Tortonian genus extinctions

Desmostylus is an extinct genus of herbivorous mammal of the family Desmostylidae living from the Chattian stage of the Late Oligocene subepoch through the Late Miocene subepoch (28.4 mya–7.250 Mya) and in existence for approximately .

The genus Leptocyon (Greek: leptos slender + cyon dog) includes 11 species and is the oldest known canine. They were small and weighed around . They first appeared in North America around 34 million years ago in the Oligocene, at the same time as the Borophaginae, with whom they share features, indicating that these were two sister groups. Borophaginae skull and dentition were designed for a powerful killing bite compared with the Leptocyon which were designed for snatching small, fast-moving prey. The species L. delicatus is the smallest canid to have existed. At the close of their genus 9 mi

Amphechinus is an extinct genus of hedgehog of the family Erinaceidae, which lived in Asia and Europe during the Oligocene and in North America, Africa, Asia and Europe during the Miocene. The genus contains at least 14 species. It is classified in the subfamily Erinaceinae and in the family Erinaceidae.

Maximucinus is an extinct genus of thylacinid that lived during the Middle Miocene in what is now Queensland, Australia. It is known only a second upper molar found at the Riversleigh World Heritage Area. It was the largest thylacinid of its time, attaining a body size of 18 kg (40 lbs). The genus is monotypic, containing only one species, Maximucinus muirheadae.