Explore this animal in Size of Extinct Animals ↗
493 / Paleozoic
Mesosaurus
Mesosaurus tenuidens
Needle teeth and a flattened tail mark one of the earliest amniotes to return to water.
View original image · 1600 × 1067- Time range
- About 299–280 million years ago
- Final stage
- Early Permian
- Geographic range
- Inland brackish lakes · South America and Africa
01 / DEFINITION & ECOLOGY
What was Mesosaurus?
Mesosaurus (Mesosaurus tenuidens) was an extinct organism known from About 299–280 million years ago, with a range in Inland brackish lakes · South America and Africa.
Life and ecology
It swam enclosed basins and filtered small crustaceans and other aquatic prey.
02 / DISAPPEARANCE
Why did Mesosaurus disappear?
Changing basin hydrology and aquatic ecosystems are possible context; the fossil record does not establish why the genus disappeared.
03 / EVIDENCE
How do scientists know about Mesosaurus?
Matching fossils on both Atlantic margins support Gondwanan connection; skeletons preserve ribs, tail and feet.
04 / SOURCES & FURTHER READING
Check the source record
Use the scientific name to compare taxonomy, occurrence records and the fossil record. Database coverage and classifications may differ.
05 / REVISION HISTORY
How has this record changed?
- Rewrote an extinction cause that presented environmental or faunal turnover as established; it is now given as context the record does not prove.
- Verified authoritative entity sources and added three responsive reconstruction sizes.
- Initial bilingual species record published.
06 / CORRECTIONS & ADDITIONS