Researchers have named a brand new species of iguanodontian dinosaur from fossils discovered on the Isle of Wight. The dinosaur has been named Comptonatus chasei. The fossil materials represents probably the most full iguanodontian skeleton found within the Wealden Group for over 100 years. This new taxon has been erected primarily based on quite a few distinctive traits (autapomorphies) associated to the cranium, the straight dentary bone and a markedly expanded pubic hip bone described as being “the dimensions of a dinner plate”.
A view of the top of the newly described iguanodontian Comptonatus chasei. Image credit score: John Sibbick.
Comptonatus chasei
The fossil materials is round 125 million years outdated (Barremian faunal stage). The dinosaur fossils was discovered within the cliffs of Compton Bay on the Isle of Wight in 2013 by fossil collector Nick Chase, earlier than he tragically died of most cancers. Dr Jeremy Lockwood, helped with the excavation of the bones and tooth. He then spent years rigorously evaluating these fossils to different Wealden Group iguanodontians earlier than he was assured that these fossils represented a brand new species.
Dr Jeremy Lockwood strolling on the seaside in entrance of the cliffs that mark the excavation web site. Image credit score: College of Portsmouth.
Dr Lockwood has develop into synonymous with Isle of Wight ornithopods together with Professor David Martill (College of Portsmouth) and Professor Susannah Maidment (London Pure Historical past Museum). These three scientists described Brighstoneus simmondsi, one other Isle of Wight ornithopod in 2021. The invention of Comptonatus chasei demonstrates that these dinosaurs had been notably various in the course of the Barremian to early Aptian faunal phases.
Lateral views of the skulls of three taxa of Isle of Wight iguanodontian dinosaurs. Comptonatus chasei (A), Brighstoneus simmondsi (B) and Mantellisaurus atherfieldensis (C). Image credit score: College of Portsmouth.
Honouring the Late Nick Chase
A complete of 149 fossil bones had been collected. The genus identify interprets as “Compton thunderer”. This dinosaur was named after Compton Bay the place the fossils had been discovered and the “thunderer” factor of the genus identify pertains to the big dimension of this dinosaur. Bone histology signifies that the animal was round 5 or 6 years outdated when it died. It’s estimated to have weighed round 9 hundred kilograms.
The species identify honours Nick Chase, winner of the Palaeontological Affiliation’s Mary Anning Award in 2018, who made the preliminary discovery and thru his lifetime contributed enormously to the collections on the Dinosaur Isle Museum on the Isle of Wight, and the Pure Historical past Museum, London.
The late Nick Chase who discovered the fossil stays in 2013. The species identify honours him, a winner of the Palaeontological Affiliation’s Mary Anning Award in 2018, Nick Chase made the preliminary discovery. Throughout his lifetime he contributed enormously to the research of the dinosaur biota of the Wessex Formation. Image credit score: College of Portsmouth.
Dr Lockwood commented:
“Nick had an exceptional nostril for locating dinosaur bones – he actually was a modern-day Mary Anning. He collected fossils each day in all weathers and donated them to museums. I hoped we’d spend our dotage amassing collectively as we had been of comparable ages, however sadly that wasn’t to be the case. Regardless of his many great discoveries through the years, together with probably the most full Iguanodon cranium ever present in Britain, that is the primary dinosaur to be named after him.”
The Comptonatus chasei excavation in 2013. Nick Chase (within the foreground sketching), Steve Hutt (blue jumper), Jeremy Lockwood (sporting gloves), and Penny Newberry analyzing the uncovered fossil materials. Image credit score: College of Portsmouth.
Distinctive Autapomorphies
Throughout the assortment and preliminary preparation it was thought that these fossils represented a Mantellisaurus atherfieldensis. Nonetheless, an in depth research recognized a number of autapomorphies (distinctive traits) that led to the erection of a brand new taxon.
Dr Lockwood defined:
“I’ve been in a position to present this dinosaur is totally different due to sure distinctive options in its cranium, tooth and different elements of its physique. For instance its decrease jaw has a straight backside edge, whereas most iguanodontians have a jaw that curves downwards. It additionally has a really massive pubic hip bone, which is way greater than different related dinosaurs. It’s like a dinner plate!”
The big pubis bone of Comptonatus pubis. The enlarged blade-like function of the pubis is a novel attribute that helped to outline this new taxon. Image credit score: College of Portsmouth.
The scientists are unsure as to why the pubic hip bone is so massive. It might have been for muscle attachments indicating that this ornithopod had a special mode of locomotion. Maybe it might have helped help the big abdomen, or performed a task in respiration.
The Geological Setting of Comptonatus chasei
Comptonatus chasei and Brighstoneus simmondsi fossils are related to the Wessex Formation of the Wealden Group. Nonetheless, the deposits the place Brighstoneous fossils have been discovered may be two million years older than the strata related to C. chasei. Conversely, Mantellisaurus atherfieldensis is geologically youthful than Comptonatus. Mantellisaurus fossils appear confined to the overlying Vectis Formation (Wealden Group). Because of this Comptonatus and Brighstoneus lived in the course of the early Barremian faunal stage of the Cretaceous. Mantellisaurus lived a number of million years later (late Barremian).
The scientists state that the Wessex Formation might have supported a larger range than beforehand realised, or that evolutionary and or migratory pressures resulted in faunal turnover. Comptonatus supplies additional proof for a larger iguanodontian range and it’s now unclear as to which iguanodontian taxon or taxa dominated the Wessex sub-basin in the course of the Barremian. As well as, the researchers postulate {that a} reassessment of ornithopod fossil materials could also be required, as with our improved understanding of the variations between these taxa, extra new species may be recognized.
Isle of Wight Dinosaur Taxa
Regardless of solely 4 new dinosaur species being described on the Isle of Wight in the entire of the twentieth century, there have been eight new species named within the final 5 years. A outstanding variety of new dinosaur taxa have been described from fossils discovered on the Isle of Wight. Ornithischians akin to Vectidromeus insularis, Brighstoneus simmondsi and Vectipelta barretti have been named.
To learn extra about Vectidromeus insularis: Vectidromeus – A New Hypsilophodontid.
An article on Brighstoneus simmondsi: A New Iguanodontid from the Isle of Wight.
A scale drawing of the just lately described Isle of Wight iguanodontian Brighstoneus. CollectA added a mannequin of Brighstoneus simmondsi to their CollectA Age of Dinosaur Well-liked vary of figures. Image credit score: Every part Dinosaur.
Image credit score: Every part Dinosaur
A brand new, armoured dinosaur from the Isle of Wight described in 2023 (Vectipelta barretti): New Armoured Dinosaur Honours Pure Historical past Museum Professor.
As well as, a number of theropod dinosaurs have been described together with Vectiraptor greeni, Ceratosuchops inferodios and Riparovenator milnerae. Moreover, there’s proof of a big spinosaurid (the “white rock spinosaurid”). These discoveries counsel that the Wessex Formation supported a larger range of dinosaurs than beforehand realised. It might additionally point out a considerable faunal turnover in the course of the deposition of the Wessex Formation deposits.
Historic relative of Velociraptor from “Dinosaur Isle”: Early Cretaceous Dromaeosaurid from the Isle of Wight.
To examine Ceratosuchops inferodios and Riparovenator milnerae: Two New Spinosaurids from the Isle of Wight.
Information in regards to the monumental “white rock spinosaurid”: Tremendous-sized Carnivorous Dinosaur from the Isle of Wight.
Every part Dinosaur acknowledges the help of a media launch from the College of Portsmouth within the compilation of this text.
The scientific paper: “Comptonatus chasei, a brand new iguanodontian dinosaur from the Decrease Cretaceous Wessex Formation of the Isle of Wight, southern England” by Jeremy A. F. Lockwood, David M. Martill and Susannah C. R. Maidment revealed within the Journal of Systematic Palaeontology.
The Every part Dinosaur web site: Dinosaur Fashions.