Morphometric and meristic variation of congeneric sciaenid fishes Otolithes cuvieri Trewavas, 1974 and Otolithes ruber (Schneider, 1801) from Maharashtra, west coast of India

Abstract

Two closely related species Otolithes cuvieri, Trewavas, 1974 and Otolithes ruber, (Schneider, 1801) have been differentiated based on morphometric and meristic traits. A simple yet useful criterion based on a pair of canine teeth present on the upper and lower jaw as well as position of the mouth is currently used to differentiate two congeneric sciaenid fish species the O. cuvieri and O. ruber. Findings of the present study indicated that simply two morphometric and meristic characters are sufficient to differentiate these two species. MANOVA (Multivariate analysis of variance) and stepwise discriminant function were used to decide the morphometric traits, significant for differentiation of the species of family Sciaenidae. Discriminant function analysis revealed that 98 % of the species were correctly classified based on five morphometric characters namely Pre-pectoral fin length (PPFL), Pre-anal fin length (PAL), Post orbital head length (POHL), Post anal fin length (POAL) and Body depth (BD). The m-transformed morphometric traits were found to be useful tools in generating canonical variables in differentiating the species. The first canonical variables showed altogether 98 % variance. The scatter plots by first three canonical variables have well differentiated the species. Two meristic characters such as the number of gillrakers present on lower limb of first gill arch and figure of arborescent appendages on the swim bladder are important in differentiation of these species.