 They are found on or near the bottoms of insular continental slopes, at depths of 570 to 1,480 meters.In 2002, the spongehead catshark was seen alive in its natural habitat for the first time, from the submersible "Pisces IV" at a depth of about a kilometer, on the Northampton Seamount off the northwestern Hawaiian Islands.The spongehead catshark has a thick body and head, with a moderately long, broadly rounded snout.