SOME ANATOMICAL STUDIES ON THORACIC LEGS OF THE EGYPTIAN RED SWAMP CRAYFISH

El-Gendy, E.M.,1 Eissa, A.A.,2 El-Bably, S. H.1 and Sary, R.G.1

Abstract

This study was conducted on the red swamp crayfish (procambarus clarckii) as one of crustacean covered by a hard chitenious exoskeleton which divided the body into, the cephalothorax and the abdomen. The cephalothorax consisted of the cephalic region and the thoracic region. The part of the exoskeleton that covered the cephalothorax called the carapace. The abdomen located behind the cephalothorax and consisted of six clearly divided segments. The ventral aspect of the cephalothorax was represented by the sternum which was triangular in shape with it's apex rostrally and it's base caudally, consisted of five fused sternebra. Each sternebra gave one pair of preopodes or walking legs connected by membranous joint. The chelipeds were the largest claws that the crayfish used for defence and to capture prey. Each of the four remaining segments contained a pair of walking legs. The walking leg composed of six segments, the coax, basis, ischium, merus, carpus and the palm, these segments connected with each other by membranous joints.

Key words

Procambarus Clarckii, Preopodes, Chelipeds, Coax, Basis, Ischium, Merus, Carpus and Palm