Eocene isopods of Pesciara di Bolca (Italy) revisited

The scarcity of the isopod material of the fossil sites from the "Pesciara di Bolca" (Verona Province, Northern Italy) did not leave much room up to now for conclusions concerning the systematic relationship of this fauna. In this study, we reinvestigate fossils of the cymothoidan Palaega acuticauda Secretan, 1975 and the sphaeromatidean Heterosphaeroma veronensis Secretan, 1975. We argue that both species do not differ substantially in dorsal morphology from recent genera, and we place them among more likely congeners: Cirolana acuticauda n. comb., and Dynamenella veronensis n. comb. A detailed redescription of both species is made on the basis of additional material that came from Pesciara di Bolca and Monte Postale marine fish and terrestrial plant bearing layers. Two environmental scenarios are discussed: one in which the palaeoenvironment is thought to be mainly lacustrine, another in which discoveries of more fossil sphaeromatideans and other cymothoidans in Italy suggest seawater affinities, coral reef environments, or estuarine conditions.