| Sinodelphys | |
|---|---|
 | |
| Fossil specimen,Hong Kong Science Museum | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Clade: | Eutheria |
| Genus: | †Sinodelphys Luoet al., 2003 |
| Type species | |
| †Sinodelphys szalayi Luoet al., 2003 | |
Sinodelphys is anextinctmammal from theEarly Cretaceous, estimated to be 125 million years old. It was discovered and described in 2003 in rocks of theYixian Formation inLiaoning Province,China, by a team of scientists includingZhe-Xi Luo and John Wible.[1] While initially suggested to be the oldest knownmetatherian, later studies interpreted it as aeutherian.
Only one fossil specimen is known, a slab and counterslab given catalog number CAGS00-IG03. It is in the collection of theChinese Academy of Geological Sciences.
Sinodelphys szalayi grew only 15 cm (5.9 in) long and possibly weighed about 30 g (1.05 oz). Its fossilized skeleton is surrounded by impressions of fur and soft tissue, thanks to the exceptionalsediment that preserves such details. Luo et al. (2003) inferred from the foot structure ofSinodelphys that it was ascansorial tree-dweller, like the contemporaryEomaia and modernopossums such asDidelphis.Sinodelphys probably hunted worms and insects.[2]
Sinodelphys szalayi, living in China around 125 million years ago, was initially interpreted as the earliest knownmetatherian.[2][3][4] This makes it almost contemporary to the eutherianAcristatherium, which has been found in the same area.[5] However, Biet al. (2018) reinterpretedSinodelphys as an early member ofEutheria.[6]
