Eco. Env. & Cons. 26 (1) : 2020; pp. (177-179) Copyright@ EM International ISSN 0971–765X *Corresponding author’s email: angsumanchanda@yahoo.in Taxonomic consideration and distributional range extension of Osteochilichthys thomassi up to Subarnarekha basin of West Bengal, India Arun Jana, Godhuli Sit and Angsuman Chanda* PG Department of Zoology, Raja N. L. Khan Women’s College (Autonomous), Midnapur, Paschim Medinipur, West Bengal, India (Received 7 August, 2019; accepted 29 September, 2019) ABSTRACT Osteochilichthys thomassi is a small endemic freshwater fish of Western Ghats region found in Krishna and Kaveri river of south India. Currently the species has been reported by Ali and his co-workers from Tami Nadu, Kerala, Karnataka and Andhra Pradesh. Present work reveals that the species is available in the Subarnarekha basin of West Bengal (Silda under Binpur-II). Therefore, O. thomassi is a widely distributed species, supporting Dahanukar observation and extends its distribution up to south-eastern part of India Key words: Osteochilichthys thomassi, Extend, Distribution, West Bengal. Introduction Osteochilichthys thomassi is a small endemic freshwa- ter fish of Western Ghats region (Talwar and Jhingran, 1991) originally described by Day (1877) as Scaphiodon thomassi. Hora (1942) revised the ge- neric status of the fish species and considered it as Osteochilus (Osteochilichthys) thomassi. Pethiyagoda and Kottelat (1994) and Jayaram (2010) considered the species as Osteochilichthys thomassi. Regarding the distribution of the species, Ali et al. (2013) re- ported it from Tami Nadu, Kerala, Karnataka and Andhra Pradesh. Therefore, the species is no longer endemic to the Western Ghats. Present study re- veals the existence of the species in the Subarnarekha basin of West Bengal but in very few in numbers. Present report is the extension of distri- butional range for the species up to South-Western part of Bengal as well as addition in faunal richness of West Bengal Biodiversity. Methods The specimens were collected from different rivers, ponds, bills, markets of different blocks of Paschim Medinipur and Jhargram district, West Bengal. Af- ter collection, the specimens were immediately pre- served by 4% formaldehyde and brought to labora- tory of the department of Zoology (UG & PG) of Raja N. L. Khan Women’s College (Autonomous). Finally specimens were washed and preserved 4-6% formaldehyde in a labelling container. The speci- mens was studied morphologically such as size, colour, colour band, fin number, fin shape, fin rays, scale number etc. All measurement of fish was made in matric system followed by Tawar Jihngran, 1991; Jayaram, K.C, 1999, Jayagram, K. C. 2010 & www. Fishbase.org. Distribution of this species had recorded. Systematics Osteochilichthys thomassi (Day, 1877)