Researchers have identified a new 240-million-year-old prehistoric animal species from Tanzania named Dinodontosaurus isiyavamanda. Described in a study published September 16 in the Journal of Vertebrate Palaeontology, the herbivorous synapsid specimen sat in museum archives for over six decades, and its discovery now reshapes the timeline of early dinosaur evolution.
An international research team led by the University of Bristol described the animal, which lived during the Triassic period and belongs to the dicynodonts—a group of tusked, beaked herbivorous synapsids that flourished before dinosaurs rose to dominance. The new species, Dinodontosaurus isiyavamanda, was identified from fossil specimens recovered from the Lifua Member of Tanzania’s Manda Beds.
Sixty Years in Museum Archives
The journey of Dinodontosaurus isiyavamanda from a dusty basement drawer to international scientific headlines began more than 60 years ago. During a British expedition to what is now Tanzania in 1963, an extensive collection of synapsid fossils was unearthed and subsequently shipped to the Natural History Museum in London. While researchers studied parts of the haul, several specimens remained undescribed and sat in curation for decades.
The specimen at the center of the recent work was first examined by paleontologist Nigel Larkin during his master’s research at University College London back in 1994, when he suspected then that it represented a species new to science. Nearly three decades later, modern imaging technologies allowed researchers to return to the historical material.
“This fossil specimen from Tanzania has been in our care for over 60 years, and it’s wonderful that its identity has now been brought to light.”
Dr. Mike Day, curator of non-mammalian tetrapods at the Natural History Museum, London
Using advanced micro-CT scanning and 3D surface imaging alongside a more recently discovered fragmentary skull recovered in 2012, the research team analyzed an associated dicynodont skeleton. The anatomical data revealed that the bones belonged to the genus Dinodontosaurus. Previously, paleontologists believed Dinodontosaurus existed exclusively in South America, making the Tanzanian fossils the first confirmed record of the genus outside that continent.
Rewriting the Age of Tanzanian Fossil Beds
Beyond expanding the geographic range of an ancient animal, the discovery carries profound implications for dating the rocks in which it was buried. The Lifua Member deposits in Tanzania have historically yielded fossils proposed as some of the earliest possible dinosaurs, including Nyasasaurus parringtoni. For decades, geologists correlated these rock layers with formations in southern Africa, assuming an Anisian age roughly 247 to 242 million years ago.
Because Dinodontosaurus is securely documented in well-dated rock sequences in Brazil and Argentina, its presence in Tanzania provides a direct stratigraphic anchor. Recent radiometric dating from South American deposits indicates those overlapping rock layers are significantly younger than older South African sequences.
“The presence of the otherwise South American Dinodontosaurus in Tanzania indicates that the mid-upper Lifua Member was likely deposited at around the same time as the Dinodontosaurus Assemblage Zone of Brazil and the Chañares Formation of Argentina.”
Hady George et al., Journal of Vertebrate Palaeontology
This chronological shift places the mid-to-upper Lifua Member into the late Ladinian (242 to 237 million years ago) or Carnian (237 to 227 million years ago) stages. Consequently, the dinosaur candidates entombed within these strata appeared later in Earth’s history than prior estimates assumed.
Refining the Timeline of Dinosaur Origins
The realization that Tanzania’s fossil-bearing rock strata are up to 10 million years younger than previously thought alters how researchers interpret the cradle of early Mesozoic ecosystems. Hady George, a doctoral student at the University of Bristol and lead author of the study, emphasized the broader geological significance of the finding.
“Our discovery marks the first confirmed record of the genus Dinodontosaurus outside South America. The finding links the Tanzanian and South American fossil-bearing rocks, showing they are of equivalent age.”
Hady George, PhD student in the School of Earth Sciences at the University of Bristol
The study cautions that future evolutionary models investigating major Mesozoic clades—including the emergence of Dinosauria—must adjust for this younger chronological framework. The fossils effectively break down the assumption that East Africa preserves the oldest potential dinosaur fossils, shifting the baseline forward.
What Remains Unexplored in Museum Collections
The scientific team named the new species after the local region, noting that Dinodontosaurus isiyavamanda honors the land of the Wamanda people who inhabit the Tanzanian fossil area. Yet, the work on this particular collection is far from complete.
The Natural History Museum in London houses additional unstudied Dinodontosaurus material collected during the mid-twentieth century expeditions. Researchers intend to focus upcoming projects on the postcranial skeletons of these specimens, performing detailed biomechanical and ecological analyses.
By pairing legacy museum collections with modern imaging technology, paleontologists continue to extract unexpected insights from archives built generations ago, proving that historical holdings can alter our view of prehistoric life as effectively as fresh field digs.