Diatoms as food source indicator for some Antarctic Cumacea and Tanaidacea (Crustacea)

Abstract

The gut contents of three species of cumaceans: Eudorella splendida, Vaunthompsonia inermis and Campylaspis maculata, and three species of tanaids: Nototanais antarcticus, N. dimorphus and Peraeospinosus pushkini from the shelf of Admiralty Bay and two cumaceans: Diastylis mawsoni and Ekleptostylis debroyeri from the deeper Antarctic shelf were studied. With the exception of Campylaspis maculata, which is a predator or scavenger, and Ekleptostylis debroyeri, whose gut was filled with mud only, detritus was an important diet component of all the species studied. On the basis of qualitative and quantitative components of diatom taxa it can be concluded that the food of Diastylis mawsoni comes from the pelagial, whereas the food of the other peracarids is of benthic origin. Species inhabiting the shallowest waters consume almost exclusively epipelic food, whilst those living below the euphotic zone feed mostly on particles sedimented from the pelagial; taxa occurring at intermediate depths feed on pelagic matter, but also of epiphytic and of epipelic origin.