Classification

Prawns are omnivores and essentially scavengers. Some are planktivores and vegetarians. Others feed on aquatic small insects and other animals. The type of food varies according to the developmental stage and species of the prawn. Some females carry fertilized eggs under their abdomen with the pleopods until they hatch, others shed the fertilized eggs in water. Eggs of most species usually hatch as a nauplius larva and pass few larval stages, similar in appearance with the primitive crustacean groups. Bangladesh has very rich source of prawns in the Bay of Bengal, estuaries and freshwater. A total of 56 species is reported, of which 37 are salt water, 12 are brackish water, and 7 are freshwater in habitats. However, some species migrate in between lower and higher saline zones. The prawns are classified under six families, Palaemonidae, Penaeidae, Pandalidae, Alpheidae, Hippolylidae, and Sergestidae. The freshwater species are included in the family Palaemonidae.