Temporal range: Middle Triassic, 243 mya
|Approximation of animal based on partial skeleton shown in black (first specimen, six vertebrae and a humerus) and blue (second specimen, three cervical vertebrae).|
Nesbitt et al., 2013
Nyasasaurus ("Lake Nyasa lizard") is an extinct genus of Archosaur reptile from the Middle Triassic Manda Beds of Tanzania. It may be the earliest known dinosaur. The discovery was a handful of bones from two individuals, so its anatomy is only partly known. The bones were collected in the early 1930s, but have only recently been analysed.
Researchers said: "Nyasasaurus possesses a unique combination of dinosaur character states and an elevated growth rate similar to that of definitive early dinosaurs. It demonstrates that the initial dinosaur radiation occurred over a longer timescale than previously thought (possibly 15 million years earlier)".
The find was six vertebrae and a humerus from one specimen, and five vertebrae from another. The humerus has a muscle attachment which is characteristic of dinosaurs (a long 'deltopectoral crest'). Other features are consistent with its being a basal dinosaur.
Previously, the oldest record of dinosaurs was from Argentina and dated back to the Upper Triassic Carnian stage, about 231.4 million years ago (mya). Nyasasaurus comes from a deposit that dates back to the Middle Triassic Anisian stage, meaning that it predates other early dinosaurs by about 15 million years.
References[change | change source]
- Nesbitt S.J. et al 2013. The oldest dinosaur? A Middle Triassic dinosauriform from Tanzania. Biological Letters, 9, 1.