NEW DATA ON THE OCCURRENCE OF TWO LESSEPSIAN MARINE HETEROBRANCHS, PLOCAMOPHERUS OCELLATUS (NUDIBRANCHIA: POLYCERIDAE) AND LAMPROHAMINOEA OVALIS (CEPHALASPIDEA: HAMINOEIDAE), FROM THE AEGEAN SEA

The authors have recently collected two Lessepsian heterobranchs from Turkey, namely Plocamopherus ocellatus Rüppell & Leuckart, 1828 and Lamprohaminoea ovalis (Pease, 1868), both of which were found significantly out of their known distribution ranges. The single individual of P. ocellatus collected at Akbük Cove is a new addition to the Aegean Sea malacofauna, while several individuals of L. ovalis observed from the Ayvalık Islands Nature Park and Saros Bay represent the northernmost occurrence limit of the species. Present findings suggest that P. ocellatus is currently a casual alien species in the region, while L. ovalis has established a breeding population in the northern Aegean Sea.