Phylum: Chordata - Class: Actinopterygii - Order: Perciformes - Family: Anarrhichadidae
Although they look very much like true eels, these are not bony fish; they have a cartilaginous skeleton. They also have a fearsome bite, with stout canine teeth at the front of the mouth and powerful molars at the rear.
The wolf eel has no pelvic fins and lacks a lateral line. The dorsal fin reaches almost to the tail and comprises flexible spines but no soft rays. The colour is mainly grey or greyish-brown or dark olive, and occasionally mottled. Young wolf eels often have an orange tinge and dark stripes at rear of body.
The head is all that is usually visible, because the wolf eel hides away in crevices in rocky areas and under boulders well away from the inter-tidal zone.
The male, shown here, has huge lips and a bump on the top of its head. Their favourite food is reported to be sea urchins. A wolf eel is reported to grow to a length of 2m, and it is said to be very good to eat despite its ugly appearance.