Biometric analysis of moustached thryssa Thryssa mystax (Bloch and Schneider, 1801) along the Ratnagiri coast of Maharashtra, India

The moustached thryssa Thryssa mystax (Bloch and Schneider, 1801), is an important bycatch landed by trawl nets and mini purse seines at Ratnagiri in Maharashtra. Morphometric characters and length-weight relationship of the moustached thryssa were studied from 876 specimens comprising of 436 males, 407 females and 33 indeterminates collected from Ratnagiri. The coefficient of correlation of total length against other morphometric characters of T. mystax ranged between 0.3967 (against pre-pelvic length) to 0.9966 (against fork length). All morphometric measures had a high and moderate degree of correlation with total length. The length-weight relationship indicated isometric growth. The coefficient of correlation (r) for the length-weight relationship was estimated at 0.9327, 0.9266, 0.9743 and 0.9379 for the males, females, indeterminants and pooled data, respectively.