Spongillidi (Porifera, Demospongiae) del Fiume Temo (Sardegna nord-occidentale)

This work concerns a) presence, distribution and life cycle of spongillids from River Temo catchment basin and b) possible morpho-functional and life cycle adaptations in relation to environmental conditions. Samplings were carried out from 1984 to 1993 in seven sites located on the principal water-course and tributaries. Results showed the presence of sponges, in all stations but the river mouth, belonging toEphydatia fluviatilis. The presence of only this species seems to be related to its great plasticity allowing to adapt populations to a large range of water and climatic regimes. The steady presence of gemmules in all seasons may be seen as a strategy to face springer-autumnal floods and summer drought. These sponges show a high morphological uniformity, such as crusty shape and small size, whereas gemmuloscleres morphometry is very variable.