Carapace length-weight and carapace width-weight relationship of Portunus pelagicus (Linnaeus, 1758) in Pakistani waters northern Arabian Sea

The carapace length-weight and carapace width-weight relationship of Portunus pelagicus analysis were conducted from Pakistani waters. Total of 897 specimen of both sexes combined were measured in which 478 female and 419 male specimen during January to November 2015. The carapace length-weight of both sexes combined were calculated as W = 0.2888*(2.73) (R-2 = 0.860). However the carapace width-weight of both sexes were as W = 0.1198*(2.79) (R-2 = 0.870). The carapace length-weight of separate sexes (male and female) of P. pelagicus were also calculated as W = 0.967*(2.91) (R-2 = 0.874) and carapace width-weight were as W = 0.8138*(2.95) (R-2 = 0.882). While the carapace width-weight and length-weight of male were calculated as W = 0.967*(2.44) (R-2 = 0.795), W = 0.204*(2.56) (R-2 = 0.809), respectively. The present study shows that the growth of P. pelagicus is isomateric from Pakistani waters.