Cheliped abnormality and embryonic development of commercially important portunid crab Portunus sanguinolentus (L.)

Abstract

In the present study an attempt was made to study the cheliped abnormalty of commercially important crab, Portunus sanguinolentus. The newly spawned eggs were round and golden yellow in colour. The undeveloped and mass of undifferentiated cells were also found in the berry. The yolk granules were denser. The cleavage and gastrulation were not clear. The diameter of the freshly laid egg was 0.34mm. The multicell eggs were round, deep yellow or yellowish orange in colour. The space between the egg wall and the inner developing embryo was visible. The diameter of the egg was 0.41mm. The eye stage eggs were round and orange in colour. The yolk granules were not denser. The egg diameter was 0.48mm. The pigment stage eggs were brown in colour. The egg diameter was 0.57 mm. The diameter of the egg was 0.64 mm. In prehatching stage the rate of heartbeat was increased and the chromatophores were also found increased throughout the body. The diameter of the egg was 0.73mm. Hence in the present study both the embryonic as well abnormality of cheliped was under taken in to the consideration.