An international team of scientists has discovered evidence of an extremely large carnivorous dinosaur that roamed southern Africa 200-million years ago.
At the outset of the Jurassic Period, about 200-million years ago, the largest carnivorous dinosaurs were relatively small, with a body length of 3m to 5m.
A new study by scientists from the University of Cape Town, University of Manchester, and Universidade de São Paulo, published in PLOS One, reveals the very large, three-toed, 57cm long and 50cm wide footprints of these huge animals, informally called “megatheropods”.
With an estimated body length of about 9m and hip height of 2,7m, this animal would have roamed a landscape otherwise dominated by much smaller carnivorous dinosaurs and a variety of herbivorous and omnivorous dinosaurs.
The megatheropod footprints were found on an informal road near the National University of Lesotho at Roma (Maseru District) in western Lesotho.
These are the largest theropod trackways ever found in Africa for this time period. Only one other site, in the Holy Cross Mountains, Poland, has tracks of a similar age, but marginally larger size.
UCT postdoctoral fellow Lara Sciscio, lead author on the publication and part of the discovery team, comments: “These new giant megatheropod tracks have been assigned a new species name (ambrokholohali).
“This name was, in part, derived in honour of Emeritus Professor David Ambrose for his detailed recording of the trace fossil heritage within the Roma Valley, Lesotho. In trying to relocate one of Prof Ambrose’s sites, we discovered the newly exposed megatheropod tracks reported in the article.”
Theropod dinosaurs, such as Allosaurus and iconic Tyrannosaurus, were some of the main bipedal predators during the Mesozoic Era — also known as the “Age of Dinosaurs”. During the Early Jurassic, the size of theropod dinosaurs was usually less than 3m to 5m in body length. It is only much later in time, about 120-million years or so within the Late Jurassic and Early to Middle Cretaceous, that truly large forms of theropods start making their appearance in the body and trace fossil record.
This makes the new discovery of these impressively large tracks more scientifically impactful, considerably expanding the range of body size for theropods in the Early Jurassic at the onset of their radiation.
Pictured: The estimated size of the Lesotho megatheropod based on the footprints discovered in Roma, Lesotho
Theropod image adapted, with permission, from Scott Hartman