|Scientific Name:||Centrophorus isodon|
|Species Authority:||(Chu, Meng & Liu, 1981)|
Pseudocentrophorus isodon Chu, Meng & Liu, 1981
Centrophorus is diagnosed by teeth more or less differentiated in upper and lower jaws, the uppers being relatively broad and blade-like, the lowers being larger, broad and blade-like with erect to oblique cusps; angular to elongated tips to the inner margin of the pectoral fins; dorsal spines grooved laterally; no pits or lateral keels on the caudal peduncle; tip of upper caudal expanded with a conspicuous subterminal notch.
C. isodon is a distinctive species, with a black mouth and tongue, blackish grey dorsally with dusky anterior margins to the second dorsal fin and upper caudal lobe; relatively small gill slits; large second dorsal fin, almost as high as first; pectoral inner margin elongated, reaching to about mid base of first dorsal fin; trunk denticles not overlapping, sessile, shield-shaped crowns with a single cusp and strong longitudinal ridge, a smaller ridge set at an angle on each side of the main one; upper teeth similar to lowers, only slightly smaller, also with a strongly oblique cusp; about 25 arched dermal folds on the "chin" behind the mouth.
|Red List Category & Criteria:||Data Deficient ver 3.1|
|Assessor(s):||Duffy, C. (Deepsea Chondrichthyan Workshop, November 2003)|
|Reviewer(s):||Kyne, P.M., Cavanagh, R.D. & Fowler, S.L. (Shark Red List Authority)|
A rare, little-known deepwater dogfish with sporadic records in the Indian and Pacific Oceans. May be more wide-ranging than the records suggest. Inhabits upper continental and insular slopes and has been recorded at depths of 760 to 770 m. Maximum reported size 93 cm total length (TL). Nothing known of its biology, but related species generally have very low fecundity. Other members of the genus exhibit little resilience to fishing pressure and have been rapidly depleted by directed commercial fisheries, and as bycatch. Further research and monitoring of deepsea fisheries as they expand globally is necessary. Insufficient information is available to assess this species beyond Data Deficient at this time.
|Range Description:||Known from the Indian Ocean (Maldive Islands, possibly Sri Lanka), South China Sea and Western Central Pacific Ocean (Philippines).|
Native:Disputed Territory; Hong Kong; Maldives; Philippines
|FAO Marine Fishing Areas:||
Present - origin uncertain:
Indian Ocean – eastern; Indian Ocean – western; Pacific – northwest; Pacific – western central
|Range Map:||Click here to open the map viewer and explore range.|
|Habitat and Ecology:||
Inhabits upper continental and insular slopes, recorded depths: 760 to 770 m (Compagno in preparation a). Centrophorus spp. usually occur on or near the bottom over the continental slope from about 200 to 2,300 m depth.
Reported size ranges from 35.2 to 93 cm total length (TL). Size and age at maturity is unknown. Smallest reported adult male is 75 cm TL; smallest reported adult female is 78 cm TL (Compagno in preparation a). All other aspects of biology unknown.
Reproduction in Centrophorus is ovoviviparous, and fecundity is low. C. uyato and C. moluccensis (which superficially resemble C. isodon) only have 1 to 2 embryos per litter, compared to 5 to 7 per litter in C. squamosus and C. lusitanicus respectively.
Diet includes a wide range of teleosts, other dogfishes, cephalopods, shrimps and occasionally salps.
Probably taken as bycatch in deepwater trawl and line fisheries. Other members of the genus exhibit little resilience to fishing pressure and have been rapidly depleted by directed commercial fisheries, and as bycatch (Cavanagh et al. 2003). Further research and monitoring of deepsea fisheries as they expand globally is necessary.
Utilisation unknown. Probably utilized for liver oil and possibly fish meal.
|Conservation Actions:||No conservation measures are in place for this species.|
|Citation:||Duffy, C. (Deepsea Chondrichthyan Workshop, November 2003) 2004. Centrophorus isodon. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 07 July 2015.|