Oldest fossil vomit

The oldest fossil vomit (or regurgitalite) is a 290-million-year-old chunk found in Germany's Bromacker site in the Thuringian Forest by palaeontologists in 2021, and dating to the early Permian period. It is believed to have derived from either a large pre-dinosaur mammal-like reptile known as Dimetrodon teutonis or another large pre-dinosaur carnivorous reptile called Tambacarnifex unguifalcatus. The remains are discussed in a paper published in the journal Scientific Reports on 30 January 2026.

Dimetrodon (characterized by a sail-like fin running along its back) and Tambacarnifex were apex Permian predators, and the chunk of vomit contains the bones of at least three smaller vertebrates, including Eudibamus cursoris and Thuringothyris mahlendorffae (the third is a currently unidentified but larger diadectid reptile) that it had recently consumed as prey.

This is the oldest regurgitalite discovered in a terrestrial context at the time the vomit was produced. The oldest marine fossil vomit are samples obtained from the Reingraben Shales in Polzberg, in lower Austria's Northern Calcareous Alps. Dating back to the Upper Triassic Period (237-201 million years ago), these regurgitalites consist of numerous entire shells and fragments of the ammonoid mollusc Austrotrachyceras, as well as rare teuthid (squid) arm hooks, and buccal cartilage of Phragmoteuthis, a prehistoric type of squid-like cephalopod. Based upon their size, shape and occurrence alongside vertebrate skeletal remains, these fossil vomit samples were probably produced by a large predatory cartilaginous fish such as Acrodus.

Regurgitalites are examples of what are known as trace fossils or ichnofossils. That is, instead of being the fossils of actual animals or plants, they are fossils of something produced and then left behind by an animal or plant. Other examples of trace fossils include fossil faeces (coprolites), fossil burrows, fossil footprints and fossil plant root cavities. Some fossil species are known only from trace fossils (and are therefore referred to as ichnospecies), but they are still given formal scientific names. Perhaps the most famous example is Chirotherium, a prehistoric animal known only from fossil footprint tracks, the shape and size of which lending support to the possibility that it was a species of pseudosuchian, related to the ancestors of crocodiles.