Houndshark
The Triakidae or houndsharks are a family of ground sharks, consisting of about 40 species in nine genera. In some classifications, the family is split into two subfamilies, with the genera Mustelus, Scylliogaleus and Triakis in the subfamily Triakinae, and the remainders in the subfamily Galeorhininae.
Houndsharks are distinguished by possessing two large, spineless dorsal fins, an anal fin and oval eyes with nictitating eyelids. They are small to medium in size, ranging from in adult length. They are found throughout the world in warm and temperate waters, where they feed on small fish and invertebrates on the seabed and in midwater.
Fossil records of this group date back to the Cenomanian.
Genera
Houndsharks are classified into subfamilies and genera as follows:- Galeorhininae Gill, 1862
- * Furgaleus Whitley, 1951
- * Galeorhinus Blainville, 1816
- * Gogolia Compagno, 1973
- * Hemitriakis Herre, 1923
- * Hypogaleus J. L. B. Smith, 1957
- * Iago Compagno & Springer, 1971
- Triakinae Gray, 1851
- * Mustelus H. F. Linck, 1790
- * Scylliogaleus Boulenger, 1902
- * Triakis J. P. Müller & Henle, 1839
- ?†Archaeotriakis Case, 1978
- †Gomphogaleus Adnet & Cappetta, 2008
- †Kallodentis Engelbrecht, Mörs, Reguero & Kriwet, 2017
- †Khouribgaleus Noubhani & Cappetta, 1997
- †Meridiogaleus Engelbrecht, Mörs, Reguero & Kriwet, 2017
- †Pachygaleus Cappeta, 1992
- †Palaeogaleus Gurr, 1962
- †Palaeotriakis Guinot, Underwood, Cappetta & Ward, 2013
- †Paratriakis Herman, 1977
- †Rhaibodus Böhm, 1926
- †Squatigaleus Cappetta, 1989
- †Xystrogaleus Adnet, 2006