Javaid Iqbal Mir

PATTERN OF MORPHOMETRIC DIFFERENTIATION AMONG THREE POPULATIONS OF SNOWTROUT, SCHIZOTHORAX PLAGIOSTOMUS (ACTINOPTERYGII: CYPRINIFORMES: CYPRINIDAE), FROM KASHMIR HIMALAYA USING A TRUSS NETWORK SYSTEM

Background. The fishes of the genus Schizothorax , commonly known as snowtrouts, are a group of species that are difficult to distinguish based on external morphological characters. One of them, Schizothorax plagiostomus Heckel, 1838, is a commercially important freshwater fish with wide distribution along the Himalayan foothills. However, recent observations have indicated drastic declines and change in the stock structure of this species in many areas of its range due to the introduction of exotics, water impoundments (dams), and overfishing. Therefore, this study was intended to verify the variation in stock structure of this species in Kashmir Himalaya by using morphological characters generated by truss network analysis . Materials and methods. A total number of 189 specimens of S. plagiostomus were collected from three differ - ent water bodies of Kashmir Himalaya. A truss network was constructed by interconnecting 12 landmarks to form a total of 30 distance variables extracted from digital images of samples using tpsDig2 and PAST software plat - forms. The transformed truss measurements were subjected to principal component analysis, discriminant func - tion analysis, and univariate analysis of variance for identification of different parameters responsible for popu - lation discrimination among these water bodies . Results. The principal component analysis generated nine components explaining 86.4% of total variance in samples. The step-wise discriminant function analysis retained two variables that significantly discriminated the populations. These two variables showed significant variation in head region, body depth, and caudal peduncle region of fish. Using these variables, 98.4% of the original groups were classified into their correct samples and 93.7% of cross-validated groups omitting one procedure were classified into their correct samples . Conclusion. This study has provided basic information about morphometric variation of S. plagiostomus , which could be indicative of the underlying stock structure of the species. A clear phenotypic divergence among S. pla - giostomus samples revealed the existence of three differentiated groups viz., the Dal Lake population, the Jhelum River, and the Lidder River populations in Kashmir Himalaya. This study should be considered in fisheries man - agement and commercial exploitation of this species and any stock enhancement program .

Molecular characterization of rainbow trout, Oncorhynchus mykiss (Walbaum, 1792) stocks in India

In India, rainbow trout was introduced by British more than 100 years ago (Agarwal 2006) for recreational purposes. The fish is being cultured in both government and private farms of different coldwater states of India, mainly in Jammu and Kashmir, Himachal Pradesh, Sikkim, Arunachal Pradesh and Uttarakhand, and also in Nilgiri hills of south India for breeding and rearing purposes. In recent past, growth and production rate of this fish in various farms has been reduced. Microsatellite markers in combination with recent statistical approaches represent a useful tool for genetic characterization which ultimately supports the management of cultured stocks. These markers have been successfully used to evaluate the wild and farm stocks of rainbow trout in western Australia (Ward et al. 2003); resident and anadromus forms in the Walla Walla river (Narum et al. 2004); domesticated strains of rainbow trout in USA (Silverstein et al. 2004); strains in northern and eastern Europe (Gross et al. 2007) and three groups of different origin in north of Iran (Yousefian et al. 2012). Hence, the present study was carried out to assess the genetic variability in different stocks of rainbow trout in India using microsatellite markers.

Morphometric variation and molecular characterization of snow trout species from Kashmir valley, India

Abstract There is a significant taxonomic ambiguity among snow trout species due to their morphometric similarities. In view of this, a morphometric and molecular study was conducted on five different species of genus Schizothorax that have been reported from Kashmir valley. Morphometric data analyzed using multivariate statistics (Principal component analysis and cluster analysis) indicated the significant grouping of species to individual clusters. Mitochondrial DNA cytochrome oxidase I (COI) gene analysis revealed 0.2%–4.5% genetic divergence among the five species. This study confirms that utility of cytochrome oxidase I in species delineation along with morphometric data. Phylogenetic tree obtained using Neighbor-Joining method revealed that all the five species represented distinct species group. The Schizothorax genus formed two distinct clades; one containing S. niger, S. curvifrons and S. plagiostomus, while other clade containing S. esocinus and S. labiatus. This phlogeny trend was also supported by cluster analysis of morphometric characters. The phylogenetic analysis with other published COI sequences revealed distinct nature of these five species. The study may aid in the taxonomic identification of snow trout species in India. This may further increase the knowledge of the ichthyologists in planning conservation and management strategies for these important fish species along with their natural habitat.