Chromosomes of four Indian marine catfishes (Bagridae, Ariidae: Siluriformes) with a heteromorphic pair in maleMystus gulio

Abstract

Somatic chromosomes of four Indian marine catfishes, Mystus gulio, M. vittatus of Bagridae and Arius nenga, A. serratus of Ariidae, were obtained from the gill epithelial cells and their morphometric analyses were done. M. gulio showed 2n =58, FN = 108 with the chromosome formula 2n = 12m+ 34sm + 4st + 8t in female and 2n = 13m+ 3 3sm + 4st + 8t in male, thus showing the heteromorphic pair of sex chromosomes in male which is rare in fishes and has not been reported earlier on this species. In M. vittatus the 2n =58, FN = 110 with the chromosome formula 2n = lOrn+ 30sm + 12st + 6t were obtained. These data were compared with the available information on these two species and the possible cause of karyotypic variation among them was discussed. The chromosomes of A. nenga and A. serratus were reported for the first time. 2n =54, FN = 108 with 16m+ 36sm + 2st for the former and 2n =56, FN = 112 with 8 m + 24sm + 24st for the latter were determined. A complete revision of the chromosomal studies on the two families were made. The presence of high 2n and FN in all the families of the order Siluriformes and the possible origin of their karyotypes from an ancestral tetraploid form through much chromosomal reorganizations were discussed.

Nucleolar Organizer Regions Polymorphism and Karyological Analysis of Black Lancer, <i>Bagrichthys majusculus</i> (Siluriformes, Bagridae) in Thailand

“…This characteristic is similar to other species in the Bagridae of Thailand (Donsakul 2001, Magtoon and Donsakul 2009, Supiwong et al2013a, b, 2014a. However, some bagrid catfishes in India, including M. gulio and M. tengara have differentiated sex chromosome system as XX/XY and ZZ/ZW, respectively (Rishi 1973, Rishi and Rishi 1981, Choudhury et al 1993, Arai 2011.…”

Comparative study of four Mystus species (Bagridae, Siluriformes) from Thailand: insights into their karyotypic diversity

“…The so far reported 2n for diploid chromosome numbers varies between 50 and 58 chromosomes and for NF from 64 to 110 (Table 1). Intra-specific variations of 2n were reported in M. mysticetus Roberts, 1992 (2n = 50, 52) (Donsakul 2002;Supiwong et al 2014a, b) and M. vittatus (Bloch, 1794) (2n = 50, 54, 58) (Das and Srivastava 1973;Manna and Prasad 1974;Tripathi and Das 1980;Rishi 1981;Sharma and Tripathi 1986;Khuda-Bukhsh and Barat 1987;John et al 1992;Choudhury et al 1993;Ramasamy et al 2010). The cytogenetic characterization of a species could be applied to other fields such as systematics, but also economic interests, as breeding practices of organisms by using chromosome set management (Na-Nakhon et al 1980), strain improvement (Sofy et al 2008) and brood stock selection (Mengampan et al 2004).…”