Artwork showing the relative scale of humans and Nyasasaurus ('Lake Nyasa lizard'). This animal, from Tanzania, lived around 234 million years ago during the middle of the Triassic period; and as such, it may be the oldest known dinosaur (as of March 2022), predating the previous record-holder by 12 million years. It measured 2-3 metres long and was carnivorous. Its study has been difficult, because it is only known from a few vertebrae and a humerus.