chimaeras

This strange cartilaginous fish uses its long snout to scan over the sea floor for the electrical impulses of its prey that bury in the muddy sea floor, just like a metal detector. Like other chimaeras (such as ghost and elephant sharks), these animals lay horny egg cases in which their young are left to develop, potentially for up to one year. For defense, most chimaeras have a venomous spine located in front of the dorsal fin.

http://www.who-sucks.com/animals/real-life-sea-monsters-24-bizarre-creatures-of-the-deep

http://en.wikipedia.org/wiki/Chimaera