In mirorder Ferae

The common feature for members of this mirorder is ossified tentorium cerebelli and the fusion of the scaphoid and lunate bones in the wrist.^[11][12]

forefoot of Vulpavus profectus

forefoot of
Thinocyon medius

forefoot of Patriofelis ferox

In clade Pan-Carnivora

The common feature for members of clade Pan-Carnivora is the presence of the carnassial teeth. This feature allows distinguishing the Carnivoramorpha, Oxyaenodonta and Hyaenodonta from the other carnivorous placental mammals.^[11] However, these mammals are distinguished between them self based on the position of the carnassial teeth and the number of molars. The carnassial teeth of the Carnivoramorpha are located in P₄ and m₁, in Oxyaenodonta are M₁ and m₂, and in Hyaenodonta are M₂ and m₃. This appears to be a case of a possible evolutionary convergent adaptation toward similar diet.^[11]

Comparison of carnassial teeth of a carnivoran (wolf), a hyaenodontid (Hyaenodon) and an oxyaenid (Oxyaena)

lower jaws of Wyolestes dioctes

lower jaw of Simidectes medius

Sister groups to Ferae and position of pangolins and creodonts

According to recent studies (reflected in the diagram below), the closest living relatives of Ferae are members of mirorder Euungulata (group of mammals which includes order Perissodactyla and Artiodactyla).^[13][14]

An alternate phylogeny holds that the closest relatives to the Ferae are the Perissodactyla and Chiroptera (bats), not Artiodactyla.^[15] Ferae together with Perissodactyla has been called Zooamata. Ferae, Perissodactyla, and Chiroptera together has been called Pegasoferae. Subsequent molecular studies have generally failed to support the proposal.^{[16][17][18][19][20]}

Pangolins were long thought to be the closest relatives of aardvark and xenarthrans (armadillos, anteaters, and sloths), forming to the now obsolete order Edentata. Research based on immunodiffusion technique^[21] and comparison of protein and DNA sequences^[22][23][24] revealed the close relationships between pangolins and carnivorans, with whom they also share a few unusual derived morphological and anatomical traits, such as the ossified tentorium cerebelli and the fusion of the scaphoid and lunate bones in the wrist. The last common ancestor of extant Ferae is supposed to have diversified c. 79.47 million years ago.^[1]

While there has been strong support in the inclusion of order Creodonta into Ferae, they were usually recovered as sister taxon to Carnivora.^[9] The Halliday et al. (2015) phylogenetic analysis of hundreds of morphological characters of Paleocene placentals found instead that creodonts might be the sister group to Pholidotamorpha (pangolins and their stem-relatives).^[25] However, recent studies have shown that Creodonta is an invalid polyphyletic taxon. Members of this group are part of clade Pan-Carnivora and sister taxa to Carnivoramorpha (carnivorans and their stem-relatives). They are split in two groups: order Oxyaenodonta on one side and order Hyaenodonta plus its stem-relatives (family Wyolestidae and genera Altacreodus, Simidectes and Tinerhodon) on the other.^{[26][27][28][29][30]}

Taxonomy

Traditional classification:

Revised classification:

Clade: Ferae (Linnaeus, 1758) Order: Carnivora (Bowdich, 1821) (carnivorans) Order: Cimolesta (McKenna, 1975) [a group with pangolins as its members at that time] Order: †Creodonta (Cope, 1875) (false carnivorans)

Mirorder: Ferae (Linnaeus, 1758) Clade: Pan-Carnivora (Flynn, Wyss & Wolsan, 2020)[31] Clade: Carnivoramorpha (Wyss & Flynn, 1993) (carnivorans and stem-relatives) Order: †Hyaenodonta (Van Valen, 1967) Order: †Oxyaenodonta (Van Valen, 1971) Family: †Oxyaenidae (Cope, 1877) Family: †Wyolestidae (Gingerich, 1981) Genus: †Simidectes (Stock, 1933) (unranked): †Altacreodus/Tinerhodon clade Genus: †Altacreodus (Fox, 2015) Genus: †Tinerhodon (Gheerbrant, 1995) Clade: Pholidotamorpha (Gaudin, 2009) Order: Pholidota (Weber, 1904) (pangolins) Order: †Palaeanodonta (Matthew, 1918) (stem-pangolins)