First record of Paradiopatra bihanica ( Polychaeta , onuphidae ) in the Adriatic Sea

Paradioatra bihanica (Intes and Le Loeuff, 1975) is a polychaete species belonging to the family Onuphidae. Members of this family occurs in all oceans from intertidal to the deepest depths (FAUCHALD & JUMARS, 1979; FAUCHALD, 1980; PAXTON, 1986; BUDAEVA & ROGACHEVA, 2013), inhabiting various biotopes and occasionally reaching very high densities (BAILEYBROCK, 1984). These species range in length from a few centimeters to 3 meters (PAXTON, 1986). Most of them are tubicolous and can live permanently in rather sturdy tubes (deep-water species), in fragile (shallow water species) or in very fragile temporary tubes (sandy beaches species; PETTIBONE, 1963; PAXTON, 1979; FAUCHALD, 1980; PAXTON, 1986). Up to now regarding the Italian Seas P. bihanica has been found only in the Tyrrhenian and in the Ionian Seas (CASTELLI et al., 2008) with the synonym of Paradiopatra. calliopae Arvanitidis & Koukouras 1997 (BUDAEVA & FAUCHALD, 2011; PAXTON & BUDAEVA, 2013; ҀINAR et al., 2014.; PAXTON, 2015a). This paper reports for the first time the occurrence of P. bihanica in the Adriatic Sea with the aim of increasing the range extension of its geographical distribution.