Biogeographia vol. XXI V - 2003 (Printed October, 3131‘ 2003) Marine biogeography of the Mediterranean Sea: patterns and dynamics of biodiversity Mediterranean calanoid copepods biogeography: new species identification and first records of hyperbenthic forms GIACOMO ZAGAMI, 1\/LARINA CAMPOLMI, ANTONIA GRANATA Dz'pzzrtz'mmt0 zli Biologizz Azzimzzle ed Ecologizl Mzzrmzz, Unit/ersitfz di Messinzz, Szzlitzz Sperone, 3], 1—98]66, Messimz (Italy) Keywords: Calanoid copepods, plankton, hyperbenthos, biogeography, Mediterranean Sea, biodiversity. SUMMARY The spatio-temporal distribution patterns of the Mediterranean planktonic and hyperbenthic calanoid copepods were analysed. The atlantic origin 0F the major part ofplanlttonic calanoid copepods was defined, distinguishing between Mediterranean own species and the Alboran Sea, and Levantine Bacin populations migrated, rispectively, From Atlantic and Indo—Pacific Oceans. In the Mediterranean the presence, as other oceans of the world. of a hyperbenthic specific calanoid copepods community was showed. In this “ecological group” were identified populations ofatlantic and indo- pacific origin. of recent and ancient migration in the Mediterranean. lNTRODUCTION Copepoda, a subclass of the phylum Crustacea, consists of ten orders: Platycopioida, Calanoida, Misophrioida, Mormonilloida, Cyclopoida, Geliyelloida, Harpacticoida, Poecilostomatoida, Siphonostomatoida and Monstrilloida. Copepods are aquatic, mainly marine, organisms that have spread by adaptive radiation into all habitats, including the ocean depths, brackish coastal lagoons, submarine caves, and fresh waters of high mountain rivers and lakes. Humes (1994) estimated that by the end of 1993 about 11,500 species of Copepoda had been identified. Excluding Diaptomidae, around 1800 species of Copepoda Calanoida have been censused in the marine ecosystem (Huys and Boxshall, 1991; Humes, 1994). In their inventory of Mediterranean planktonic Copepoda, Razouls and Durand (1991) listed 301 species of Calanoida, to which must be added 11 new species identified between 1991 and 2000 for a total of312 species. There are records of 173 species of Copepoda Calanoida in Italian seas (Argano et al., 1995), i.e. 55.8% of the total identified in the Mediterranean. Since there