RESUMEN
DNA barcoding was successfully used for the accurate identification of chondrichthyans in the Indian commercial marine fishery. About 528 specimens of 111 chondrichthyan species and 34 families, collected from the Indian EEZ, were barcoded for a 655 bp region of the mitochondrial gene cytochrome c oxidase subunit 1 (COI). Generally, five specimens per species were barcoded, but numbers ranged from 2 to 13. The average Kimura 2 parameter (K2P) distance separating individuals within species was 0.32%, and the average distance separating species within genera was 6.73%. Ten species were suggested as putative new species requiring formal descriptions. Based on the morphology and molecular support, 11 elasmobranch species were confirmed first records for Indian waters. The present study confirms the ability of DNA barcoding for the accurate identification of sharks, rays, and their products from Indian waters.
Asunto(s)
Código de Barras del ADN Taxonómico/métodos , Complejo IV de Transporte de Electrones/genética , Tiburones/clasificación , Rajidae/clasificación , Animales , ADN Mitocondrial/genética , Evolución Molecular , Proteínas de Peces/genética , Explotaciones Pesqueras , India , Filogenia , Tiburones/genética , Rajidae/genética , Especificidad de la EspecieRESUMEN
Thirty-five individuals of six priacanthid fish species were sampled from different localities along the coast of India covering the Arabian Sea and Bay of Bengal. The partial sequence of 16S rRNA and cytochrome oxidase subunit I (COI) genes were analyzed for species identification and phylogenetic relationship among the Indian priacanthids (Priacanthus hamrur, P. prolixus, P. blochii, P. sagittarius, Cookeolus japonicus, and Pristigenys refulgens). The intraspecies genetic distance ranged from 0.000 to 0.002, while distances varied from 0.008 to 0.157 interspecies based on 16S sequences. Using COI data analysis, the intraspecies genetic distance ranged from 0.000 to 0.005, while interspecies distances varied from 0.009 to 0.108. Several sequences labeled Priacanthus hamrur in GenBank are shown to be P. prolixus. We also observed cryptic speciation in Heteropriacanthus cruentatus. Partial sequences of 16S rRNA and COI genes provided phylogenetic information to distinguish thirteen species of priacanthids, indicating the usefulness of molecular markers in species identification.
Asunto(s)
Genoma Mitocondrial , Perciformes/genética , Animales , Composición de Base , ADN Mitocondrial/aislamiento & purificación , ADN Mitocondrial/metabolismo , Complejo IV de Transporte de Electrones/química , Complejo IV de Transporte de Electrones/clasificación , Complejo IV de Transporte de Electrones/genética , Complejo IV de Transporte de Electrones/metabolismo , India , Perciformes/clasificación , Filogenia , ARN Ribosómico 16S/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
Chlorophthalmus corniger is redescribed on the basis of recently collected specimens. The species is redefined as a species of Chlorophthalmus with the lower jaw terminating in a distinctly projecting horizontal plate with strong, spine-like processes directed forward from the plate's corners; body silvery grey, with numerous minute black spots and traces of broad darker crossbars; base of anterior dorsal fin spines and distal parts of dorsal fins black; adipose fin tiny with numerous black spots; caudal fin black; 3·5 scales above lateral line; three rows of cheek scales; head very large, 34·3-40·1% standard length (LS ); eye large, 29·8-40·8% head length (LH ); pectoral fin long, extending to beyond dorsal fin base, 21·7-26·2% LS . Chlorophthalmus bicornis is a junior synonym of C. corniger based on the examination of the type series of both species. It is confined to the northern half of the Indian Ocean, reliably recorded from Somalia and the Gulf of Aden to southern Java, Indonesia, at depths between 200 and 500 m. A lectotype and three paralectotypes were designated for C. corniger. DNA barcodes for Indian species of Chlorophthalmus were generated.
Asunto(s)
Cipriniformes/clasificación , Aletas de Animales , Animales , Cipriniformes/anatomía & histología , Código de Barras del ADN Taxonómico , Océano Índico , PigmentaciónRESUMEN
Biological data are presented for the poorly known bristly catshark Bythaelurus hispidus based on specimens collected from the by-catch of the commercial deep-sea shrimp trawl fishery operating in the Arabian Sea at depths of 200-500 m off the south-west coast of India. One hundred and sixty-two individuals, which ranged from 120 to 366 mm total length (L(T)), were collected for this study. Size-at-maturity (L50) for females and males was estimated at 252 and 235 mm L(T), respectively. The reproductive mode of B. hispidus was aplacental viviparity, which is the rarest reproductive mode within the Scyliorhinidae and is considered to be the most advanced of the three reproductive modes occurring within this family. Dietary analysis of stomach contents revealed B. hispidus feeds on a variety of prey, primarily fishes.
Asunto(s)
Tiburones/anatomía & histología , Tiburones/embriología , Animales , Femenino , Masculino , Tiburones/fisiologíaRESUMEN
Fishery and biological data are presented for the poorly known bramble shark Echinorhinus brucus (Squaliformes: Echinorhinidae), from the deep waters of the south-eastern Arabian Sea. A total of 5318 individuals from by-catch landings of deep-water bottom set longlines, gillnets and shrimp trawl fisheries operating at depths of 200-1200 m were recorded between January 2008 and December 2011 at the Kochi Fisheries Harbour (Kerala). A total of 431 individuals, from 46 to 318 cm total length (L(T)) and 0·8 to 132 kg total mass (M(T)), were examined to determine biological data for this species. The LT at which 50% were mature (L(T)50) for females and males was estimated at 189 and 187 cm LT. Litter size ranged from 10 to 36 and size at birth was between 42 and 46 cm L(T). Dietary analysis of stomach contents revealed E. brucus feeds on a variety of prey including crustaceans (69% index of relative importance, I(RI)), teleosts (25·8% I(RI)), cephalopods (1·7% I(RI)) and elasmobranchs (0·7% I(RI)). This study provides the first detailed biological data for this species and also highlights the extent of the by-catch fishery for this species in Indian waters.
Asunto(s)
Dieta , Cadena Alimentaria , Tiburones/fisiología , Animales , Femenino , Explotaciones Pesqueras , Contenido Digestivo , India , Masculino , Océanos y Mares , Maduración SexualRESUMEN
Biological data are presented for the pygmy ribbontail catshark Eridacnis radcliffei based on specimens collected from the by-catch of the commercial deep-sea shrimp trawl fishery operating in the Arabian Sea off the south-west coast of India. A total of 549 individuals, from 101 to 257 mm total length (L(T)) and 2·2 to 56 g, were collected. The L(T) at first maturity (L(T50)) of females and males was estimated at 183 and 170 mm, respectively, and analysis of stomach contents revealed that E. radcliffei feeds primarily on crustaceans.