Which bear is the only member of the genus Tremarctos?

The only living bear in the genus Tremarctos is the spectacled bear, also called the Andean bear.

Its scientific name is Tremarctos ornatus. The genus name refers to a distinctive opening in the upper-arm bone, while ornatus means “decorated” in Latin, reflecting the pale markings on the face and chest. Those markings can resemble spectacles, although their shape varies between individuals.

Tremarctos belongs to the short-faced-bear subfamily, Tremarctinae. Several related genera once lived in the Americas, including the giant short-faced bear Arctodus and the South American Arctotherium, but those lineages disappeared during the late Pleistocene. The Florida spectacled bear, Tremarctos floridanus, was another member of the genus but is extinct, leaving the spectacled bear as its sole living species.

A common mix-up is confusing “only member of the genus” with “only member of the subfamily.” The spectacled bear is the only living Tremarctos species and the last surviving tremarctine bear. It is also the only bear species native to South America, living mainly in the Andes.