Taxonomy of Wedgefishes and Guitar fishes in Indian Waters

Interest in elasmobranch biodiversity and taxonomy has grown in recent years (since 2000). Recognizing the importance of accurate species-level taxonomy in biodiversity studies, fisheries management, to understand the composition, now additional efforts have been included in fisheries monitoring. Fisheries scientists are ever more keenly aware of the need for accurate species-level assessments of catches to manage fisheries effectively. Finally, conservation biologists are beginning to recognize how critically important it is to have an accurate understanding of species compositions based on careful taxonomy to prioritize and manage units of biodiversity for conservation (Naylor et al., 2012). The Cartilaginous fishes, consisting of sharks, rays and chimeras belongs to class Chondrichthyes. Today, more than 1,400 species live in the seas and freshwater and estuarine systems of the world. In India, the Chondrichthyes are represented by around 160 species under 67 genera, 28 families and 10 Orders in the Indian region (Kizhakudan et al., 2015). The Bar coding of elasmobranchs is standard for molecular identification of species. Unfortunately, some of the specimens from which tissue samples are derived are misidentified when collected, and because there is no expertly curated reference dataset against which to compare sequences, many are added to GenBank with their original incorrectly assigned identities. Therefore, the combination of molecular and the classical taxonomy (based on morphology) of elasmobranchs is essential to conduct the phylogenetic analysis and avoids incorrect phylogenetic inferences. Globally, 536 shark species, 611 rays and 52 chimeras were assessed by International Union for Conservation of Nature (IUCN) Red List assessment process. Now, 391 (32.6%) species are threatened with extinction. Overfishing is the universal threat affecting all 391 threatened species and is the sole threat for 67.3% of species and interacts with three other threats for the remaining third: loss and degradation of habitat (31.2% of threatened species), climate change (10.2%), and pollution (6.9%). Species are disproportionately threatened in tropical and subtropical coastal waters (Dulvy et al., 2021). Elasmobranchs are characterized by a lifehistory of slow growth, late maturity, and low fecundity, making them extremely susceptible to population decline from overexploitation