South African and Argentinian palaeontologists have discovered a new early dinosaur from South Africa. The specimen was found in the late 1930s in the Zastron area of South Africa, about 30km from the Lesotho border. For a long time the remains of the dinosaur just languished on the shelves in the collections at the Evolutionary Science Institute (ESI) (then the Bernard Price Institute) in Johannesburg. A few years ago it was studied and considered to represent the remains of another South Africa dinosaur, Aardonyx.
However, close scrutiny of the fossilised bones of this approximately 200-million-year-old dinosaur have revealed that it is a completely new dinosaur. One of the most distinctive features is that one of its foot bones, the astragalus, has a “cross” shape, for which the dinosaur is named.
Considering the location of the fossil discovery, it was decided that a Sesotho name would be appropriate, and that since in Sesotho, “sefapano” means “cross”, the dinosaur should be named Sefapanosaurus.
Professor Anusuya Chinsamy-Turan, palaeobiologist and head of the department of biological sciences at the University of Cape Town (UCT), as well as Emil Krupandan, a PhD student from the same department at UCT, are part of the team that named the dinosaur.
The remains of the Sefapanosaurus include limb bones, foot bones and several vertebrae. Sefapanosaurus is represented by the remains of at least four individuals in the ESI collections. It is considered to be a medium-sized sauropodomorph dinosaur, so it is among the early members of the group that gave rise to the later long-necked giants of the Mesozoic.
Professor Chinsamy-Turan, co-principal investigator on the South Africa-Argentina research collaboration project and author of “Famous dinosaurs of Africa and Fossils for Africa”, says: “The discovery of Sefapanosaurus shows that there were several of these transitional early sauropodomorph dinosaurs roaming around Southern Africa about 200-million years ago.”
Most of the researchers involved in the write-up are supported by a National Research Foundation collaboration grant between South Africa and Argentina. Dr Alejandro Otero, an Argentinian palaeontologist, and Krupandan were visiting the ESI collections to look at early sauropodomorph dinosaurs when they noticed that the bones were distinctive from the other dinosaurs they were studying.
Krupandan, working on a dinosaur from Lesotho as part of his PhD studies, says: “As soon as I looked at the material I realised it was different to Aardonyx. This find indicates the importance of relooking at old material that has only been cursorily studied in the past, in order to re-evaluate past preconceptions about sauropodomorph diversity in light of new data.”
Dr Diego Pol, Argentinian co-principal investigator of the RSA-Argentina collaboration, says: “This and other recent dinosaur discoveries in Argentina and South Africa are revealing that the diversity of herbivorous dinosaurs in our continents was remarkably high back in the Jurassic, about 190-million years ago when South America, South Africa and other southern hemisphere continents were a single supercontinent known as Gondwana.”
Dr Jonah Choiniere, senior researcher in Dinosaur Palaeobiology at the University of the Witwatersrand ESI, says: “This new animal shines a spotlight on southern Africa and shows us just how much more we have to learn about the ecosystems of the past, even here in our own ‘backyard’.”
Dr Otero, lead author of the publication on Sefapanosaurus, says: “Sefapanosaurus helps to fill the gap between the earliest sauropodomorphs and the gigantic sauropods. Sefapanosaurus constitutes a member of the growing list of transitional sauropodomorph dinosaurs from Argentina and South Africa that are increasingly telling us about how they diversified.”
The scientific publication naming the dinosaur was published in the Zoological Journal of the Linnaean Society on 23 June 2015.