The larval development of palaemonid shrimps from the Amazon Region reared in the laboratory. IV . Abbreviated development of Palaemonetes ivonicus HOLTHUIS , 1950 (Crustacea: Decapoda)

Abstract

The larval development of the freshwater shrimp Palaemonetes ivonicus was studied under laboratory conditions, based upon offsprings of ovigerous females collected in a várzea lake of the Solimões River system. The females carry few (I2 to 43), large (2.31 I 0.14 x 1.49 I 0.09 mm), yolk rich eggs. The species goes through three larval stages without feeding. The newly-hatched larva has sessile eyes and ail the appendages, except for the uropods; however, some of the appendages still exhibit a rudimentary form Larva I1 has stalked eyes and functional walking legs. Larva 111 has free uropods. Metamorphosis occurs between four and six days after hatching. Descriptions and illustrations of the larval and first juvenile stages are given