RELATIONSHIPS BETWEEN <i>PATELLA FERRUGINEA</i> GMELIN, 1791 AND THE OTHER TYRRHENIAN SPECIES OF <i>PATELLA</i> (GASTROPODA: PATELLIDAE)

Abstract

The external morphology of soft parts of the rare Patella ferruginea Gmelin, 1791 is described, and its relationships with P. caerulea, P. rustica and P. ulys-siponensis are investigated on both morphological and electrophoretic grounds. Soft part morphology is a good discriminative tool, but of little help in detecting affinities. Electrophoretic data on 19 presumptive loci suggest that P. rustica is the closest species to P. ferruginea, whereas P. caerulea and P. ulyssiponensis are clustered separately. Mean observed heterozyg-osities arc higher in P. ferruginea and P. rustica. It is concluded that in case of subdivision of the genus Patella L., 1758, P. ferruginea and P. rustica should be placed together in the subgenus Patellastra Mon-terosato, 1884.