ECOLOGY OF INTERTIDAL SEA-ANEMONES, DENSITY, DISPERSION AND AUTOECOLOGY OF PHYMACTIS-CLEMATIS DANA, 1849 (ANTHOZOA, ACTINIARIA)

A study was conducted on the species Phymactis clematis Dana, 1849 (An thozoa: Actiniaria) in the intertidal zone of Mar del Plata and Santa Clara del Mar (Province of Buenos Aires, Argentina). A great number of this species lives in protected microhabitats such as crevices, and t ends to be larger than those in exposed areas. The specimens from the protected zones appear to have better environmental conditions, due to a greater concentration of oxygen and food in the remnant sea water d uring low tides. The dispersion of P. clematis is aggregated and the p opulation density is variable. The highest values were recorded in Pla ya Punta Cantera (Mar del Plata) in comparison to Santa Clara del Mar.