Diet of Pseudechinus magellanicus (Echinoidea: Temnopleuridae) in Argentinean waters.

BIGATTI, G.; PENCHASZADEH, P. E.; MILOSLAVICH, P. A.

Pto. Varas

Congreso; Sea Urchins and aquaculture; 2003

The gut contents of Pseudechinus magellanicus (philippi, 1857) coIlectedfrom different habitats from Buenos Aires to Usuhaia were analyzed. In littoralmussel banks of the Province of Buenos Aires at 50 m depth, the most importantfood item was Mytilus edulis platensis. In communities without M. edulis thefood preferences were Balanus sp., foraminiferans, polychaetes and algae. Inbeds of the mytilid Aulacomya atra at 5-lOm depth, the main food items were theoyster spat and different algae: Rodophyceae, filamentous algae and Ectocarpussp. In Usuhaia the sea urchin preyed on ostracods, foraminiferans and algae. Ourdata indicate that P.magellanicus from Argentina is omnivorous, consuming anyavailable food resource: capture drift algae with the tube feet, graze on sessilealgae and predate on animals. Results suggest that this species playa relevantrole in the community structure, main1yby an intense predation on bivalve spat.