ecoregions. Here we describe a fourth species, A. horaisp. nov., from northeastern India (Arunachal Pradesh, Assam, and Mizoram) in the ‘Middle Brahmaputra’ and ‘Ganges Delta and Plain’ freshwater ecoregions. The new species possesses a unique suite of external and gonopod morphological characters, with the slender and narrowly conical terminal segment of the first male gonopod being particularly diagnostic. A key to the species of Acanthopotamon is provided.

Two new species of freshwater crabs of the potamid genus Potamiscus Alcock, 1909 are described from Nagaland State of northeastern India. Potamiscus chizami sp. nov. and Potamiscus mima sp. nov. most resemble two Indian congeners [Potamiscus palelensis Mitra and Waikhom, 2019 and Potamiscus tumidulus (Alcock, 1909)] and a species from Myanmar (Potamiscus whitteni Ng, Hla Htoo and Win Mar, 2020) due to the similar terminal segment of the male first gonopod. Both new species can be distinguished from Po. palelensis by their stouter ambulatory legs, from Po. tumidulus by their more-slender male first gonopod, and from Po. whitteni by their strongly concave lateral margins of the male telson and the straight tip of the male first gonopod. Characters of the carapace, male pleon, male gonopods, and female vulvae are employed to differentiate Po. chizami sp. nov. from Po. mima sp. nov.

A new genus of freshwater crab, Ghatiana, with two new species, Ghatiana aurantiaca and Ghatiana hyacintha, and a new species of Gubernatoriana Bott, 1970, are described from the Western Ghat Mountains in Maharashtra State, India. Ghatiana is most similar to Gubernatoriana by its wide, highly arched carapace and by the shape of the male abdomen. Nevertheless, the new genus can be distinguished from Gubernatoriana by the broadness of carapace, length of male abdomen, shape of sixth abdominal somite, length of telson and length of G1 terminal article. Ghatiana aurantiaca sp. nov. and G. hyacintha sp. nov. are distinguished by differences in body colour, carapace width, and G1 morphology, whereas Gubernatoriana triangulus sp. nov. is distinguished from two other known species [Gubernatoriana gubernatoris (Alcock, 1909) and Gubernatoriana pilosipes (Alcock, 1909)] by its triangular G1 subterminal segment and by its carapace morphology. Keys to the species of both the genera are provided. http://www.zoobank.org/urn:lsid:zoobank.org:pub:36BAA1EA-DC15-4B06-BA09-7BD26C63FF54

The identity of the potamid freshwater crab, Indochinamon manipurense (Alcock, 1909) from the state of Manipur in northeast India, is clarified based on an examination of the type specimens. The species is redescribed and a lectotype designated. Specimens from the same region previously referred to this species were compared to the types of I. manipurense and shown to belong to a new species of Potamiscus Alcock, 1909, instead. The new species, Potamiscus takedai sp. nov., can easily be separated from I. manipurense by the characters in the carapace, third maxilliped, male pleon, male gonopods, and female vulvae. Potamiscus takedai sp. nov. can be differentiated from congeners mainly by the strongly bent terminal segment of the male first gonopod and a relatively shorter distal segment of the male second gonopod.