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Biological Profiles

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South Florida Aquatic Environments About the Different Groups of Fishes About the Anatomy of Fish and Sharks How Fish and Sharks Swim About Fish Adaptations About the Endangered Species Act How to Become a Biologist About Careers In Ichthyology Most Commonly Asked Shark Questions Most Commonly Asked Sawfish Questions Most Commonly Asked Ray and Skate Questions Most Commonly Asked Fish Questions Identification Key to Freshwater Fishes of Peninsular Florida Field Key to Sharks Skates of the Western Gulf of Maine Project Shark Awareness - A Public Outreach Educational Program Shark Fishing in U.S. Territorial Waters Most Commonly Asked Sawfish Questions Sawfish In Peril - PowerPoint file Sawfish Informational Brochure - Acrobat file Sawfish Outreach Boat Ramp/Marina Sign - Acrobat file Sawfish References Sawfish Links Smalltooth Sawfish species profile Largetooth Sawfish species profile Green Sawfish species profile Freshwater Sawfish species profile Dwarf Sawfish species profile Knifetooth Sawfish species profile Chondrichthyes Bibliography Search Freshwater Fishes of Florida References General Fish References Shark References Sawfish References Childrens' Shark Books Stingray Reproduction References Biological Profiles Glossary of Terms Shark Games: Test Your Knowlege! 2003 Open House Photos BLACK DOGFISH Order - Squaliformes Family - Etmopteridae Genus - Centroscyllium Species - fabricii Taxonomy This species was originally described as Spinax fabricii by Reinhart in 1825. This name was later changed to the currently valid Centroscyllium fabricii (Reinhart 1825). There are no known synonyms appearing in past scientific literature. The genus name Centroscyllium is derived from the Greek, kentron which means "sting" and the Greek, skylla which means "a kind of shark". Common Names The English language common name for this species is black dogfish. Common names in other languages include aiguillat (French), fabricius sorthaj (Danish), svart pigghaj (Swedish), svartháfur (Icelandic), svarthávur (Faroese), tollo negro (Spanish), tollo negro merga (Spanish), and zwarte lantaarnhaai (Dutch). Geographical Distribution The range of the black dogfish in the western North Atlantic from Baffin Island and Greenland south to the Gulf of Mexico and in the eastern North Atlantic from Iceland south to Senegal and Guinea to Namibia. This species has also been observed off southern Argentina in the western South Atlantic. World distribution map for the black dogfish Habitat Black dogfish are primarily a deepwater, benthic species usually confined to the outer continental shelf and the upper continental shelf. However they have been occasionally taken near the surface in arctic waters and during periods of maximum cold and darkness. They haven been collected from as deep as 5,250 feet (1,600 m) and temperatures as low as 34°F (1°C), but are most common at 1,800-3,280 feet (550-1,000 m) and temperatures of 38-40°F (3.5-4.5 °C). Some sexual and size segregation, schooling, and spring-winter inshore migration may occur. Biology Black dogfish source: FAO Sharks of the World · Distinctive Features The body of the black dogfish is moderately stout and compressed with a short caudal peduncle and a long abdomen. The snout is moderately long with an arched mouth. The second dorsal fin is much larger than the first dorsal fin and originates over the midpelvic base. Both dorsal fins have prominent, grooved spines. The anal fin is absent. The pectoral fins are adpressed and fall short of the first dorsal fin origin. Black dogfish dentition: underside of head source: FAO Sharks of the World This species may be confused with the great lanternshark (Etmopterus princeps), however they differ in lower tooth shape (multicuspid vs. blade-like) and the origin of the second dorsal fin (at level of midpelvic base vs. near posterior pelvic base). They are distinguished from the spiny dogfish (Squalus acanthias) in having deeply grooved dorsal spines (vs. rounded), in placement of the second dorsal fin (origin near rear pelvic base in Squalus), and in tooth shape (bladelike in both jaws in Squalus). · Coloration Adult and subadult black dogfish are uniformly blackish brown without any obvious black markings above the pelvic fins, ventrally on the caudal penduncle, or laterally on the upper caudal lobe. Juvenile black dogfish are dark black ventrally and lighter black to brown dorsally with white-edged dorsal, pectoral, and pelvic fins. Spines are white in all sized of black dogfish. The eyes are a reflective green when first caught. Black dogfish dentition: upper and lower teeth source: FAO Sharks of the World · Dentition The upper and lower teeth are numerous and similar in shape with a single large, erect cusp, and two (occasionally four) smaller, erect cusplets. The upper and lower jaws each consist of 68 teeth. · Dermal Denticles Denticles of the black dogfish are close-set. They are short and conical with hooked cusps and ridged, stellate bases. Thought to be bioluminescent, the skin contains minute, deeply pigmented dots similar to those seen in other luminescent squaloid species. · Size, Age & Growth Black dogfish reach a maximum length of approximately 35 inches (90 cm), however they are common as adults at lengths of 23.6-29.5 inches (60-75 cm). · Food Habits Black dogfish consume cephalopods, benthic and pelagic crustaceans, euphasiids, schyphozoans, and fishes, including small redfishes (Sebastes). · Reproduction Size at sexual maturity is about 550 mm total length (TL) in male black dogfish and 650 mm TL in females. Litter size is 4-40 in this ovoviviparous species with development of the embryos dependent solely upon yolk reserves. At birth, each pup measures approximately 6 inches (15 cm) total length. The smallest free-swimming specimens to be observed measured 16.5 cm for males and 17.5 cm TL for females. Observations have shown no defined breeding season to exist for the black dogfish. · Predators Potential predators include large fish and sharks residing in the same habitats and depths as the black dogfish. · Parasites A copepod, Albionella fabricii n. sp., has been reported as a parasite on the gills of the black dogfish Centroscyllium fabricii caught off the west coast of Newfoundland. Also, specimens of the mesoparasitic barnacle, Anelasma, were found attached to black dogfish taken from waters off Greenland. Importance to Humans Black dogfish courtesy NOAA Although black dogfish are occasionally taken in large numbers in deepwater bottom trawls, they are not abundant enough to support a commercial fishery. Some may be returned to port and used in processing fish meal. Danger to Humans The black dogfish poses no danger to humans. Conservation The black dogfish is currently not listed by the World Conservation Union (IUCN) as endangered or threatened at this time. The IUCN is a global union of states, governmental agencies, and non-governmental organizations in a partnership that assesses the conservation status of species. Prepared by: George Burgess and Cathy Bester