Morphological variations of benthic foraminiferal tests from holocene sediments of Punta Campanella shelf (Southern Tyrrhenian sea).

We investigated the distribution and presence of theratological specimens in benthonic foraminiferal assemblages along the coast of the Sorrento Peninsula (southern part of the Tyrrhenian margin). Thirtyeight samples were analyzed from surficial shallow water sediments and a total of 97 benthonic foraminiferal species, belonging to 21 families, were identified along the shelf zone (between -6 and -102 m). Calcareous forms were dominant and equal to 82.6 % of the total population, whereas agglutinated forms characterised only 17.4 % of the total assemblage. A small number of specimens, related to eleven species, Connemarella rudis, Quinqueloculina disparilis, Q. milletti, Q. seminulumsp., Adelosina pulchella, Peneroplis pertusus, Asterigerinata mamilla, Elphidium crispum, Cibicides lobatulus and Planorbulina mediterranensis, from six calcareous families and one agglutinated familyten distinct types of morphological deformities of their tests. These include: (1) aberrant chamber shape and lack of sculpture; (2) aberrant shape of last chamber; (3) abnormal growth of last chamber; (4) double aperture; (5) wrong coiling; (6) anomalous protuberance; (7) tendency to siamese twin; (8) high spire giving a spiroconvex test, (9) additional chambers and (10) poor development. Morphological deformities are independent of latitude, taxonomic position, mode of life, and feeding strategy of foraminifera. They can occur within the range of natural variability of a givgiven environmental conditions. Benthonic foraminifera can reflect human-induced environmental perturbation and can be used as bioindicators for monitoring coastal pollution.