ABSTRACT
Along with the mysteries of their body's shape like snakes, marine eels have fascinated biologists for centuries. Information on the molecular taxonomy of marine eels is scarce from the Southeast Indian region and hence, the present study aimed to barcode marine eels collected from Kasimedu fishing harbor, Chennai, Tamil Nadu. A total of 44 specimens were collected and DNA barcoding was done with a COI marker. The evolutionary history was inferred using the BA method. We observed 17 species, 10 genera, 4 families from the suborder Congroidei of which the genus Ariosoma and Conger were found to be predominant. The species of the family Muraenesocidae and Congridae are highly variable. The average Kimura two-parameter (K2P) distances within species, genera, and families were 3.08%, 6.80%, 13.80%, respectively. Maximum genetic distance (0.307) was observed between the species Muraenesox cinereus and Ariosoma sp.1. BA tree topology revealed distinct clusters in concurrence with the taxonomic status of the species. A deeper split was observed in Uroconger lepturus. We sequenced for the first-time barcode of Sauromuraenesox vorax and a new species Ophichthus chennaiensis is the gap-filling in identifying this taxon in the Indian context. We found a correct match between morphological and genetic identification of the species analyzed, depending on the cluster analysis performed (BINs and ASAP). This demonstrates that the COI gene sequence is suitable for phylogenetic analysis and species identification.
ABSTRACT
Blackbuck (Antilope cervicapra) is a threatened species endemic to the Indian subcontinent. Many populations of blackbuck are found in southern India. Populations of blackbuck are negatively affected in many places for various reasons, such as habitat destruction and poaching. Their range decreased sharply during the 20th century. There is very limited information available on the population dynamics of blackbuck in southern India. For the phylogenetic and genetic diversity analyses of blackbuck populations among different distribution ranges in southern India, we sequenced mt DNA of cytochrome b (Cyt b) for 120, cytochrome c oxidase subunit-1 (COI) for 137 and the control region (CR) for 137 fecal pellets from eleven different locations in southern India. We analyzed the genetic structure of three mitochondrial markers, the CR, Cyt b and the COI region, separately and in a combined dataset. The haplotype diversity and nucleotide diversity of CR were 0.969 and 0.047, respectively, and were higher than those of Cyt b and COI. A Bayesian phylogeny and an MJ network based on the CR and combined dataset (105 sequences) signified several distinct haplotype clusters within blackbuck, whereas no clusters were identified with the Cyt b and COI phylogenetic analyses. The analysis of molecular variance of the combined data set revealed 52.46% genetic variation within the population. Mismatch distribution analysis revealed that blackbuck populations underwent complex changes with analysis of the combined dataset in each population and analysis of each marker separately in the overall population. The results provide evidence that blackbuck in different geographic locations has a distinct population structure due to habitat fragmentation after the formation of the Western and Eastern Ghats.
Subject(s)
Antelopes/genetics , Cytochromes b/genetics , Genetic Variation/genetics , Population Dynamics , Animals , Antelopes/classification , DNA, Mitochondrial/genetics , Ecosystem , Endangered Species , Haplotypes/genetics , India , PhylogenyABSTRACT
In the past two decades, identification of species from noninvasive sampling has turned out to be an important tool for wildlife conservation. In this study a total 93 specimens representing 22 species of ungulates were analyzed from partial sequences of mtDNA COI and Cytb genes. All the species showed unique clades, and sequences divergence within species was between 0.01-3.9% in COI and 0.01-13.7 in Cytb, whereas divergence between species ranged from 2.2 to 29.5% in COI and 2.3 to 28.8% in Cytb. Highest intraspecific divergence was observed within the Ovis aries in COI and Porcula salvania in Cytb. Bayesian (BA) phylogeny analysis of both genes combined distinguishes all the studied species as monophyletic criteria. The Indian rhinoceros (Rhinoceros unicornis) exhibited closer relation to horse (Equus caballus). No barcode gap was observed between species in COI. This study demonstrates that even short fragments of COI and Cytb generated from fecal pellets can efficiently identify the Indian ungulates, thus demonstrating its high potential for use in wildlife conservation activities.
ABSTRACT
A new species of snake eel, Ophichthus chennaiensis sp. nov. (Anguilliformes: Ophichthidae: Ophichthinae), is described on the basis of a specimen collected from dumped fish disposed of by bottom trawlers at Kasimedu fishing harbour, Chennai. Ophichthus chennaiensis sp. nov is distinguished from its congeners by having its dorsal-fin origin one pectoral-fin length behind the pectoral-fin tip, preanal length 2.4 in TL, biserial maxillary, uniserial mandibular teeth, biserial to uniserial vomerine teeth, and its vertebrae (predorsal 19, preanal 53, and total vertebrae 154).
Subject(s)
Eels , Animals , IndiaABSTRACT
The chelonian represents a diverse order of turtles. Little is known about this group from India at molecular level. Cytochrome c oxidase I (COI) sequences of 125 individuals from nine species of freshwater turtles were generated and analyzed. A total of 118 nucleotide positions in COI gene as character-based DNA barcodes for each species were identified. Neighbour-joining (NJ) analyses tree well differentiated freshwater hard shell and softshell turtle. Overall species divergence (K2P) was 13.3%. Analysis of COI sequences from present study, combined with sequences downloaded from NCBI GenBank, revealed new COI haplotypes from Northern region of India.
ABSTRACT
We examined population structure of Labeo dero (Hamilton, 1822) from different riverine locations in India using 10 polymorphic allozyme and eight microsatellite loci. For analysis, 591 different tissue samples were obtained from commercial catches covering a wide geographic range. Allozyme variability (An = 1.28-1.43, Ho = 0.029-0.071) was much lower than for microsatellites (An = 4.625-6.125, Ho = 0.538-0.633). Existence of rare alleles was found at three allozyme (MDH-2, GPI and PGDH) and at two microsatellite loci (R-3 and MFW-15). Deviation from Hardy-Weinberg equilibrium (P < 0.05, after the critical probability levels were adjusted for sequential Bonferroni adjustment) could be detected at three loci (EST-1, -2 and XDH) whereas, after correction for null alleles, two microsatellite loci (MFW-1,-15) deviated from HWE in the river Yamuna. Fst for all the samples combined over all allozyme loci was found to be 0.059 suggesting that 5.9% of the total variation was due to genetic differentiation while microsatellite analysis yielded 0.019 which was concordant to mean Rst (0.02). Hierarchical partition of genetic diversity (AMOVA) showed that greater variability (approx. 95%) was due to within population component than between geographical regions. Based on distribution of genetic differentiation detected by both markers, at least five different genetic stocks of L. dero across its natural distribution could be identified. These results are useful for the evaluation and conservation of L. dero in natural water bodies.
