houndshark

{{Short description|Family of sharks}}

{{Automatic taxobox

| name = Houndsharks

| fossil_range = {{Fossil range|Cenomanian|Recent}}

| image = Leopard shark in kelp.jpg

| image_caption = Leopard shark (Triakis semifasciata)

| taxon = Triakidae

| authority = J. E. Gray, 1851

| subdivision_ranks = Subfamilies and genera

| subdivision_ref = {{Cof family|family=Triakidae|access-date=27 October 2024}}

| subdivision = see text

}}

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 {{cvt|37|to|220|cm|ft}} 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.{{FishBase_family|family=Triakidae|year=2009|month=January}}

Fossil records of this group date back to the Cenomanian.{{Cite journal |last=Popov |first=E. V. |last2=Lapkin |first2=A. V. |date=2000 |title=A New Shark Species of the Genus Galeorhinus (Chondrichthyes, Triakidae) from the Cenomanian of the Lower Volga River Basin |url=https://www.researchgate.net/profile/Evgeny-Popov-3/publication/260530315_A_New_Shark_Species_of_the_Genus_Galeorhinus_Chondrichthyes_Triakidae_from_the_Cenomanian_of_the_Lower_Volga_River_Basin/links/0c960531823bc294c6000000/A-New-Shark-Species-of-the-Genus-Galeorhinus-Chondrichthyes-Triakidae-from-the-Cenomanian-of-the-Lower-Volga-River-Basin.pdf |journal=Paleontological Journal |volume=34 |issue=4 |pages=435–438}}