Juramaia

Juramaia Temporal range: Late Jurassic, 160 Ma PreЄ Є O S D C P T J K Pg N ↓
Restoration
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Synapsida
Class:	Mammalia
Clade:	Eutheria
Genus:	†Juramaia Luo et al., 2011
Species
†J. sinensis Luo et al., 2011 (type)

Juramaia is an extinct genus of very basal eutherian mammal from the Late Jurassic (Oxfordian stage) deposits of western Liaoning, China; it is a small shrew-like mammal of body length approximately 70-100 mm. Juramaia is known from the holotype BMNH PM1343, an articulated and nearly complete skeleton including incomplete skull preserved with full dentition. It was collected in the Daxigou site, Jianchang, from the Tiaojishan Formation dated at about 160 million years ago. It was first named by Zhe-Xi Luo, Chong-Xi Yuan, Qing-Jin Meng and Qiang Ji in 2011 and the type species is Juramaia sinensis. The discovery of Juramaia provides new insight into the evolution of placental mammals by showing that their lineage diverged from that of the marsupials 35 million years earlier than previously thought. Furthermore, its discovery fills gaps in the fossil record and helps to calibrate modern, DNA-based methods of dating the evolution. Based on climbing adaptations found in the forelimb bones, it has been suggested that the basal stock of Eutheria was arboral.

	Metatheria  Sinodelphys szalayi  Cenozoic metatherian  Eutheria  Juramaia sinensis  Montanalestes keeblerorum  Murtoilestes abramovi  Eomaia scansoria  Prokennalestes trofimovi  Cenozoic placentalia

See also

• Eomaia

External links

• 'Jurassic Mother' Found in China: Discovery News
• Juramaia sinensis - 160-Million-Year-Old Fossil Pushes Back Mammal Evolution
• Paleobiology Database: Juramaia sinensis