Karyotype of a New Loach Schistura obliquofascia and a Mahseer Puntius chelynoides from Kumaun Hills of Himalaya

Abstract

The karyotypical analysis of two fish species, Schistura obliquofascia and Puntius chelynoides, from the Kumaun Himalayan Rivers was carried out to ascertain the taxonomic position of the species. The diploid chromosome number in S. obliquofascia was ascertained to be 2n = 50 with a karyotype of 2n = 20 metacentric (m), 20 submetacentric (sm), 6 subtelocentric (st) and 4 telocentric (t) chromosomes, and a fundamental arm number (FN) of 90, where as in P. chelynoides, the diploid chromosome number was 100 with a karyotypic formula of 2n = 26m+16sm+18st+40t with a fundamental arm number (FN) of 142. No sex chromosome pair was identified in the form of a heteromorphic pair in either of the species. The relationship within closely related species for both the genus was also discussed using this chromosomal data.