Acteon (Maxacteon) hancocki (Rudman, 1971) Maxacteon hancocki is a species of small sea snail, a marine opisthobranch gastropod mollusk in the family Acteonidae, the barrel bubble snails.
It has a headshield with a pair of fleshy lobes; thin operculum.
The white shell shows orange-brown markings at the base and at the apex.
The large columella is slightly twisted.
The shell is sculptured with grooves This species is found in moderately deep water off the northern coast of North Island, New Zealand.