Cainotherium renggeri (Bravard 1828, 1835; 30cm in length; Eocene to Early Miocene) was and is considered a rabbit-sized artiodactyl not far from the odd-toed ungulates, like the similarly-sharp-clawed Chalicotherium.
Note that a derived artiodactyl, Ancodus (Fig. 2) had five fingers, so one wonders if Cainotherium likewise had five.
Bravard A 1835. Monographie du Cainotherium, Levrault, Paris, 1835.
Heizmann EPJ 1999. Family Cainotheriidae, in : Rössner G.E., Heis- sig K. (éds), The Miocene Land Mammals of Europe, Pfeil, 1999, pp. 217–220.