{"id":572945,"date":"2026-01-21T15:29:30","date_gmt":"2026-01-21T18:29:30","guid":{"rendered":"https:\/\/revistapesquisa.fapesp.br\/?p=572945"},"modified":"2026-01-21T15:29:30","modified_gmt":"2026-01-21T18:29:30","slug":"fossil-halves-separated-90-years-ago-reveal-unknown-jurassic-reptile-species","status":"publish","type":"post","link":"https:\/\/revistapesquisa.fapesp.br\/en\/fossil-halves-separated-90-years-ago-reveal-unknown-jurassic-reptile-species\/","title":{"rendered":"Fossil halves separated 90 years ago reveal unknown Jurassic reptile species"},"content":{"rendered":"

\u201cI\u2019ve seen that pose before,\u201d said Brazilian paleontologist Victor Beccari, a scientific assistant for the Bavarian State Collection for Paleontology and Geology in Germany, to himself when he saw a fossil of a reptile in the drawers of research material of the Natural History Museum in London, UK. The researcher thought that the outstretched reptile with an angled neck, in the specimen that preserves several bones, reminded him of a fossil he had previously examined at the Senckenberg Natural History Museum in Frankfurt, Germany. In fact, they were two parts of the same fossil\u2014the mold and the complete skeleton, like two sides of a sandwich: one with the filling, the other with its imprint\u2014and they both belonged to a reptile from the Jurassic period. The species, Sphenodraco<\/em> scandentis<\/em> was described at the time by Beccari and colleagues in an article published in July in the Zoological Journal of the Linnean Society<\/em>.<\/p>\n

The new species has only just been described, based on the specimen collected in 1930. \u201cIt is likely that the parts of this fossil have been separated for almost a century and were sold independently to the museums where they are now housed. The connection between them was lost, and only the Frankfurt half was known until know,\u201d says Beccari.<\/p>\n

At the time when they were found, the fossil from Frankfurt was classified as Homoeosaurus<\/em>, an extinct genus of rhynchocephalian\u2014a group close to lizards, whose sole living species today is the tuatara, a reptile from New Zealand. \u201cFor this reason, I didn\u2019t pay much attention at the time and didn\u2019t identify it as a new species. I made a note and continued with the research,\u201d says Beccari, who during his PhD\u2014which is now complete, with only the defense pending\u2014examined fossils of these reptiles in museums in Germany, England, the Netherlands, France, Argentina, and the USA. During this process, he ended up noticing the coincidence. It finally clicked when he analyzed the animal\u2019s limbs to better understand its lifestyle and noticed that they were very long, indicative of a tree-dwelling existence, unlike the land-dwelling Homoeosaurus<\/em>.<\/p>\n

There are other conflicting characteristics. \u201cThe head is triangular, the teeth face backward, and the humerus has a distinctive kind of crest for muscle attachment,\u201d says the paleontologist. Homoeosaurus<\/em> has a round head. This led him to compare it with other species that are also different. Kallimodon<\/em>, a Jurassic rhynchocephalian that lived in what is now Germany, has vertical teeth. Additionally, one of the hip bones, the ilium, of S. scandentis<\/em>, is smaller than in both of the other species.<\/p>\n

To ensure a precise comparison, Beccari and colleagues used geometric morphometrics, a statistical method that quantifies the shape of organisms based on anatomical coordinates, such as reference points on bones. In this comparison, they marked points on key bones such as the humerus, femur, and skull in modern species of rhynchocephalian and lizards.<\/p>\n

\"\"

Victor Beccari<\/span>The two sides of the fossil: the mold (left<\/em>), and the countermold, with the majority of the bones, found in different museumsVictor Beccari<\/span><\/p><\/div>\n

These points are plotted on a chart, where the closer they are to one another, the more similar the organisms are. Paleontologist Annie Hsiou, from the University of S\u00e3o Paulo’s Ribeir\u00e3o Preto School of Philosophy, Sciences, and Languages and Literature (FFCLRP-USP), who did not take part in the study, highlights the importance of both the method and the results of the research. \u201cWe see in the comparisons that, in several characteristics, the new species described stands out from the others, indicating a big difference,\u201d says the specialist in lepidosaur reptiles, the group to which the recently described species belongs.<\/p>\n

For Beccari, the discovery is important for the evolutionary history of the group because there is this idea that rhynchocephalians had little morphological diversity, which never changed. \u201cIt\u2019s as if only lizards were ecologically diverse, which is not true,\u201d he states. \u201cBefore lizards appeared, the rhynchocephalians prevailed in various lifestyles, including marine, terrestrial, and arboreal,\u201d<\/p>\n

\u201cIt was a very varied group, that lived across all the continents,\u201d Hsiou corroborates. Rhynchocephalians went into decline and near total extinction toward the end of the Cretaceous, approximately 66 million years ago, with only the tuatara remaining today. Paleontologists are still studying why this group has come so close to disappearing, while lizards, which are closely related, have not. \u201cSomething we have really taken into consideration is that rhynchocephalians already occupied different habitats, while lizards were smaller, had begun to disperse, and had a different reproductive cycle from what we see in the modern tuatara,\u201d says Hsiou.<\/p>\n

S. scandentis<\/em> lived on an archipelago that, by its very nature, encompassed a mosaic of habitats with multiple islands separated by a marine environment and barrier reefs. The islands were dominated by relatively small trees and inhabited by a fauna composed of pterosaurs, birds, and small dinosaurs.<\/p>\n

The group was also successful in South America. \u201cIn Brazil, we described three species of rhynchocephalians from the Triassic period in Rio Grande do Sul alone: Lanceirosphenodon ferigoloi<\/em>, Clevosaurus brasiliensis<\/em>, and Clevosaurus hadroprodon<\/em>,\u201d says Hsiou, who participated in their description (see<\/em> Pesquisa FAPESP issue n\u00b0 283<\/em><\/a>).<\/p>\n

Until 180 million years ago, South America, Africa, Australia, India, and Antarctica were joined together as part of the Gondwana supercontinent. At that time, Antarctica had a temperate to subtropical climate and may have acted as a continental bridge that aided the group\u2019s dispersal to Oceania. After the separation of Gondwana, New Zealand became isolated and may have served as a refuge for species of the group that lived there, such as the surviving tuatara.<\/p>\n

The story above was published with the title “A fossil in two halves<\/strong>” in issue 355 of September\/2025.<\/p>\n

Scientific article<\/strong>
\nBECCARI, V. et al.<\/em> An arboreal rhynchocephalian from the Late Jurassic of Germany, and the importance of the appendicular skeleton for ecomorphology in lepidosaurs<\/a>. Zoological Journal of the Linnean Society<\/strong>. Vol. 204, no. 3. July 2, 2025.<\/p>\n","protected":false},"excerpt":{"rendered":"Brazilian researcher discovers two parts of the same specimen in museums in Germany and the United Kingdom","protected":false},"author":753,"featured_media":572958,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"categories":[159],"tags":[209,224,255,266],"coauthors":[4945],"class_list":["post-572945","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-science","tag-biology","tag-ecology","tag-paleontology","tag-zoology"],"acf":[],"_links":{"self":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/572945","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/users\/753"}],"replies":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/comments?post=572945"}],"version-history":[{"count":1,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/572945\/revisions"}],"predecessor-version":[{"id":572970,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/572945\/revisions\/572970"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/media\/572958"}],"wp:attachment":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/media?parent=572945"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/categories?post=572945"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/tags?post=572945"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/coauthors?post=572945"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}