Paleontologists have found and described a brand new ctenochasmatid pterosaurian mandible from the Late Jurassic Portland Limestone Formation of southern England.
Life reconstruction of the ctenochasmatid pterosaur Gladocephaloideus jingangshanensis. Picture credit score: Zhao Chuang.
“Pterosaur stays are uncommon within the Higher Jurassic layers of the UK, consisting principally of remoted bones or fragments of bones,” mentioned College of Portsmouth paleontologists Roy Smith and David Martill.
“Many information of Late Jurassic pterosaurs in the UK are of little greater than historic curiosity, and embody named species now considered nomina dubia.”
“Nonetheless, some materials is diagnostic, and several other species have stood the check of time.”
“By far the vast majority of Higher Jurassic pterosaurs in the UK have come from the Kimmeridge Clay Formation of southern England, with only a few occurrences from the Oxfordian a part of the Oxford Clay Formation of southern and japanese England, and a single incidence from the Kimmeridge Clay Formation of Scotland.”
“Regardless of this dearth of fabric, there have been some occurrences of related materials and the close to full cranium of Cuspicephalus scarfi on the sort locality of the Kimmeridgian stage.”
The brand new pterosaurian specimen is a mandible with at the least two, probably three enamel.
The fossil dates again to the Tithonian age of the Late Jurassic epoch, roughly 147 million years in the past.
It represents the geologically youngest Jurassic pterosaur from the UK.
“The specimen is an remoted mandible missing many of the postsymphyseal elements of the rami,” the paleontologists mentioned.
“It’s recognized as pterosaurian on account of its very skinny compacta and elongate type of the mandible.”
The brand new specimen was discovered within the Portland Limestone Formation of Dorset, southern United Kingdom.
It represents the primary pterosaur cranium materials to be documented, described and figured from this formation.
“The specimen was probably first discovered when a quarryman break up the stone utilizing the usual ‘feather and wedge’ process,” the researchers mentioned.
“This resulted in injury to the center a part of the specimen, while splitting of the jaw alongside its size additionally broken the specimen. The counterpart seems to not have been recovered.”
An absence of diagnostic options prevents the fossil’s referral to a recognized or new species however it may be confidently assigned to the pterosaur clade Ctenochasmatoidea.
“Ctenochasmatoids are a various group of pterosaurs with most genera notable for elongate, slender enamel intently spaced in lengthy, typically dorsally curved jaws,” the scientists mentioned.
“Certainly, one type, the South American Pterodaustro, has among the many longest enamel by way of length-diameter ratio of any tetrapod.”
“The basal euctenochasmatian Pterodactylus antiquus and ctenochasmatoid Ardeadactylus longicollum, each of Tithonian age, have quick conical enamel with a wider alveolar spacing than these of their ctenochasmatid allies.”
“The elongate slender mandible and quite a few intently spaced alveoli counsel it’s a member of Ctenochasmatidae.”
“A faint median ridge on the occlusal floor between two grooves, converging right into a median groove anteriorly, and the dearth of a definite premaxilla counsel the specimen is a part of the symphysis of the mandible.”
“That is the primary documented document of a pterodactyloid from the Portland Group of England.”
The findings had been printed this month within the Proceedings of the Geologists’ Affiliation.
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Roy E. Smith & David M. Martill. A ctenochasmatid pterosaur from the Portland Limestone Formation (Late Jurassic, Tithonian) of southern England. Proceedings of the Geologists’ Affiliation, printed on-line March 11, 2025l doi: 10.1016/j.pgeola.2025.101100
