The earliest known crown-group lepidosaurs are known from the Middle Triassic, however their stem group is poorly sampled, with only a few representative fossils found. This is partly due to the small
The right petrosal of Borealestes, NMS G.1992.47.121.1, as preserved. Digital reconstruction based on synchrotron scan data. Part of more complete skeleton NMS G.1992.47.121.1.
Notosuchians from Cretaceous continental environments of Gondwana have developed an unexpected array of morphologies comparable to mammals and their extinct relatives. However, this exceptional divers