Stock discrimination of Etroplus suratensis (Bloch) along the South Indian coast by morphometric analysis

The objective of the present study was to analyze the morphometric and meristic variations of an estuarine fish, Etroplus suratensis, in five locations along the South Indian coastal region. In total, 651 individuals were collected and 16 morphometric and six meristic counts were taken. The results of univariate (ANOVA) and multivariate (Principal Component Analysis, PCA) analyses showed that the east coast stocks (Machilipatnam, Mudasalodai, Rajakkamangalam) have overlapping morphological characteristics, whereas the west coast stock (Cochin) was distinctly different, but there were no significant differences observed in meristic characters among the five stocks. Therefore, it was presumed that Machilipatnam, Mudasalodai, and Rajakkamangalam were the same stock. The morphometric data discriminated E. suratensis into two stocks, i.e., those of the east and west coasts. However, further molecular-based analysis is very much needed to validate these stocks.