Complete mitogenome of Lepidopygopsis typus, an evolutionarily-distinct, endangered cyprinid fish from the Western Ghats Biodiversity Hotspot: Phylogenetic relationships and implications for conservation.

The mitogenome of Lepidopygopsis typus, an evolutionarily distinct, endangered, cyprinid fish from the Western Ghats Biodiversity Hotspot, was characterized. Total length of the mitogenome was 16,729 bp, and comprised of 13 protein coding, 22 tRNA and two rRNA genes. Thirteen protein coding genes contributed a total nucleotide length of 11,408 bp, which coded for a total of 3794 amino acids and accounting for 68.2 % of the mitogenome. A maximum likelihood phylogenetic tree based on mitogenomes of members of cyprinid subfamilies Torinae, Schizothoracinae and Schizopygopsinae, recovered L. typus in a well-resolved clade of Torinae with members of the Western Ghats endemic genus Hypselobarbus as sister taxa. Selection analysis suggested that the branch of L. typus and Hypselobarbus spp. was under intensified selection with reference to other members of Torinae. There were 19 codons under diversifying selection in L. typus, which could be the result of positive selection for adapting to high-altitude, upstream tributaries of Periyar River, where the species has a restricted distribution. With respect to Hypselobarbus spp., L. typus was under relaxed selection with about 68 % of codons experiencing neutral evolution. Restricted distribution, low population size and relaxation in selection can likely trigger extinction in L. typus, and therefore urgent conservation and monitoring plans are required to secure the future of this evolutionary distinct, and globally endangered species.

A new diminutive subterranean eel loach species of the genus Pangio (Teleostei: Cobitidae) from Southern India.

A second subterranean species of Pangio is described from an old dug-out well in Kerala, Southern India. The new species, Pangio pathala is unique within the genus in possessing the highest number (27) of caudal vertebrae. Pangio pathala is distinguished from P. bhujia, the only subterranean Pangio species known so far, in having four pectoral-fin rays (vs. three), five anal-fin rays (vs. six), 67 vertebrae (40 abdominal and 27 caudal vertebrae) (vs. 6263), and a raw genetic distance of 8.18.7% in the mitochondrial cytochrome oxidase subunit 1 gene. This paper also provides an additional record of Pangio bhujia from a location 40 km south of the type locality.

Phylogenetic position and relationships of mountain loaches (Teleostei: Balitoridae) of the Western Ghats as revealed by CO1 sequences.

The teleostean family Balitoridae comprises small-sized freshwater fishes adapted to swift-flowing torrential mountain streams in South and South-East Asia. Little is known about their molecular phylogenetics and evolutionary biogeography, and much of the scientific literature that references them is focused on morphological taxonomy. In this paper, we generate CO1 sequences for the endemic balitorid lineages of the Western Ghats (WG) Hotspot in India, particularly for the endemic genera, Bhavania, Ghatsa and Travancoria. Integration of these data into a phylogeny revealed that the endemic WG genera together form a well-supported monophyletic clade that shows, subject to our limited taxon sampling, a sister-group relationship to the Southeast Asian genus Pseudohomaloptera. Three WG endemic species of the genus Balitora, namely B. chipkali, B. jalpalli and B. laticauda, though morphologically distinct, have low genetic divergence and barcode gap, suggestive of recent speciation. Interestingly, a fourth WG endemic, B. mysorensis, formed a clade with two species of Balitora from Eastern-Himalaya and Indo-Burma. We also show that all available CO1 sequences assigned to WG endemic balitorid genera in GenBank are misidentifications, and provide diagnostic characters for the accurate identification of these taxa in the future.

Demographics of Lagocephalus inermis in the Arabian Sea unveils complex conservation challenges.

The first assessment of the demographics of Lagocephalus inermis, a species associated with pufferfish bites and fishing down the food web in the Arabian Sea, south-west coast of India, was performed based on length structured population dynamics of 1601 individuals caught in commercial fisheries. Analysis revealed that the current level of exploitation is 90% of the predicted exploitation producing maximum relative yield per recruit (Emax ), suggesting high levels of exploitation with potential for significant negative consequences for trophic cascades.