Morphological, molecular characterization and taxonomic status of Triplophysa marmorata and Triplophysa kashmirensis (Cypriniformes: Nemacheilidae) from Kashmir valley, India.

In India the distribution of genus Triplophysa has been reported only in the upper drainage of the Indus River in Jammu and Kashmir and Lahul and Spiti area of Himachal Pradesh. There is no study on the taxonomic characterization of this genus from Kashmir Himalaya. Therefore the present study was aimed to characterize two important fish species Triplophysa marmorata and T. kashmirensis from Kashmir valley, by using morphometric and molecular tools. It is difficult to discriminate these two species due to the poor quality of original descriptions, and the lack of good reviews. Keeping this in view, a morphometric and molecular study was conducted. Morphometric data were analyzed by using univariate analysis of variance (ANOVA) and multivariate analyses (Principal component analysis) and mtDNA marker Cytochrome oxidase 1 was used for molecular support. Altogether, 22 morphometric characters were used and 15 characters were found significantly variable (P < 0.05). First two components of principal component analysis (PCA) i.e. PC1 and PC2 grouped these two species into separate clusters. The Cytochrome oxidase 1 analysis showed that the mean intraspecific nucleotide divergence (K2P) was 0.001 and interspecific nucleotide divergence was 0.007. Despite having low K2P divergence, these two species got separated into two distinct clades in both Neighbour joining (NJ) and Unweighted Pair Group Method with Arithmetic Mean (UPGMA) tree building methods. But the pattern of clade formation showed that these species were recently radiated from each other and may have the same ancestor. Furthermore, these two species were found closer to Nemacheilidae than to Balitoridae family in the phylogenetic analysis. The molecular divergence between these species was also supported by variance in morphometric data. This work may build the base for the revision of taxonomic identity of these two important fishes of genus Triplophysa. The present investigation formulated that, based on morphological and mtDNA COI sequences analysis, these two taxonomic Triplophysa species should be considered as valid. The results may further assist to enhance the knowledge of the ichthyologists in understanding the ichthyofauna of Kashmir Valley and will help them in planning strategies for conservation and management of these less studied small indigenous species along their natural range of distribution.

Phenotypic differentiation of Barilius bendelisis (Cypriniformes: Cyprinidae) in four rivers from Central Indian Himalaya.

Barilius bendelisis, commonly known as Indian Hill Trout is an upland water fish of South East Asia. It belongs to the family Cyprinidae and dwells in shallow, clear and cold water. In this study, the intraspecific variation of Barilius bendelisis, on the basis of morphometric characters, was investigated. Altogether, 402 specimens were collected from four rivers in the Central Indian Himalaya. A truss network was constructed by interconnecting 12 landmarks to yield 30 distance variables that were extracted from digital images of specimens using tpsDig2 and PAST software. Allometric transformed truss measurements were subjected to univariate analysis of variance, factor analysis and discriminant analysis. All variables exhibited significant differences between the populations. Altogether 88% of the specimens were classified into their original populations (81.98% under a 'leave-one-out' procedure). With factor analysis measurements of the head region, the middle portion and the caudal region had high loadings on the first and second axis. The results indicated that B. bendelisis has significant phenotypic heterogeneity between the geographically isolated regions of Central Indian Himalaya. We hypothesize that the marked interspecific variation in B. bendelisis is the result of local ecological conditions.

Detection of morphometric differentiation in Sattar snowtrout, Schizothorax curvifrons (Cypriniformes: Cyprinidae) from Kashmir Himalaya using a truss network system.

Schizothorax curvifrons is a morphometrically and meristically most variable and economically valuable promising fish food from Kashmir Valley. Since there is a lack of information on stock structure of wild populations on this species, this study was aimed to investigate the intraspecific variation of this important snowtrout. For this, two rivers and one lake in Kashmir Himalaya were sampled from January 2011 to October 2012. Fish body measurements were taken and morphometric characters using the truss network system was constructed. Altogether, 506 fish specimens were collected. Data were subjected to principal component analysis, discriminant function analysis and univariate analysis of variance. The first principal component explained 63.44% of total variation, while second and third components explained 8.34% and 5.31%, respectively. The step-wise discriminant function analysis retained two variables that significantly discriminated the populations. Using these variables 83.4% of the original specimens were classified into their correct groups and 81.1% of the cross-validated (leave one out procedure) specimens were classified into their correct groups. All of the total 31 transformed truss measurements exhibited highly significant (p<0.001) differences between the populations. This represents the first attempt on stock structure of S. curvifrons; therefore, this study will hopefully guide fisheries taxonomists about its current stock structure and would help in its management and conservation programme across Kashmir Himalaya area.

Age and growth in the indian major carp Labeo rohita (Cypriniformes: Cyprinidae) from tropical rivers of Ganga basin, India.

Labeo rohita is a member of the Indian major carp species and originally an inhabitant of the Ganga river network in India. It is among the top ten aquaculture species of the world. Since there is a lack of information on the growth pattern of the wild populations of this species, this study aimed at evaluating the pattern of age and growth, to support the development of effective management plans. A total of 1082 samples of L. rohita were obtained from May 2009 to July 2012 in six drainages of the Ganga basin. Scales of the fish were used to determine the age and growth by analyzing the annual rings growth. Out of six populations, a maximum 8+ age classes were recorded from two rivers (Betwa and Sharda). The back-calculated lengths at 8+ age class ranged from 86.22 cm to 91.66 cm. However, for the rest of rivers up to 7+ age classes were recorded. Among growth parameters, specific rate of length increase (C(l)) and specific rate of weight increase (Cw) showed decreasing trend, and three distinct life stages of L. rohita were recorded based on growth constant data (C(lt)). Analysis of variance (ANOVA) of the back-calculated length data set of six populations indicated a significant difference (p < 0.05). All three populations showed significant variation in length attainment during 1+ and 3+ age groups, while two populations showed significant variation in length attainment during the 2+ and 7+ age classes. Additionally, analysis of age frequency at different length intervals indicated that with increase in age class, number of fish samples was reduced. Since the pattern of life history traits of L. rohita have not been attempted in the recent past; therefore, this study will guide fisheries biologists about the current stock structure of this fish across different spatial scale of the Ganga basin.

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

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.