PHILADELPHIA –- A fossil found more than 150 years ago has now been identified as the remains of a new species of dinosaur, the herbivore Kukufeldia tigatensis. The study was led by University of Pennsylvania graduate student Andrew McDonald and paleontologists from the Natural History Museum, London.
The fossil that led to the new identification, a 21-inch right dentary, the tooth-bearing bone of a plant-eating dinosaur, was originally studied in 1848 by Gideon Mantell, a British amateur paleontologist. Found in a quarry near Cuckfield, West Sussex, in England, the specimen was thought for decades to be from a previously known species, Iguanodon anglicus, due to similar tooth formation. Save for a few brief mentions by subsequent authors, the bone sat quietly in the collection of the Natural History Museum for more than a century.
But, a fresh examination by McDonald revealed that the specimen exhibited a feature unique to this dentary that distinguishes it from all other iguanodonts: a row of holes, known as neurovascular foramina, running along the front end of the bone that pierce the surface of the bone near the place at which the left dentary would have contacted the right. No other basal iguanodont dentaries exhibit this feature.
The bone also has a combination of primitive and advanced features that make it unique. It is straight along its entire length, a primitive feature, while having a vertical and expanded coronoid process, an advanced feature. The coronoid process is the large prong on the back end of the bone and was a site of attachment for jaw-closing muscles.
Kukufeldia is a basal iguanodont, similar to Jeyawati, a herbivore dinosaur described for the first time earlier this year, also by McDonald. Kukufeldia was probably a large plant eater that walked on all fours and had a long, low head with a sharp beak at the front for nipping vegetation.
The new identification makes the sample bone the holotype, or original specimen, for the new genus and species Kukufeldia tilgatensis. The dinosaur lived in the Early Cretaceous Epoch, approximately 136-137 million years ago.
The full name of the species, Kukufeldia tilgatensis, comes from the English village where the fossil was found, Cuckfield, and the nearby Tilgate Forest, the region where many of Mantell's finds were discovered.
MacDonald first started investigating the specimen after coming across a lithograph of Mantell’s paper. When Mantell coined the name Iguanodon, or iguana tooth, in 1825 for strange teeth found in a quarry near Cuckfield, it was only the second non-avian dinosaur to be recognized. During the subsequent two decades, Mantell refined his ideas about Iguanodon as more teeth and sundry postcranial elements periodically came to light.
“It seemed to me unusual compared to other iguanodonts and worthy of close scrutiny, especially because no one had thoroughly described it since 1848,” McDonald said.
His interest piqued by the mysterious bone, McDonald made it a point to examine the fossil during a two-week visit to the Natural History Museum in late 2009.
The study was funded by the Jurassic Foundation, the Evolving Earth Foundation, the University of Pennsylvania Paleobiology Summer Stipend and the Utah Friends of Paleontology.
The study was conducted by McDonald, of the Department of Earth and Environmental Science at Penn, along with Paul M. Barrett and Sandra D. Chapman of the Department of Palaeontology at the Natural History Museum, London.
The description was first published in the journal Zootaxa.
The bone now resides in the Natural History Museum along with hundreds of other iguanodont specimens from England.