Triconodon

Triconodon ("three-coned tooth") is a genus of extinct mammal from the Early Cretaceous of England and France with two known species: T. mordax and T. averianovi. First described in 1859 by Richard Owen, it is the type genus for the order Triconodonta, a group of mammals characterised by their three-cusped (triconodont) molar teeth. Since then, this "simplistic" type of dentition has been understood to be either ancestral for mammals or else to have evolved multiple times, rendering "triconodonts" a paraphyletic or polyphyletic assemblage respectively, but several lineages of "triconodont" mammals do form a natural, monophyletic group, known as Eutriconodonta, of which Triconodon is indeed part of.

Triconodon, therefore, is significant in the understanding of the evolution of mammals by originating the understanding of the "triconodont" grade and eutriconodont clade. Further discoveries on its skeletal anatomy also offer further insights on the palaeobiology of Mesozoic mammals.