| Keichousaurus | |
|---|---|
 | |
| Physical description | |
| Lifespan | Unknown |
| Average Size | 20-50 cm |
| Average weight | Estimated 4-5 kg |
| Diet | Carnivorous; likely fish |
| Conservational Status | |
| Status | Extinct |
| IUCN status | Fossil |
| Scientific classification | |
| Kingdom | Animalia |
| Phylum | Chordata |
| Class | Reptilia |
| Order | Sauropterygia |
| Family | Pachypleurosauridae |
| Genus | Keichousaurus |
| Species | Keichousaurus hui
Keichousaurus lusiensis Keichousaurus yuananensis |
Keichousaurus is a genus of very small nothosauroid marine reptiles. Fossil remains have been found in Mongolia and China, and date to the Norian stage of the Late Triassic period. Keichousaurus is the smallest known fossil marine reptile found to date.
The genus Keichousaurus consists of three species: K. hui, K. lusiensis, and K. yuananensis. Size variations and slight morphological differences separate the three species; however, some authors have proposed that such variations represent different stages of growth, rather than separate species.
While it is the smallest marine reptile known, Keichousaurus is highly variable in terms of size. The smallest specimens, which likely represent juveniles, are around 20 centimetres in length; the larger specimens being well over twice the size of the smallest.
Habitat
Fossil Keichousaurus are often preserved in exquisite detail, with delicate features such as fingers preserved. Based on these, it appears that Keichousaurus' possessed webbed feet rather than flippers; suggesting that it may have been among the less aquatic nothosaur species. Some have suggested that Keichousaurus inhabited sheltered lagoons and may have climbed out of the water in similar fashion to modern sea lions, while others have proposed that it inhabited mangrove swamps and freshwater lakes.
Reproduction
Small (possible juvenile) specimen.