Catshark egg case
During a scuba dive I encountered this Catshark egg attached to an abandoned anchor rope on the seabed. The Catshark is a predominantly nocturnal fish that hides in the burrows and ravines of submerged cliffs during the day. Typically this small shark fixes its eggs to the various Gorgonians to make the most of the sea currents. In this case, as there were no Gorgonians in the seabed, he used the rope abandoned on the bottom by a boat.