Morphometrics and Relative Growth of Portunus Segnis (Forskal, 1775) (Crustacea: Portunidae) from Balochistan

Abstract

Shazia Rasheed and Ehsaan Ullah Mengal

Sexual maturity attained by relative growth by different body parts of crab Portunus segnis. Relative growth, short carapace width (SCW compare) to other body parts of male crabs have 48 to 135 mm SCW and female crabs having 38 to 140 mm SCW. Relationship of Total body weight (TBW) and total carapace width (TCW) with SCW was isometric in both sexes. Relationship of carapace length (CL) and abdomen length (AL) to SCW was isometric correlated in females and negative in males. Chelar Propodus width (CPW) with SCW indicated isometric in male and negative female crabs. Size at sexual maturity by Chelar Propodus length (CPL)/ SCW show positive growth in both mature and immature phases of male and female crabs. Pleopod length (PL)/ SCW show positive isometry in both phases in male and puberty moult occurs between 75-80 mm SCW. Relationship of Abdominal width (AW) to SCW was positively correlated in female and negative in male and puberty moult occurs between 68-78 mm SCW in female crabs. In case of female, smallest mature crab had 70 mm SCW while the largest immature crab had 92 mm SCW.

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