A couple of butterfly blenny (Blennius ocellaris) peeps out from inside a fan mussel (Pinna nobilis), that they chose as the nest for hatching their eggs.

underwater underwater photography nature nature photography sea mediterranean sea macro macro photography wildlife saltwater fish butterfly blenny blennius ocellaris bavosa occhiuta pinna nobilis nacchera fan mussel italy calabria saline joniche color photography landscape behavior nest hatching eggs snoot two couple reproduction close up unique eyes biology