LARVAL DEVELOPMENT OF THE PALAEMONID PRAWN, MACROBRACHIUM-LANCHESTERI(DEMAN) REARED IN THE LABORATORY (DECAPODA, CARIDEA)

The larval development of the palaemonid prawn, Macrobrachium lanchest eri (De Man) was observed under laboratory conditions. Metamorphosis t o post-larva was first observed 30 days after hatching at a temperatur e of 26-degrees-28-degrees-C and in freshwater. Nine larval stages (Zo ea I to Zoea IX) were observed and described. The pattern of developme nt is considered in relation to other Macrobrachium species with simil ar number of larval stages. In relation to larval developmental mode, M. lanchesteri is most similar to M. niloticum from northern Africa. T hese are the only species in the genus with the fifth pereiopod appear ing as a rudimentary bud in the first larval stage and fully formed by the second or the third stage. The size of the fifth pereiopod is als o considerably larger than in other species of the genus at the same s tage of development.