| Arrowhead dogfish | |
|---|---|
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Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Chondrichthyes |
| Order: | Squaliformes |
| Family: | Centrophoridae |
| Genus: | Deania |
| Species: | D. profundorum |
| Binomial name | |
| Deania profundorum (H. M. Smith & Radcliff, 1912) | |
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| Range of arrownose dogfish (in blue) | |
| Synonyms | |
Deania elegans Springer, 1959 | |
The arrowhead dogfish (Deania profundorum) is a small little known deepwater dogfish of the family Centrophoridae.
The arrowhead dogfish has an extremely long angular snout, no anal fin, small first dorsal and long rear dorsal spines, and pitchfork-shaped dermal denticles. The first dorsal fin is short and placed high on the back. This is the smallest of the genus Deania, with a maximum length of only 76 cm.
It is found in the Pacific Ocean around the Philippines, in the Western Atlantic Ocean off of the Carolinas, in the Eastern Atlantic all along Africa's west coast, and in the Indian Ocean off South Africa.
This shark is a little-known deepwater species that lives at depths between 300 and 1,785 m. It is ovoviviparous with five to seven pups per litter. It eats bony fish, squid, and crustaceans.
The Centrophoridae are a family of squaliform sharks. The family contains just two genera and about 15 species. They are sometimes called gulper sharks, but this is also the name of a specific species in the family, Centrophorus granulosus. These are generally deepwater fish. While some, such as the gulper shark C. granulosus, are found worldwide and fished commercially, others are uncommon and little-known. Their usual prey is other fish; some are known to feed on squid, octopus, and shrimp. Some species live on the bottom (benthic), while others are pelagic. They are ovoviviparous, with the female retaining the egg-cases in her body until they hatch.
The lowfin gulper shark is a large deepwater dogfish in the family Centrophoridae.
The smallfin gulper shark is a medium-sized deepwater dogfish in the family Centrophoridae.
The little gulper shark is a small, deepwater dogfish of the family Centrophoridae.
Deania is a genus of long-snouted, deepwater dogfish sharks in the family Centrophoridae.
The birdbeak dogfish is a dogfish shark of the family Centrophoridae found in the Pacific Ocean around Honshū, Japan, southern Australia, New Zealand, and Chile, and in the Atlantic Ocean from Iceland south to the Cape of Good Hope.
The longsnout dogfish is a little-known deepwater dogfish, found in the Atlantic and Indian Oceans from Namibia to Mozambique and in the South Pacific off southern Australia and New Zealand.
The black dogfish is a species of dogfish shark in the family Etmopteridae. It is common over the outer continental shelf and continental slope at depths of 180–2,250 m (590–7,380 ft). Females generally inhabit deeper water than males, and depending on the region, smaller sharks may occur at different depths than larger ones. This species is distributed widely in the Atlantic Ocean, from Greenland and Iceland to Virginia and West Africa in the north, and off southwestern Africa and Argentina in the south. The largest member of its family, the black dogfish, typically measures 60–75 cm (24–30 in) long. It has a stocky, dark brown body that is darker below than above, and bears scattered, minute bioluminescent organs. Its two dorsal fins are preceded by stout spines, and the anal fin is absent.
The granular dogfish, Centroscyllium granulatum, is a little-known, very small dogfish shark of the family Etmopteridae, endemic to the Falkland Islands.
The combtooth dogfish is a little-known, deepwater dogfish shark, named after its teeth that are comb-shaped.
The kitefin shark or seal shark is a species of squaliform shark in the family Dalatiidae, and the type species in its genus. It is found sporadically around the world, usually close to the sea floor at depths of 200–600 m (660–1,970 ft). With a sizable oil-filled liver to maintain neutral buoyancy, this shark is able to cruise slowly through the water while expending little energy. The kitefin shark, the largest luminous vertebrate on record, has a slender body with a very short, blunt snout, large eyes, and thick lips. Its teeth are highly differentiated between the upper and lower jaws, with the upper teeth small and narrow and the lower teeth large, triangular, and serrated. Its typical length is 1.0–1.4 m (3.3–4.6 ft), though examples as long as 5.9 ft (180 cm) have been encountered.
The ornate dogfish is dogfish shark which is not widely known. It is found in deepwater on the continental slopes of the Indian Ocean, the Arabian Sea and the Bay of Bengal, at depths between 520 and 1,260 m. Its length is up to 30 cm, and its reproduction is ovoviviparous.
The whitefin dogfish is a species of deep-sea dogfish shark in the family Etmopteridae. It has only been found in the northwest Pacific Ocean off the southeastern coast of Japan, between the latitudes of 35 and 32°N. It inhabits continental slopes and seamounts at a depth of 320 to 1,100 m. Reproduction is ovoviviparous. It is of no interest to fisheries and almost nothing is known of its biology. The specific epithet ritteri is in honor of Dr. William Emerson Ritter of the University of California.
The Portuguese dogfish or Portuguese shark, is a species of sleeper shark of the family Somniosidae. This globally distributed species has been reported down to a depth of 3,675 m (12,057 ft), making it the deepest-living shark known. It inhabits lower continental slopes and abyssal plains, usually staying near the bottom. Stocky and dark brown in color, the Portuguese dogfish can be distinguished from similar-looking species by the small spines in front of its dorsal fins. Its dermal denticles are also unusual, resembling the scales of a bony fish. This species typically reaches 0.9–1 m (3.0–3.3 ft) in length; sharks in the Mediterranean Sea are much smaller and have distinct depth and food preferences.
The blurred lanternshark is a little-known species of dogfish shark in the family Etmopteridae, found around the world in benthic and pelagic habitats from a depth of 110 m (360 ft) to over 1 km (0.62 mi) down. This shark forms the E. pusillus species group with the smooth lanternshark, which are distinguished from other members of its family by having irregularly arranged, flat-topped dermal denticles that give them a "smooth" appearance. Both species are slender-bodied with long heads, two dorsal fins bearing spines, no anal fins, and light-emitting photophores. The blurred lanternshark is larger, reaching 67 cm (26 in) or more in length. This species feeds on small squid, fishes, and fish eggs, and is ovoviviparous. It has been assessed as of Least Concern by the International Union for Conservation of Nature, because of its wide distribution and lack of threat from fishing pressure.
The smooth lanternshark or slender lanternshark is a species of dogfish shark in the family Etmopteridae, found widely in the Atlantic and Pacific Oceans. It inhabits benthic environments at a depth of 274–1,000 m (899–3,281 ft), and pelagic environments at a depth of 0–708 m (0–2,323 ft). The smooth lanternshark forms a species group with the larger blurred lanternshark, both of which are distinguished from other members of their family by small, irregularly arranged dermal denticles with a truncated shape. This species has a slender, dark brown body with an indistinct black band on the sides over the pelvic fins, and reaches 50 cm (20 in) in length. This slow-growing, ovoviviparous shark feeds on smaller squid, fishes, and fish eggs. Smooth lanternsharks are often caught as bycatch in eastern Atlantic and Japanese commercial fisheries. The International Union for Conservation of Nature (IUCN) has evaluated this species as of Least Concern because of its wide distribution and limited threats.
The velvet belly lanternshark is a species of dogfish shark in the family Etmopteridae. One of the most common deepwater sharks in the northeastern Atlantic Ocean, the velvet belly is found from Iceland and Norway to Gabon and South Africa at a depth of 20–2,490 m (66–8,169 ft). A small shark generally no more than 45 cm (18 in) long, the velvet belly is so named because its black underside is abruptly distinct from the brown coloration on the rest of its body. The body of this species is fairly stout, with a moderately long snout and tail, and very small gill slits. Like other lanternsharks, the velvet belly is bioluminescent, with light-emitting photophores forming a species-specific pattern over its flanks and abdomen. The ventral photophores are thought to function in counter-illumination, which camouflages the shark against predators and prey. The bioluminescent flank markings may play a role in intraspecific communication.
The blackmouth catshark is a species of catshark, and part of the family Scyliorhinidae, common in the northeastern Atlantic Ocean from Iceland to Senegal, including the Mediterranean Sea. It is typically found over the continental slope at depths of 150–1,400 m (490–4,590 ft), on or near muddy bottoms. The youngest sharks generally inhabit shallower water than the older juveniles and adults. This slim-bodied species is characterized by the black interior of its mouth, a marbled pattern of pale-edged brownish saddles or blotches along its back and tail, and a prominent saw-toothed crest of enlarged dermal denticles along the upper edge of its caudal fin. It reaches lengths of 50–79 cm (20–31 in), with sharks in the Atlantic growing larger than those in the Mediterranean.
The deepwater catshark is a catshark of the family Scyliorhinidae, found in the western Atlantic from Delaware Bay to Suriname, and in the eastern Atlantic from Morocco to northwest Africa. An important key factor to understanding these creatures is ageing, many deepwater Apristurus profundorum have poorly calcified vertebrae that lack visible growth bands, and most do not have dorsal fin spines that can be used for ageing. Other methods, such as captive growth and tag-recapture, are also limited in their suitability for deepwater chondrichthyans due to difficulties in the deep sea.
The Pacific spiny dogfish is a common species of the Squalidae (dogfish) family of sharks and are among the most abundant species of sharks in the world. This species is closely related to Squalus acanthias and for many years they were treated as a single species. Recent research, using meristic, morphological and molecular data led to the resurrection of Pacific Spiny Dogfish as a separate species. The American Fisheries Society recommends the common name "Pacific Spiny Dogfish" for Squalus suckleyi over alternatives such as "Spotted Spiny Dogfish" and "North Pacific Spiny Dogfish" and "Spiny Dogfish" for Squalus acanthias.
