Mixtotherium is an extinct genus of Palaeogene artiodactyls belonging to the monotypic family Mixtotheriidae. Known informally as mixtotheriids or mixtotheres, these artiodactyls were endemic to weste
Mixtotherium priscum skull
The Mixtotheriidae is thought to be closely related to the Cainotheriidae, including Cainotherium (skeleton at Natural History Museum of Basel)
Rock hyrax (Procavia capensis) skull, National Museum of Natural History. The mandibular rami of hyraxes are wide similar to those of Mixtotherium.
M. priscum mandible, Natural History Museum of Basel
Amphimerycidae is an extinct family of artiodactyls that was endemic to western Europe and lived from the Middle Eocene to the Early Oligocene. With a taxonomic history extending as far back as 1804,
Mixtotherium
…Cainotheriidae, Robiacinidae, Anoplotheriidae, and Mixtotheriidae formed a clade that was the sister group to the Ruminantia while Tylopoda, along with the Amphimerycidae and Xiphodontidae split earlier in the tree. The phylogenetic tree published in the article and another work about the cainotherioids is outlined below…
lossy page 1 Amphimeryx murinus Montmatre Paris France.tif
Drawing of a mandible of "Anoplotherium murinum" (= Amphimeryx murinus), 1822)
Because of some similar anatomical traits of the amphimerycids to those of ruminants (like the Java mouse-deer (Tragulus javanicus), pictured), they were previously considered ruminants by biologists. Today, their evolutionary relationship to ruminants and other artiodactyls proves unclear.
Pseudamphimeryx renevieri mandible, Natural History Museum of Basel