Biological observations on the bristly catshark Bythaelurus hispidus from deep waters off the south-west coast of India

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 200–500m off the south-west coast of India. One hundred and sixtytwo individuals, which ranged from 120 to 366mm total length (LT), were collected for this study. Size-at-maturity (L50) for females and males was estimated at 252 and 235mm LT, 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