The Freshwater shrimp Paratya australiensis (Kemp, 1917) (Decapoda:Atyidae) in estuaries of south-westren victoria, Australia

Abstract

All life-cycle stages of Paratya australiensis, formerly thought to occur predominantly in freshwater environments, were found to be common in estuaries of western Victoria. Highest densities of larvae were found below the halocline in stable, open, well developed, salt-wedge estuaries. Larvae developed in the salt wedge, and juveniles recruited to littoral weed beds. Adults were most abundant in low salinities among submerged, leafy macrophytes. Although recruitment to estuaries permits the avoidance of fatal drift of larvae to sea, tolerance of saline conditions may permit rare dispersal of larvae between estuaries. A new model for the biogeography of Paratya is proposed.