TAXONOMIC AND ECOLOGICAL REMARKS ON BORING SPONGES (CLIONIDAE) FROM THE STRAITS OF GIBRALTAR (SOUTHERN SPAIN) - TENTATIVE BIOINDICATORS

An important programme of biomonitoring along the coast of Algeciras B ay (Straits of Gibraltar) has allowed us tentatively to consider six s pecies of boring sponges of the genus Cliona as biological indicators: Cliona celata, C. viridis, C. rhodensis, C. vermifera, C. schmidti an d C. vastifica. The taxonomy and distribution of these species have be en considered in this paper. Ecological observations have permitted us to identify some important characteristics of their habitat on the ba sis of local environmental parameters. Cliona viridis and C. celata wi thstand sedimentation higher than 7 gr/m(2) and a solid suspension of 38 mg/l. Cliona vermifera and C. schmidti did not tolerate sedimentati on higher than 1 gr/m(2). One of these, C. vermifera Hancock, is recor ded for the first time in the Iberian Peninsula.