Karyotypic Diversity of Some Freshwater Fish Species in Rural Ponds of Orissa, India

Abstract

Study on chromosomes of fish has become a priority area of research in recent years. Chromosome analysis can be useful for addressing a variety of evolutionary and genetic questions about fishes. The global fish fauna consists of about 28,900 species of fishes of which 2,200 species are cytogenetically studied. India's contribution so far was around 220 species. Fish chromosome studies of freshwater fishes are further sporadic in Orissa. Therefore, the present study is proposed for a systematic cytogenetic investigation of some freshwater fishes of Orissa.
Karyotypic study of 5 species namely Labeo fimbriatus (Fam. Cyprinidae), Puntius sophore (Fam. Cyprinidae), Osteobrama cotio cotio (Fam. Cyprinidae), Chanda nama (Fam. Chandidae), and, Xenentodon cancila (Fam. Benonidae) from rural ponds of Bhubaneswar, India, was carried out. The diploid chromosome number in Labeo fimbriatus was 50 with a chromosomal formula of 10m+10sm+30T (FN=70), Puntius sophore 2n=48, 2m+46T (FN=50), Osteobrama cotio cotio 2n=54, 10m+8sm+8st+28T (FN=72), Chanda nama 2n=50, 8m+6sm+10st+26T (FN=64) and Xenentodon cancila, 2n=48 with chromosomal formula of 22m+10sm+6st+10T (FN=80). The evolutionary significance of these karyotypes of 5 species has been discussed.