Comparison of feeding mechanisms in two intertidal gammarideans, Hyale rupicola (Haswell) and Paracalliope australis (Haswell) (Crustacea : Amphipoda)

Abstract

The feeding mechanisms of two rocky shore, intertidal, gammaridean amphipods are described. H. rupicola inhabits the lower intertidal zone and grazes primarily on macro-algae. P. australis inhabits rock pools of the littoral fringe. These pools are flushed with seawater only during rough seas and during periods of calm have a layer of amphipod faecal pellets covering the bottom. No macro-algae grow in these pools. P. australis is microphagous, grazing micro-algae from the rocks and from the faecal pellet layer. In addition to grazing, both species exhibit setal transfer feeding on the material cleaned from the body. P. australis also appears capable of filter feeding by an action involving only the mouthparts.