Deep water catshark

10/26/2016

Deepwater catshark, Apristurus profundorum. From plate 5 of Oceanic Ichthyology by G. Brown Goode and Tarleton H. Bean, published 1896.

The genus Apristurus is made up of at least 32 described species and a large number of species that are potentially undescribed. Our featured shark, the deep water catshark (Apristurus profundorum), is only known from ONE holotype, an adolescent male.

This Apristurus profundorum holotype was a 51 cm total length (TL) adolescent male caught off Delaware Bay, USA in the Northwest Atlantic at ~1,490 m (~ 4888 ft) depth. Adults may get relatively large compared to the other Apristurus species, which tend to be relatively small.

Generally a sluggish genus, these sharks live on or near the bottom on the upper continental slope. Their preferred diet includes crustaceans, squids and small fishes. Little is known about their reproduction, although it is assumed they are oviparous with one egg per oviduct. As with other sharks whose eggs have coiled tendrils, these tendrils help attach the egg cases to sturdy areas.

This species gets commonly confused with Apristurus manis, and therefore much is still unknown. While some deepwater Chondrichthyans get captured as bycatch in deepwater fisheries, it is unknown if this species is subject to that. The IUCN doesn't have enough information to assess them beyond Data Deficient (DD).

ever heard of these sharks before?

glossary

Bycatch: The part of a fishery’s catch that is made up of non-target species.
Continental slope: The steep slope from a continental shelf to the ocean floor; usually around 20 km (12.4 miles) wide and made up of mud and silt substrate. It is an ideal area for deepsea fishing.
Crustaceans: Group of animals with a hard exoskeleton, jointed legs and segmented body.
Generas: Plural form of genus.
Genus: A group of organisms ranking above a species and below a family.
Holotype: A single specimen used in the original description of a species.
IUCN: International Union for Conservation of Nature.
Oviduct: The tube that links the ovary to the uterus. In female mammals this passageway is known as the uterine tube or fallopian tube.

Oviparity/oviparous: Where adult Chondrichthyans lay eggcases (also known as ‘mermaid’s purses) and the baby develops inside the egg before hatching.