Theriiformes

Theriiformes Temporal range: Middle Jurassic–Recent PreꞒ Ꞓ O S D C P T J K Pg N
Skull of the multituberculate Ptilodus (Allotheria)
Skeleton of Maotherium (Trechnotheria)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Clade:	Theriimorpha
Clade:	Theriiformes Rowe, 1988
Subgroups
†Allotheria †Tinodontidae Trechnotheria

Theriiformes is a clade of mammals. The term was coined by Timothy B. Rowe in his doctoral dissertation,^[1] and is defined as the clade formed by the most recent common ancestor of multituberculates (which form part of the broader group Allotheria, along with Gondwanatheria and likely all/part of Haramiyida) and Theria (the group containing marsupials and placentals).^[2] Mammals more closely related to therians than to multituberculates are included in the clade Trechnotheria.^[3] As multituberculates are usually considered more closely related to therians than monotremes are, it is considered to be a subgroup of the mammalian crown group.^[4]

The cladogram below follows Luo et al. (2016):^[5]

Mammalia	Australosphenida Theriimorpha Fruitafossor Eutriconodonta Theriiformes Gondwanatheria Multituberculata Trechnotheria Spalacotherioidea Cladotheria Dryolestoidea Theria

References

1. Rowe, T. (1988). "Definition, diagnosis, and origin of Mammalia". Journal of Vertebrate Paleontology. 8 (3): 241–264. doi:10.1080/02724634.1988.10011708.
2. Zachos, Frank; Asher, Robert, eds. (2018-10-22). Mammalian Evolution, Diversity and Systematics. De Gruyter. ISBN 978-3-11-034155-3.
3. Macrini, T. E.; Rougier, G. W.; Rowe, T. (2007). "Description of a Cranial Endocast from the Fossil Mammal Vincelestes neuquenianus (Theriiformes) and its Relevance to the Evolution of Endocranial Characters in Therians". The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology. 290 (7): 875–892. doi:10.1002/ar.20551.
4. Macrini, Thomas E.; Rougier, Guillermo W.; Rowe, Timothy (July 2007). "Description of a Cranial Endocast from the Fossil MammalVincelestes neuquenianus (Theriiformes) and its Relevance to the Evolution of Endocranial Characters in Therians". The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology. 290 (7): 875–892. doi:10.1002/ar.20551.
5. Luo, Zhe-Xi; Schultz, Julia A.; Ekdale, Eric G. (2016). "Evolution of the Middle and Inner Ears of Mammaliaforms: The Approach to Mammals". In Clack, Jennifer A.; Fay, Richard R.; Popper, Arthur N. (eds.). Evolution of the Vertebrate Ear. Vol. 59. pp. 139–174. doi:10.1007/978-3-319-46661-3_6.