Arctoidea

Arctoidea Temporal range: Eocene–Holocene,
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Infraclass:	Placentalia
Order:	Carnivora
Suborder:	Caniformia
Clade:	Canoidea
Infraorder:	Arctoidea Flower, 1869
Subclades
†Lonchocyon Ursoidea Mustelida Musteloidea Pan-Pinnipedia Wolsan et al., 2020 †Amphicynodontidae? †Semantoridae Pinnipedimorpha

Arctoidea is an infraorder of mostly carnivorous mammals which include the extinct Hemicyonidae (dog-bears), and the extant Musteloidea (weasels, raccoons, skunks, red pandas), Pinnipedia (seals, sea lions), and Ursidae (bears), found in all continents from the Eocene, 46 million years ago, to the present. The oldest group of the clade is the bears, as their CMAH gene is still intact. The gene became non-functional in the common ancestor of the Mustelida (the musteloids and pinnipeds). Arctoids are caniforms, along with dogs (canids) and extinct bear dogs (Amphicyonidae). The earliest caniforms were superficially similar to martens, which are tree-dwelling mustelids. Together with feliforms, caniforms compose the order Carnivora; sometimes Arctoidea can be considered a separate suborder from Caniformia and a sister taxon to Feliformia.

Phylogeny

The cladogram is based on molecular phylogeny of six genes in Flynn (2005), with the musteloids updated following the multigene analysis of Law et al. (2018).

Caniformia	Amphicyonidae† Canidae Arctoidea Ursoidea Hemicyonidae† Ursidae Mustelida Pinnipedia Enaliarctidae† Phocidae Otariidae Odobenidae Musteloidea Mephitidae Ailuridae Procyonidae Mustelidae