Application of scale shape variation in fish systematics - an illustration using six species of the family Nemipteridae (Teleostei: Perciformes)

Abstract

An attempt was made to analyse the variation in the morphology of the tenth lateral line scale of six nemipterid species ( Nemipterus japonicus, Nemipterus bipunctatus, Nemipterus randalli, Parascolopsis aspinosa, Scolopsis vosmeri and Scolopsis bimaculatus ) from Mumbai waters. Outline shape variation of the tenth lateral line scale was subjected to elliptical fourier analysis using 74 fourier descriptors. Images were binarised to generate chain codes using SHAPE 1.3 version. Subsequently, principal component analysis was performed to measure scale shape variation among the six nemipterid species. The study revealed that there is shape variation between the 10 th lateral line scale of the six nemipterid species and the investigation reiterated that scale characteristics can provide useful taxonomic information which could be employed in identification of fish species.