Assessing sexual dimorphism and systematic with the biometry and scale characteristics of Black pomfret Parastromateus niger (Bloch, 1795)

The knowledge about biometric differences is essential for the description of sexual differentiation of any particular species and also has numerous implementations in fish biology. A total of 100 samples (50 males and 50 females) of Parastromateus niger (Bloch, 1795) commonly called ‘black pomfret’ were gathered from Quetta fish market of Balochistan to observe first time biometrically by calculating the morphometric, meristic and scale characteristics for examining the sexual dimorphism and phylogenetic relationship. The overall results revealed that highly strong and significant correlations (r 70; p 0.05) were observed between morphometric characteristics and total body length (TL), except diameter of eye (ED) for males, females and combined sexes, respectively. Whereas, week and insignificant correlations (r 0.50; p 0.05) were found between meristic characters and TL respectively. Moreover, significant variations (t-test; p 0.05) were found in morphological characteristics between sexes, except ED, snout length (SL) and body depth (DB) and anal fin-rays count (AFC), which reveals insignificant variation (t-test; p 0.05), respectively. However, detail microstructures of scale exhibited no structural variations between males and females; however, could be valuable in systematic study of this species. Thus, it had been concluded that variations in morphometric characteristics could be consider as valuable tools that displays the sexual dimorphism of black pomfret.