Journal of Applied and Natural Science 5 (2): 503-509 (2013)
Fishes of the genus Olyra McClelland (Teleostei: Bagridae) from Indo-Bhutan hill streams of Assam, India
Sewali Pathak1*, Mrigendra M. Goswami2 and Nripendra Nath Sharma3
1Department of Zoology, Bijni College, Bijni, Chirang-783390 (Assam), INDIA
2Department of Zoology, Gauhati University, Guwahati-781014 (Assam), INDIA
3Department of Zoology (Ex-HOD), Bajali College, Pathsala, Pin-781346, Barpeta (Assam), INDIA
*Corresponding author. E-mail: firstname.lastname@example.org
Abstract : The type specimens described in this communication are collected from two hill streams, Kanamakra and Langkhar flowing from the Bhutan foothills of the Himalaya through Amguri and Amteka respectively in the Indo-Bhutan border of Chirang district (26015’ 0” - 2700’ 0” N and 90030’ 0” - 90045’ 0” E) of Assam. The occurrence of three catfishes species of the genus Olyra, of which Olyra horae is recorded as a new report from the type locality of Assam. The taxonomic variables of O. horae are compared with other two species namely, O. kempi and O. longicaudata. The O. horae is distinguished from the other two congeners in having the caudal fin forked but not high, upper lobe slightly elongated with 10 rays and lower lobe with 9 rays. It can also be distinguished in having the higher range of the caudal peduncle length (16.9 - 20.0 % SL), pre-anal length (60.1 - 71.4 % SL), head width (81.3 - 81.6 % HL) and the lower range of snout length (21.7 - 24.3 % HL), outer mandibular barbel length (55.7 - 57.3 % HL) in comparison to the other two congeners.
Keywords : Brahmaputra drainage, Indo-Bhutan streams, Olyra catfish species, Siluriformes.