Back Eutheria Afrikaans Eutheria AN ثدييات حقيقية Arabic Euteriyalar Azerbaijani وتریا AZB Eutheria Breton Eutheria BS Euteris Catalan Eutheria CEB Ευθήρια Greek
| Eutheria Temporal range: Late Jurassic–Holocene,
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| Skeleton of Microtherulum, a basal eutherian from the Early Cretaceous of China | |
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| Northern treeshrew (Tupaia belangeri), a placental eutherian from Southeast Asia | |
Scientific classification 
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Subclass: | Theria |
| Clade: | Eutheria Gill, 1872 |
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see text. | |
Eutheria (from Greek εὐ-, eú- 'good, right' and θηρίον, thēríon 'beast'; lit. 'true beasts'), also called Pan-Placentalia, is the clade consisting of placental mammals and all therian mammals that are more closely related to placentals than to marsupials
Eutherians are distinguished from noneutherians by various phenotypic traits of the feet, ankles, jaws and teeth. All extant eutherians lack epipubic bones, which are present in all other living mammals (marsupials and monotremes). This allows for expansion of the abdomen during pregnancy.[1] However epipubic bones are present in some primitive eutherians.[2] Eutheria was named in 1872 by Theodore Gill; in 1880, Thomas Henry Huxley defined it to encompass a more broadly defined group than Placentalia.[3]
The oldest-known eutherian species is Juramaia sinensis, dated at 161 million years ago from the early Late Jurassic (Oxfordian) of China.[4] However, this early dating has been questioned, and Juramaia may originate from Early Cretaceous instead, which would make it contemporaneous to several other known eutherians.[5]
- ^ Reilly, Stephen M.; White, Thomas D. (2003-01-17). "Hypaxial Motor Patterns and the Function of Epipubic Bones in Primitive Mammals". Science. 299 (5605): 400–402. Bibcode:2003Sci...299..400R. doi:10.1126/science.1074905. ISSN 0036-8075. PMID 12532019.
- ^ Guilhon, Gabby; Braga, Caryne; Milne, Nick; Cerqueira, Rui (November 2021). "Musculoskeletal anatomy and nomenclature of the mammalian epipubic bones". Journal of Anatomy. 239 (5): 1096–1103. doi:10.1111/joa.13489. ISSN 0021-8782. PMC 8546510. PMID 34195985.
- ^ Archibald, J David. Eutheria (Placental Mammals) (PDF). San Diego, California: San Diego State University.
- ^ Luo, Z.; C. Yuan; Q. Meng; Q. Ji (2011). "A Jurassic eutherian mammal and divergence of marsupials and placentals". Nature. 476 (7361): 42–45. Bibcode:2011Natur.476..442L. doi:10.1038/nature10291. PMID 21866158.
- ^ King, Benedict; Beck, Robin M. D. (2020-06-10). "Tip dating supports novel resolutions of controversial relationships among early mammals". Proceedings of the Royal Society B: Biological Sciences. 287 (1928): 20200943. doi:10.1098/rspb.2020.0943. ISSN 0962-8452. PMC 7341916. PMID 32517606.
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