At the outset of the Jurassic Period, about 200 million years ago, the largest carnivorous dinosaurs were relatively small, with a body length of 3–5 metres. Now, an international team of scientists from the University of Cape Town, University of Manchester, UK, and Universidade de São Paulo, Brazil, have discovered the first evidence for an extremely large carnivorous dinosaur in southern Africa 200 million years ago.
This new study, published in PLOS One, reveals the very large, three-toed, 57 cm long and 50 cm wide footprints of these huge animals, informally called "megatheropods". With an estimated body length of about 9 metres and hip height of 2.7 metres, 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. These large tracks are unique with only one other site, in the Holy Cross Mountains, Poland, bearing similar aged tracks but of a 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.”
Notes to editors
Theropod dinosaurs, such as Allosaurus and iconic Tyrannosaurus, were some of the main bipedal predators during the Mesozoic Era (the ‘Age of Dinosaurs’). During the Early Jurassic, the size of theropod dinosaurs was usually small (less than 3–5 m 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. It considerably expands the range of body size for theropods in the Early Jurassic at the onset of their radiation.