Wednesday, March 30, 2011
March 30, 2011 : False Catshark
The false catshark (Pseudotriakis microdon) is a species of ground shark in the family Pseudotriakidae, and the sole member of its genus. It has been reported from a number of locations worldwide, usually at depths of 200-1,500 meters (660-4,900 ft) on the continental slopes. A large, slow-moving shark, it feeds mostly on bony fishes but also takes elasmobranchs and cephalopods, and scavenges off the sea floor. It is one of the few non-lamnoid sharks known to exhibit intrauterine oophagy, in which the developing embryos feed on eggs ovulated by the mother. This species is of minimal interest to fisheries.
The Pacific populations of the false catshark were formerly regarded as a separate species, Pseudotriakis acrales; Leonard Compagno synonymized the two species in 1984 based on a lack of distinguishing characteristics. The closest living relative of the false catshark is the slender smooth-hound (Gollum attenuatus), and some authors place that species in the Pseudotriakidae.
The false catshark is known from scattered locations worldwide, including New York, New Jersey, Cuba, Brazil, Iceland, France, Portugal, Madeira, the Azores, Senegal, Cape Verde, the Aldabra Islands, Japan, Taiwan, Australia, New Zealand, and Hawaii. It is found near the bottom on continental and insular slopes from 173 to 1,890 meters (570-6,100 ft), but occasionally wanders over the continental shelf into shallower water.