Bighead Catshark

This moderately-large species has the following characters: labial furrows of upper and lower subequal in length; relatively short preorbital snout; very robust head, its width (at mouth corners) 13.9% TL; large mouth, its width 11.1% TL; large orbit, its length 3.7% TL; relatively long length of prepectoral and prepelvic; first dorsal fin is slightly smaller than second one, its origin well forward of pelvic fin insertion; tall anal fin, short based, triangular in shape; widely spaced dermal denticles, moderately large, deciduous, with long medial cusps; species size to at least 67.5 cm TL; uniformly medium yellowish brown body and fins ; about 66 teeth rows in upper jaw, about 55 rows in lower jaw; adult female teeth with 5 cusps, 1 very long medial cusp, 2 much shorter inner lateral cusps, 2 much shorter outer lateral cusps situated anteriorly to inner lateral cusps; 35 monospondylous vertebrae; 26 diplospondylous precaudal vertebrae; about 108 total vertebrae (Ref. 76944).

The bighead catshark (Apristurus bucephalus) is a species of fish in the family Scyliorhinidae endemic to Australia. Its natural habitat is the open seas. It belongs to a genus of poorly known deep-water catsharks, and is recorded from only three specimens taken off Perth, Western Australia. This species could be rare or uncommon, and the effects of fisheries are unknown, though if its biology is like other deep-water shark species, it may not be sufficiently fecund to withstand exploitation pressures.