Length weight relationships and regressions between otolith size (length, width, size and aspect ratio) and fish length and weight of the bathy pelagic fish Psenopsis cyanea collected from Arabian Sea, west coast of India is provided. Statistical analysis indicate proportionately high females in the population compared to males. The length weight relationship for the fish showed an isometric growth pattern for male (b= 3.4574, R2>0.89) and positively allometric growth pattern for female (b= 3.7782, R2>0.915). Growth pattern among sexes was found to be statistically significant (ANCOVA). No significant difference was noticed between the size of left and right otoliths observed by t-test. The length weight relationship of the otolith of both male and female showed an isometric growth pattern (R2>0.97). The data fitted well to the regression model for both otolith length (OL), otolith width (OW) and otolith weight (OWe) to standard length (SL) (R2>0.89). The data indicated that aspect ratio is not well correlated with standard length (SL) (R2<0.45). The study indicated that these relationships can be used as a helpful tool in predicting fish length and weight from the otoliths and in calculating the prey biomass. These relationships can be used to build the body size and prey biomass during feeding studies and palaeontology. 

Psenopsis cyanea, length-weight relationship, otolith, Arabian Sea