Genus

Pseudotriakis

1 species

The false catshark or sofa shark (Pseudotriakis microdon) is a species of ground shark in the family Pseudotriakidae, and the sole member of its genus. It has a worldwide distribution, and has most commonly been recorded close to the bottom over continental and insular slopes, at depths of 500–1,400 m (1,600–4,600 ft). Reaching 3.0 m (9.8 ft) in length, this heavy-bodied shark can be readily identified by its elongated, keel-like first dorsal fin. It has long, narrow eyes and a large mouth filled with numerous tiny teeth. It is usually dark brown in color, though a few are light gray.

With flabby muscles and a large oily liver, the false catshark is a slow-moving predator and scavenger of a variety of fishes and invertebrates. It has a viviparous mode of reproduction, featuring an unusual form of oophagy in which the developing embryos consume ova or egg fragments released by the mother and use the yolk material to replenish their external yolk sacs for later use. This species typically gives birth to two pups at a time. The International Union for Conservation of Nature (IUCN) has assessed the conservation status of the false catshark as Least-concern. While neither targeted by fisheries nor commercially valuable, it is caught incidentally by longlines and bottom trawls, and its low reproductive rate may render it susceptible to population depletion.

Though rarely encountered, the false catshark has been caught from locations scattered around the world, indicating a wide circumglobal distribution. In the western Atlantic, it has been reported from Canada, the United States, Cuba, and Brazil. In the eastern Atlantic, it is known from the waters of Iceland, France, Portugal, and Senegal, as well as the islands of Madeira, the Azores, the Canaries, and Cape Verde. Records from the Indian Ocean have come from off Madagascar, the Aldabra Group, Mauritius, Indonesia, and Australia. In the Pacific Ocean, it has been documented from Japan, Taiwan, Indonesia, the Coral Sea, New Zealand, and the Hawaiian Islands.

Inhabiting continental and insular slopes, the false catshark mostly occurs between the depths of 500 and 1,400 m (1,600 and 4,600 ft), though it has been recorded as deep as 1,900 m (6,200 ft). Individuals occasionally wander into relatively shallower waters over the continental shelf, perhaps following submarine canyons or suffering from an abnormal condition. The false catshark generally swims close to the sea floor and has been found at seamounts, troughs, and deepwater reefs.

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The false catshark or sofa shark (Pseudotriakis microdon) is a species of ground shark in the family Pseudotriakidae, and the sole member of its genus. It has a worldwide distribution, and has most commonly been recorded close to the bottom over continental and insular slopes, at depths of 500–1,400 m (1,600–4,600 ft). Reaching 3.0 m (9.8 ft) in length, this heavy-bodied shark can be readily identified by its elongated, keel-like first dorsal fin. It has long, narrow eyes and a large mouth filled with numerous tiny teeth. It is usually dark brown in color, though a few are light gray.

With flabby muscles and a large oily liver, the false catshark is a slow-moving predator and scavenger of a variety of fishes and invertebrates. It has a viviparous mode of reproduction, featuring an unusual form of oophagy in which the developing embryos consume ova or egg fragments released by the mother and use the yolk material to replenish their external yolk sacs for later use. This species typically gives birth to two pups at a time. The International Union for Conservation of Nature (IUCN) has assessed the conservation status of the false catshark as Least-concern. While neither targeted by fisheries nor commercially valuable, it is caught incidentally by longlines and bottom trawls, and its low reproductive rate may render it susceptible to population depletion.

Though rarely encountered, the false catshark has been caught from locations scattered around the world, indicating a wide circumglobal distribution. In the western Atlantic, it has been reported from Canada, the United States, Cuba, and Brazil. In the eastern Atlantic, it is known from the waters of Iceland, France, Portugal, and Senegal, as well as the islands of Madeira, the Azores, the Canaries, and Cape Verde. Records from the Indian Ocean have come from off Madagascar, the Aldabra Group, Mauritius, Indonesia, and Australia. In the Pacific Ocean, it has been documented from Japan, Taiwan, Indonesia, the Coral Sea, New Zealand, and the Hawaiian Islands.

Inhabiting continental and insular slopes, the false catshark mostly occurs between the depths of 500 and 1,400 m (1,600 and 4,600 ft), though it has been recorded as deep as 1,900 m (6,200 ft). Individuals occasionally wander into relatively shallower waters over the continental shelf, perhaps following submarine canyons or suffering from an abnormal condition. The false catshark generally swims close to the sea floor and has been found at seamounts, troughs, and deepwater reefs.

show less