DNA research has reorganised the picture of mammalian evolution. Paenungulates and tubulidentates are seen as afrotherians, and no longer seen as closely related to the laurasiatherian perissodactyls, artiodactyls, and cetaceans, implying that hooves were acquired independently (i.e. were analogous) by at least two different mammalian lineages, once in the Afrotheria and once in the Laurasiatheria. Condylarthra itself, therefore, is polyphyletic: the several condylarth groups are not closely related to each other at all. Indeed, Condylarthra is sometimes regarded as a 'wastebasket' taxon. True relationships remain in many cases unresolved. In addition to meridiungulates and living ungulates, a condylarthran ancestry has been proposed for several other extinct groups of mammals, including Mesonychia and Dinocerata. Taxonomy Family Arctocyonidae (possibly polyphyletic assemblage) Genus Arctocyon Genus Chriacus Family Periptychidae Genus Ectoconus Genus Oxyacodon Family Hyopsodontidae (now established as within Perissodactyla) Subfamily Tricuspiodontinae Genus Litomylus Genus Paratricuspiodon Genus Tricuspiodon Genus Aletodon Genus Decoredon Genus Dipavali Genus Dorraletes Genus Haplaletes Genus Haplomylus Genus Hyopsodus Genus Louisina Genus Microhyus Genus Midiagnus Genus Oxyprimus Genus Palasiodon Genus Paschatherium Genus Utemylus Genus Yuodon Family Mioclaenidae Family Phenacodontidae (established as stem-Perissodactyla) Subfamily Meniscotheriinae Genus Ectocion Genus Meniscotherium Genus Almogaver Genus Copecion Genus Eodesmatodon Genus Phenacodus Family Pleuraspidotheriidae Genus Hilalia Genus Orthaspidotherium Genus Parabunodon Genus Pleuraspidotherium Family Didolodontidae (stem-Meridiungulata) Family Sparnotheriodontidae? (Litopterna) Genus Tingamarra? (non-descript therian mammal) Genus Protungulatum (either non-placental eutherian or basal artiodactyl). Genus Kharmerungulatum (a zhelestid) See also Evolution of mammals List of prehistoric mammals Notes References External links Obsolete mammal taxa