| Hyainailouridae | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | †Hyaenodonta |
| Family: | †Hyainailouridae |
| Type species | |
| †Hyainailouros sulzeri Biedermann, 1863 | |
| Species | |
Hyainailouridae is a family of extinct predatory mammals belonging to Hyaenodonta, a clade of creodonts. Fossils have been found in Asia, Africa, and Europe. Hyainailouridae used to be considered a subfamily of Hyaenodontidae, but cladistic study by Sole et al., (2013, 2015) treats it as a distinct family. Two subfamilies are recognized, Apterodontinae and Hyainailourinae. Hyainailourids are characterized by long skulls, slender jaws, slim bodies, and a plantigrade stance. They generally ranged in size from 30 to 140 cm at the shoulder. While some measured as much as 1.4 m high at the shoulder with head-body length up to 3.2 m and weighed up to 1,500 kg, most were in the 5–15 kg range, equivalent to a mid-sized dog. The anatomy of their skulls show that they had a particularly acute sense of smell, while their teeth were adapted for shearing, rather than crushing. At least one hyainailourid lineage, Apterodontinae, was specialised for aquatic, otter-like habits.