Squalidae

Last updated

Dogfish sharks
Temporal range: Upper Cretaceous–Recent
Squalus acanthias.jpg
Spiny dogfish, Squalus acanthias
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Subdivision: Selachimorpha
Order: Squaliformes
Family: Squalidae
Bonaparte, 1834
Genera

Squalidae, more commonly known as dogfish, dog sharks, or spiny dogfish, [2] are one of several families of sharks categorized under Squaliformes, making it the second largest order of sharks, numbering 119 species across 7 families. [3] Having earned their name after a group of fishermen reportedly observed the species chasing down smaller fish in dog-like packs, [4] dogfish have slender, streamlined bodies, usually more compact in comparison to other species, and a pointed snout. Dogfish likewise have two dorsal fins, each with smooth spines, but no anal fin, and their skin is generally rough to the touch. [1] As the species reaches adulthood, males usually measure a maximum of 100 cm (39 inches), while females typically measure 125 cm (49 inches) long. The species therefore exhibits female-dominant sexual dimorphism.

Contents

Dogfish sharks have slate-grey or grey-brown skin with white dots that becomes paler (almost white) around the belly region. These sharks are characterized by teeth in upper and lower jaws similar in size; a caudal peduncle with lateral keels; the upper precaudal pit usually is present; and the caudal fin is without a subterminal notch.

They are carnivorous, principally preying upon organisms smaller than themselves. Some of their prey include herring, mackerel, and capelin. In special cases, they may consume jellyfish and squid. Even at a young age, spiny dogfish pups may hunt fish two or three times their size.[ citation needed ] Unlike virtually all other shark species, dogfish sharks possess venom which coats their dorsal spines; this venom is mildly toxic to humans and would be harmful if the shark were to be mishandled. The livers and stomachs of the Squalidae contain the compound squalamine, which possesses the property of reduction of small blood vessel growth in humans. [5] Dogfish sharks use their strong jaw and sharp teeth to consume their prey.

The spiny dogfish has broken several records in the areas of migration and gestation. This shark tends to be a highly migratory species: one shark was recorded as travelling 8,000 km (5,000 miles) after being tagged in Washington state, United States, and found again later in Japan. In addition to its long distance migration, the spiny shark holds the record for longest gestation period of any other vertebrate at 22–24 months. Females produce eggs and give birth to live young that measure to be 20–33 cm (8–13 inches).

Taxonomy

Dogfish are scientifically classified as the Squalidae family, categorized under the Squaliform order, which encompasses seven families in total, including Squalidae. The Squalidae family itself contains two separate genera: Cirrhigaleus and Squalus , numbering 37 species between the two.

Squalidae Classification
Order: Squaliformes

Family: Within Squaliforme order, there are seven families

Genus: Within the Squalidae dogshark family, are two known genera

for a full list of species in each genera: list of sharks
Squalus acanthias, or the spiny dogfish (adult), with grey-brown body coloration, decorated by evenly-spaced, small, white dots, and lighter underbelly. Squalus acanthias2.jpg
Squalus acanthias , or the spiny dogfish (adult), with grey-brown body coloration, decorated by evenly-spaced, small, white dots, and lighter underbelly.
Cirrhigaleus barbifer, or the Mandarin dogfish (adult), pictured with grey-brown body coloration, decorated in an array of speckled black dots, with a lighter underbelly, and elongated nasal barbels. Mandarin dogfish2.jpg
Cirrhigaleus barbifer , or the Mandarin dogfish (adult), pictured with grey-brown body coloration, decorated in an array of speckled black dots, with a lighter underbelly, and elongated nasal barbels.

Related Research Articles

<span class="mw-page-title-main">Squaliformes</span> Order of fishes

The Squaliformes are an order of sharks that includes about 126 species in seven families.

Dogfish may refer to:

<span class="mw-page-title-main">Spiny dogfish</span> Species of shark

The spiny dogfish, spurdog, mud shark, or piked dogfish is one of the best known species of the Squalidae (dogfish) family of sharks, which is part of the Squaliformes order.

<span class="mw-page-title-main">Little gulper shark</span> Species of shark

The little gulper shark is a small, deepwater dogfish of the family Centrophoridae.

Squalus is a genus of dogfish sharks in the family Squalidae. Commonly known as spurdogs, these sharks are characterized by smooth dorsal fin spines, teeth in upper and lower jaws similar in size, caudal peduncle with lateral keels; upper precaudal pit usually present, and caudal fin without subterminal notch. In spurdogs, the hyomandibula is oriented at a right angle to the neurocranium, while in other sharks, the hyomandibula runs more parallel to the body. This led some to think that the upper jaw of Squalus would not be as protractile as the jaws of other sharks. However, a study that compared different jaw suspension types in sharks showed that this is not the case and that Squalus is quite capable of protruding its upper jaw during feeding.

<span class="mw-page-title-main">Mandarin dogfish</span> Species of shark

The mandarin dogfish is a dogfish, a member of the family Squalidae in the order Squaliformes. It is found at depths of 140–650 metres (460–2,130 ft) off southern Japan, Taiwan, and Indonesia. Populations off Australia and New Zealand were formerly included in this species, but in 2007 these were assigned to a new species, the southern mandarin dogfish. It is not clear which of these species is involved in other populations from the tropical West Pacific.

<span class="mw-page-title-main">Cuban dogfish</span> Species of shark

The Cuban dogfish is a dogfish, a member of the family Squalidae in the order Squaliformes.

<i>Cirrhigaleus</i> Genus of sharks

Cirrhigaleus is a genus of sharks in the Squalidae (dogfish) family, which is part of the Squaliformes order.

<span class="mw-page-title-main">Blacktailed spurdog</span> Species of shark

The blacktailed spurdog is a dogfish, a member of the family Squalidae, found around New Caledonia in the central Pacific Ocean, at depths from 320 to 320 m. Its length is up to 75 cm.

<span class="mw-page-title-main">Shortspine spurdog</span> Species of shark

The shortspine spurdog is a dogfish, a member of the family Squalidae, found on continental shelves off Japan in temperate waters, from the surface to 950 m. Its length is up to 75 cm.

Squalus crassispinus, the fatspine spurdog, is a dogfish of the family Squalidae, found on the continental shelf off the northern coast of Western Australia, at depths of 180 to 200 metres. The length of the longest male specimen measured is 56 centimetres (22 in).

Squalus nasutus, the western longnose spurdog, is a dogfish of the family Squalidae, found on the continental shelf off the northwest and southwest coasts of Western Australia, at depths between 300 and 510 m. Its length is at least 55 cm.

<span class="mw-page-title-main">Southern Mandarin dogfish</span> Species of shark

The southern Mandarin dogfish is a species of Mandarin dogfish shark in the genus Cirrhigaleus. It was distinguished from Cirrhigaleus barbifer, which lives in the North Pacific, on an expedition in the coral reefs near Australia in 2007. It is now known to live in the temperate waters in south-eastern Australia and from the Bay of Plenty region in New Zealand, at depths of 146–640 metres.

The Taiwan spurdog is a species of shark in the genus Squalus. It was accidentally found in Taiwan's Tashi fish market by William Toby White and a colleague of the CSIRO in Hobart, Australia. They named it S. formosus. It has also be recorded from the coast of Japan, near Kyushu and Shikoku.

The Philippine spurdog or Indonesian greeneye spurdog, is a relatively large species of dogfish shark native to waters off the coast of Australia, the Philippines, and Indonesia. The species was identified in 1912 from a specimen caught off the coast of Luzon Island, and has been both bycatch and a targeted species in fisheries since. Its taxonomy is complex, having been renamed in 1931, being misidentified as a type of shortspine spurdog, then being revived as a species in 2007.

<span class="mw-page-title-main">Squalomorphii</span> Superorder of cartilaginous fishes

Squalomorphii is a superorder of cartilaginous fishes, generally characterized by lacking traits such as an anal fin, nictitating membrane, or suborbital shelves in the cranium. Squalomorphii sharks are also called squalea, or squalean sharks. There are about 163 living species in 11 families. Squalean sharks are divided into four orders: the Hexanchiformes, Squaliformes, Squatiniformes, and Pristiophoriformes.

<span class="mw-page-title-main">Pacific spiny dogfish</span> Species of shark

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.

The greeneye spurdog is a species of dogfish described in 2007. It is a member of the family Squalidae, found off the coast of southeastern Australia. The length of the longest specimen measured is 85.6 cm (33.7 in). It was considered conspecific with the shortspine spurdog.

The northern spiny dogfish, also known as the brown dogfish, grey spiny dogfish or Griffin's dogfish, is a marine species of the family Squalidae, found off New Zealand's North Island. The length of the longest specimen measured is 89.9 cm (35.4 in).

The Kermadec spiny dogfish is a dogfish described in 2007. It is a member of the family Squalidae, found off the Kermadec Islands. The length of the longest specimen measured is 68.1 cm (26.8 in).

References

  1. 1 2 Froese, Rainer, and Daniel Pauly, eds. (2009). "Squalidae" in FishBase . January 2009 version.
  2. "Squalidae". Integrated Taxonomic Information System . Retrieved 16 November 2013.
  3. Straube, N.; Li, C.; Claes, J.M. (2015). "Molecular phylogeny of Squaliformes and first occurrence of bioluminescence in sharks". BMC Evolutionary Biology. 15 (162). doi: 10.1186/s12862-015-0446-6 . PMC   4537554 .
  4. "Spiny Dogfish". Oceana. Retrieved 2019-04-12.
  5. "From the Belly of a Shark, a Cancer Cure?". National Geographic. Vol. 193, no. 6. June 1998. p. 202. Retrieved 2 January 2023.
  6. de F. L. Viana, S. T.; Lisher, M. W.; de Carvalho, M. R. (2018). "Two new species of short-snouted dogfish sharks of the genus Squalus Linnaeus, 1758, from southern Africa (Chondrichthyes: Squaliformes: Squalidae)". Marine Biodiversity. 48: 1787–1814. doi:10.1007/s12526-017-0673-8.
  7. Froese, R.; Pauly, D. "Genus: Squalus". fishbase.org. FishBase.
  8. Ebert, D. A. (2010). "Resurrection and redescription of Squalus suckleyi (Girard, 1854) from the North Pacific, with comments on the Squalus acanthias subgroup (Squaliformes: Squalidae)". Zootaxa. 2612 (1): 22–40.
  9. White, W. T.; Last, P. R.; Stevens., J. D. (2007). "Cirrhigaleus australis n. sp., a new Mandarin dogfish (Squaliformes: Squalidae) from the south-west Pacific". Zootaxa. 1560 (1): 19–30. doi:10.11646/ZOOTAXA.1560.1.2.
  10. Froese, R.; Pauly, D. "Genus: Cirrhigaleus". fishbase.org. FishBase.
  11. Tanaka, Shigeho (1917). "Three new species from Japan". Zoology. 29: 225–226.

Further reading