Featured Elasmobranch – Eastern Pacific Black Ghostshark
by kjames ~ October 1st, 2009. Filed under: Featured Elasmobranch.
Photo Courtesy of Monterey Bay Aquarium Research Institute 2003
Eastern Pacific Black Ghostshark
October 2009
Hydrolagus melanophasma
Family Chimaeridae
Identification: A chimaera of the genus Hydrolagus, which lack an anal fin, it has a fairly large, torpedo-like body, tapering from its blunt snout to a short whip-like tail filament. It has large, triangular pectoral fins, a long, slightly curved spine that precedes the first dorsal fin and a second dorsal fin that is of a uniform height throughout. Coloration is a uniform black with a lighter band across its snout, but has no other distinct markings or mottlings.
Size: A large-bodied chimaera with an observed maximum length of 110 cm (male); based on only a very few specimens. It may grow as a larger maximum size.
Distribution: Known from off southern California with observations occurring near the Channel Islands to the tip of Baja California and into the Gulf of California.
Habitat: A deep-water species it has been observed on Remote Operated Vehicle (ROV) dives by the Monterey Bay Aquarium Research Institute at depths between 1550 and 1670 meters. Documented collections of this species have been from 30.5 to 1400 meters. It has been observed from ROV video footage to occur over soft substrate with minimal to no rocky relief.
Biology: An oviparous species. Males mature at 92.6 cm total length, but little else is known of its biology. It has been observed on ROV video footage associating with congeners and with the longnose chimaera (Harriotta raleighana).
General interest: The species was first collected and recognized as being new to science by the late Carl L. Hubbs (Scripps Institute of Oceanography) in 1965. However, the species has only recently been described (James et al. 2009). It is caught in sablefish traps as bycatch and has on occasion been caught by hook and line by recreational anglers.
By Kelsey C. James
Pacific Shark Research Center
Moss Landing Marine Laboratories
8272 Moss Landing Road
Moss Landing, CA 95039
kjames@mlml.calstate.edu
Reference:
James, K.C., Ebert, D.A., Long, D.J., & Didier, D.A. 2009. A new species of chimaera, Hydrolagus melanophasma sp. nov. (Chondrichthyes: Chimaeriformes: Chimaeridae), from the eastern North Pacific. Zootaxa 2218: 59-68.