Amphicyonidae

Mounted skeleton of Amphicyon longiramus, from here.

Belongs within: Carnivora.

The Amphicyonidae, commonly called bear-dogs, are a group of relatively large carnivorans of somewhat uncertain affinities known from the late Oligocene to late Miocene of Eurasia, Africa and North America (Savage 1978). They are generally agreed to have had caniform affinities, but different authors have placed them closer to dogs, bears or to the Arctoidea clade as a whole (Flynn et al. 1988). The largest amphicyonids are estimated to have reached about 600 kg in weight.

Characters (from Flynn et al. 1988): Skeleton massive; tail long; feet plantigrade, pentadactyl. Skull elongate; premolars simple, low-crowned, elongated, often separated by diastemata; M³ originally present; upper molars with strong lingual cingulum nearly symmetrically disposed around protocone; upper carnassial with anteriorly placed protocone; M₂ with paraconid; lower molar talonids with low entoconid, hypoconid a longitudinal crest more centrally located on talonid. Auditory bulla with small entotympanic, either unossified or consisting mostly of carotid canal; ectotympanic just covering promontorium, not extending posterior to mastoid process. External auditory meatus inflated by extension of hypotympanic sinus.

<==Amphicyonidae [Amphicyoninae]
    |--Afrocyon burolleti S78
    |--Temnocyon obtusidens V91
    |--Cynelos caroniavorus FNT88, V91
    |--Ischyrocyon gidleyi V91
    |--Hecubides S78
    |    |--H. euryodon S78
    |    `--H. macrodon S78
    |--Daphoenus Lartet 1836 [Daphoenidae, Daphoeninae] D07
    |    |--D. hartshornianus V91
    |    |--D. lambei D07
    |    |--D. nebrascensis D07
    |    `--D. vetus D07
    `--Amphicyon Lartet 1836 D07
         |--A. giganteus D07
         |--‘Mustela’ incerta K54
         |--A. longiramus D07
         |--A. major D07
         `--A. tairumensis DW04

*Type species of generic name indicated

REFERENCES

[DW04] Deng T., Wang X., Ni X. & Liu L. 2004. Sequence of the Cenozoic mammalian faunas of the Linxia Basin in Gansu, China. Acta Geologica Sinica (English Edition) 78 (1): 8–14.

[D07] Dixon, D. 2007. The Complete Illustrated Encyclopedia of Dinosaurs & Prehistoric Creatures. Hermes House: London.

[FNT88] Flynn, J. J., N. A. Neff & R. H. Tedford. 1988. Phylogeny of the Carnivora. In: Benton, M. J. (ed.) The Phylogeny and Classification of the Tetrapods vol. 2. Mammals pp. 73–116. Clarendon Press: Oxford.

[K54] Kurtén, B. 1954. The type collection of Ictitherium robustum (Gervais, ex Nordmann) and the radiation of the ictitheres. Acta Zoologica Fennica 86: 1–26.

[S78] Savage, R. J. G. 1978. Carnivora. In: Maglio, V. J., & H. B. S. Cooke (eds) Evolution of African Mammals pp. 249–267. Harvard University Press: Cambridge (Massachusetts).

[V91] Valkenburgh, B. van. 1991. Iterative evolution of hypercarnivory in canids (Mammalia: Carnivora): evolutionary interactions among sympatric predators. Paleobiology 17 (4): 340–362.

Last updated: 9 August 2018.