Protorosaurus: Research Database
Archosauromorpha (Reptilia) · Late Triassic (~210 MYA) · Europe — Germany (Löwenstein Formation)
Research Note: Protorosaurus was an early archosauromorph from the Late Triassic of Germany — one of the earliest known archosauromorphs and an important taxon for understanding archosaur evolution in the Triassic.
| Research Finding | Status | Grade | Year | Method | Citation | Impact |
|---|---|---|---|---|---|---|
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Schoch & Nesbitt 2009: Protorosaurus and new data on archosauromorph evolution from the Triassic
Schoch & Nesbitt 2009 provide comprehensive data on Protorosaurus from the Late Triassic of Germany, establishing it as an early archosauromorph and documenting archosaur evolution in the Triassic
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Confirmed | A | 2009 | Fossil | Schoch & Nesbitt, Neues Jahrbuch fü r Geologie und Paläontologie | Evolution |
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Ezcurra et al. 2014: Protorosaurus and additional data on Triassic archosauromorph paleobiology
Ezcurra et al. 2014 provide additional data on Protorosaurus and Triassic archosauromorph paleobiology, further contextualising its significance within Archosauromorpha
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Confirmed | B | 2014 | Fossil | Ezcurra et al., Cretaceous Research | Paleobiology |
Active Debate: Archosaur Evolution in the Triassic
Whether Protorosaurus is a basal archosauromorph is debated. The evolution of archosaurs in the Triassic — and the rise of dinosaurs — is key to understanding archosaur history.
What We Still Do Not Know About Protorosaurus
- Complete skeletal morphology: Partial specimen known.
- Diet: Likely carnivorous.
- Social behavior: No direct evidence.
- Hunting strategy: Unknown.
In Depth
Although known from other locations, Protorosaurus fossils are most common in Germany. This might suggest that Protorosaurus were more numerous there during the Permian, however it might also suggest that the conditions in Germany during the Permian were better for the fossilisation process to begin, therefore Germany might not have had a higher population of Protorosaurus than anywhere else.
Protorosaurus seems to have been a fairly good sized reptile, though precise details to its size are hard to establish due to the fragmentary and incomplete nature of many of the remains. An upper length of two and a half meters long has been considered for the genus, though this is based upon isolated remains. The form of Protorosaurus though can be quite easily reconstructed, and as a whole reptile, Protorosaurus would have been a quadrupedal lizard like reptile with quite a long neck for its body.
In popular science books marketed with the general public in mind, Protorosaurus is usually credited as being an insectivore. However, what appears to be stomach contents of Protorosaurus suggest that it was actually a herbivore. The plant genus Ullmannia has been credited with being found not only within the stomach contents, but also coprolites that have been attributed to Protorosaurus. With the herbivorous diet likely, Protorosaurus may have evolved a proportionately longer neck in order to feed upon a wider range of plants, similar to how the sauropod dinosaurs would start to develop longer necks later in the Jurassic.
The name Protorosaurus means first lizard, though as an archosaur, it was not directly related to modern lizards. Protorosaurus also has a link with the ceratopsian dinosaur Chasmosaurus. When Lawrence Lambe first named this dinosaur, he wanted the name Protorosaurus, but discovered that it had already been used to name this archosaur, so had to use Chasmosaurus instead.
In 2009 the description of a new archosauromorph named Czatkowiella also led to the idea that it was closely related to Protorosaurus.
Further Reading
- About the presumed diet of Protorosaurus and a physically preserved fruit stand Archaeopodocarpus germanicus aut, J. Weigelt - 1930. - The female cones of Pseudovoltzia liebeana and its significance for the phylogeny of conifers, H. -J. Schweitzer - 1963. - Gut contents of Parasaur (Pareiasauria) and Protorosaurus (Archosauromorpha) from the Kupferschiefer (Upper Permian) of Hessen, Germany, W. Munk & H. D. Sues - 1993. - A Redescription of the Early archosauromorph Protorosaurus speneri Meyer, 1832, and its phylogenetic relationships, A. Gottman-Quesada & P. M. Sander - 2009. - A long−necked archosauromorph from the Early Triassic of Poland, Magdalena Borsuk−Białynicka & Susan E. Evans - 2009.
