Author: (Brauer, 1906)
An Apristurus with first dorsal base expanded anteriorly as a long low ridge, and without a caudal crest.
Body relatively slender, trunk slightly tapering toward head. Snout rather long, very broad, and bell-shaped, preoral snout about 9 to 10% of total length; gill slits moderately small, about 1/2 to 2/3 of eye length; gill septa not incised, with or without short, projecting medial lobes; eyes small, between 2 and 3% of total length; nostrils large, their width about eoual to internarial space: incurrent and excurrent apertures fairly large and oval, anterior nasal flaps expanded and angular; mouth short, large, and very broadly arched, with dental bands hardly expanded and with lower ones falling just behind uppers; mouth and labial furrows extending below eyes; labial folds not enlarged, with lowers diagonal to body axis. Interdorsal space about 2/3of first dorsal base and preorbital snout; first dorsal fin about two-thirds of area of second, but first dorsal base elongated anteriorly as a low ridge and nearly twice the length of second dorsal base; origin of first dorsal extending slightly anterior to pelvic midbases; second dorsal insertion slightly in front of anal insertion; pectoral fins rather large, anterior margins about 13% of total length; inner margins long, nearly the length of pectoral bases; interspace between pectoral and pelvic bases very short, about 2/3 of preorbital snout and about 7% of total length; pelvic fins very high and broadly rounded; anal fin very long, high, and angular, nearly 4 times as long as high, its base about equal to prebranchial space and 16 to 20% of total length; caudal fin very long and narrow, without a crest of enlarged denticles on dorsal margin. Lateral trunk denticles with crowns close-set and fairly flat, body surface smooth and not with a feltlike or fuzzy texture. Colour brownish or blackish. Adults size unknown.
Western Indian Ocean: Somalia, Gulf of Aden, Oman; possibly also eastern South Atlantic off Namibia and South Africa.
Habitat and Biology:
A little-known deepwater bottom catshark, from the East African continental slopes at 1289 to 1840 m: depth.
Maximum 34+ cm (immatures).
Interest to Fisheries:
Characters of the diagnosis above are taken in part from a specimen of this species examined by the writer in the British Museum (Natural History), BMNH 19188.8.131.52, 22.7 cm immature female, Gulf of Aden at 1061 to 1080 m depth, as well as from Springer (1979).
Lectotype: Zoolgisches Museum an der Humboldt-Universität zu Berlin, ZMB 22424, 336 mm female, designated by Springer (1979:19). Type Locality: 02° 59'N, 47°06'E, off coast of Somalia, Indian Ocean.