The finback catsharks are a small family, the Proscylliidae, of ground sharks. They can be found in warm seas worldwide and are often the most numerous and common shark in tropical regions. They are generally less than 1 m in length, and are slow-moving predators that feed on bony fish and small invertebrates. Although some bear live young, the majority lay eggs with almost fully developed young; these egg cases, known as "mermaid's purses", are unique in appearance to each species.

Taxonomy

Genus Proscyllium Hilgendorf 1904

Genus Eridacnis H. M. Smith, 1913

Genus Ctenacis Compagno, 1973

The harlequin catshark (Ctenacis fehlmanni) has some unique characteristics that set it aside from the others. Its large mouth, small teeth and large pharynx with gill raker papillae make it unique among the family Proscyllidae. They are found in the tropical outer continental shelves of the western Indian Ocean, off the coast of Somalia, feeding on very small invertebrates. They are oviparous, laying paired eggs in which their embryos feed solely on yolk.

Distribution

Found primarily along the continental shelves, these species are scattered throughout the world. They have been documented and seen primarily in: Japan, Myanmar, the Philippines, South Africa, Mozambique, Tanzania, and Somalia.

Lifecycle

Reproduction

Within this family, species are either oviparous or ovoviviparous. Oviparous refers to many benthic sharks that lay their eggs on the seafloor and attach them to a substrate. The eggs have a hard and leathery shell surrounding them to serve as protection. The eggs feed solely on the yolk present within the casing. Other species within this family are ovoviviparous. Ovoviviparous sharks give birth to live young.

Human interactions

This family of small ground sharks is not targeted by humans for any fishing or food purposes. Although not endangered or threatened, these species are negatively impacted by fisheries as a result of bycatch. The shrimping industry has affected them the most.