The Evolution of Man
 
Tetrapoda
Basal Tetrapoda
Reptilomorpha
Lepospondyli
 
Reptilia/Amniota
Gephyrostegus
 
Archosauromorpha
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Turtle Pareiasaur clade
Lanthanosuchia
Owenettidae
Lepidosauriformes
Lepidosauria
Tritosauria
Fenestrasauria • Pterosauria
Protosquamata
Squamata
 
Chaoyangodens lii in situ

Chaoyangodens lii (Hou and Meng 2014; early Cretaceous, 120mya) was considered a eutriconodont mammal with a reduced post-canine tooth formula and five incisors. Here it nests in the monotreme clade between Brasilitherium and Akidolestes. The teeth are large for the skull. The scapula is perforated. The pelvis is unfused and simple.

 
Brasilitherium

Brasilitherium riograndensis (Bonaparte et al., 2003; Early Norian, Late Triassic, 208 mya) was considered a stem mammal, but here nests at the base of the monotreme mammals despite the not-quite mammalian jaw joint. This may explain why monotreme ear bones are below and medial to the jawline, but in other mammals they are posterior to the jaw joint. The long rostrum includes as many as seven premolars and 4 molars.

Kuehneotherium
 

Bonaparte JF, Martinelli AG, Schultz CL and Rubert R 2003. The sister group of mammals: small cynodonts from the Late Triassic of Southern Brazil. Revista Brasileira de Paleontologia 5:5-27.

Kermack Dm, Kermack KA, Mussett F 1968. The Welsh pantothere Kuehneotherium praecursoris. Journal of the Linnean Society of London, Zoology. 47 (312): 407–423.

Li G and Luo Z-X. 2006. A Cretaceous symmetrodont therian with some monotreme-like postcranial features. Nature, 439:195–200.

Luo Z-X, Ji Q, Wible JR and Yuan C-X 2003. An Early Cretaceous tribosphenic mammal and metatherian evolution. Science 302:1934–1939.

Patterson B and Olson EC 1961. A triconodont mammal from the Triassic of Yunnan. In Vandebroek G (ed.), International Colloquium on the Evolution of Lower and Non Specialized Mammals. Koninklijke Vlaamse Academir voor Wetenschappen, Letteren en Schone Kunsten can Belgie 129-191.

Shaw G 1799. The Naturalist's Miscellany.

wiki/Akidolestes
wiki/Kuehneotherium

 
Pre-Mammals
Pachygenelus
Yanoconodon
Sinoconodon
 
Mammalia - Prototheria
Megazostrodon
Juramaia
Chaoyangodens
Tachyglossus
Ornithorhynchus
 
Mammalia - Metatheria
Eomaia and kin
Placentals - Eutheria
Monodelphis and kin
Carnivora
Nandinia and kin
Volitantia
Pteropus and kin
Glires
Rattus and kin
Primates
Notharctus and kin
Tenrecs - Whales
Andrewsarchus and kin
Basal Condylarthra
Onychodectes and kin
Edentata
Bradypus and kin
Basal Ungulata
Phenacodus and kin
Mesonychidae
Hippopotamus and kin
Artiodactyla
Giraffa and kin
Paenungulata
Elephas and kin
Perissodactyla
Equus and kin
 

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