Author: (Misra, 1962)
Field Marks:
An Apristurus with the first dorsal base elongated anteriorly as a low ridge, and a moderately well-developed caudal crest of denticles.
Diagnostic Features:
Body relatively slender, trunk slightly tapering toward head. Snout long, broad, and bell-shaped, preoral snout about 11% of total length; gill slits small, about half of eye length; gill septa incised, without pleats or projecting medial lobes; eyes small, about 2.5% of total length; nostrils very broad, their width about equal to internarial space; incurrent apertures of nostrils fairly narrow and almost slitlike, anterior nasal flaps very low and rounded; mouth short, moderately large, and very broadly arched, with dental bands hardly expanded and with lower ones falling well behind uppers; mouth and labial furrows extending slightly in front of eyes; labial folds not enlarged, with lowers diagonal to body axis. Interdorsal space equal to or slightly less than first dorsal base, about 3/4 of preorbital snout; first dorsal fin about 3/4 as large as second, but first dorsal base with an anterior ridgelike elongation and about 1.5 times the length of second dorsal base; origin of first expanded anteriorly to over first fourth of pelvic bases; second dorsal insertion slightly in front of anal insertion; pectoral fins moderately large, about 13% of total length; inner margins long, nearly the length of pectoral bases; interspace between pectoral and pelvic bases short, about 2/3 of preorbital length and about 7% of total length; pelvic fins fairly low and broadly rounded; anal fin long, rather high, and rounded-angular, almost 4 times as long as high, its base almost equal to prebranchial space and 17% of total length; caudal fin rather broad, with a welldeveloped crest of enlarged denticles on dorsal margin. Lateral trunk denticles with crowns close-set and somewhat elevated, giving body a rough surface. Colour medium brown. Adult size unknown.
Geographical Distribution:
Known only from the type locality (holotype only), in the Andaman Sea.
Habitat and Biology:
A deepwater bottom shark, from the eastern Indian ocean continental slope at 1040 m depth.
Size:
Maximum 26+ cm (presumably immature at this size).
Interest to Fisheries:
None at present.
Remarks:
Diagnostic characters and the above illustration are from the holotype, examined by the writer in Calcutta in 1982. The species is very much like A. indicus in its general shape and long first dorsal base, but differs from a similar-sized specimen of that species in having smaller pectoral fins, narrower nostrils, much lower pelvic fins, a much shorter, broader caudal fin, possibly a slightly longer abdomen, and apparently a well-developed supracaudal crest.
Type material:
Holotype: Zoological Survey of India, ZSI-F 1, 627/2, 242 mm female. Type Locality. 11° 46'N, 93° 10'E, Andaman Sea.