Author: de Buen, 1959
See diagnostic features and key to species.
Body moderately slender, trunk slightly tapering toward head. Snout mode- rately long, broad, and bell-shaped, pre- 4 oral snout about 7 to 8% of total length; gill slits of moderate size, much less than eye length; gill septa without pro- jecting medial lobes or pleats but with incised margins; eyes small in adults, between 3 and 4% of total length; nostrils narrow, their width about equal to internarial space; incurrent and excurrent apertures moderately large and oval, anterior nasal flaps long and angular; mouth long, moderately large, and broadly arched, with dental bands not expanded and with lower ones falling just behind uppers; mouth and labial furrows extending slightly in front of eyes; labial folds not enlarged, with lowers diagonal to body axis; mouth and teeth not enlarged in males. Interdorsal spaceabout 1.5 times first dorsal base, slightly greater than preorbital snout and considerably greater than preoral snout; first dorsal fin about as large as second, bases about equally long; origin of first dorsal about opposite pelvic midbases; second dorsal insertion about opposite anal insertion; pectoral fins moderately large, anterior margins about 12 to 14% of total length; inner margins long, about 3/5 of pectoral bases; interspace between pectoral and pelvic bases fairly short, about 2/3 of prebranchial length and about 14% of total length in adults; pelvic fins low and angular; anal fin moderately long, high, and angular, slightly more or less than three times as long as high, its base slightly greater than prespiracular space and 12 to 15% of total length in adults. No dorsal crest of enlarged caudal denticles. Lateral trunk denticles of body with crowns fairly flat, skin surface smooth and without feltlike or fuzzy texture. Colour medium brown, grey or grey-blackish, without conspicuous markings on fins. Adults moderately large, to 56 cm.
Eastern Pacific: Gulf of, Panama, Ecuador and central Chile. Also nominally recorded from the eastern North Atlantic off Morocco, but identificationuncertain.
Habitat and Biology:
A little-known bottom-dwelling shark of the upper continental slopes on or near the bottono at 400 to 925 m depth in the eastern Pacific. Nominal records off Morocco have this species at 500 to 1000 m depth, but this is uncertain.
Maximum total length 59 cm, adults males from 51 to 59 cm, females not reported.
Interest to Fisheries:
It is uncertain at present if this species occurs in the eastera North Pacific or not, where it may have been confused with A. brunneus. Eastern Atlantic records by Golovan (1978) may be based on some other species. The illustration is based on drawings by the writer of an adult male from Valparaiso, Chile.
Holotype: Estacion de Biologia Marina, Universidad de Chile, EBMCh. 10.184, 594 mm adult male, apparently lost? Type Locality: Near Valparaiso, Chile, eastern South Pacific, 400 m depth.