Named By: Ronald S. Tyloski, Timothy B. Rowe, Richard A. Ketcham and Matthew W. Colbert - 2002.
Classification: Chordata, Reptilia, Crocodylomorpha, Goniopholididae.
Species: C. valliceps (type).
Size: Skull around 38 centimetres long. Total length unknown due to lack of post cranial remains.
Known locations: USA - Arizona/Navajo Nation - Kayenta Formation.
Time period: Sinemurian/Pliensbachian of the Jurassic.
Fossil representation: Partial skull.
skull that is the holotype of Calsoyasuchus is
incomplete with quite a
few pieces missing. However CT scanning of the skull has revealed the
presence of an intricate network of air passages and a double walled
secondary palate; a feature of modern crocodiles. How Calsoyasuchus
fits into the development of modern crocodiles is still uncertain
however considering that this skull construction may have developed in
many kinds of prehistoric crocodiles, with modern forms being the
only surviving crocs to still feature this. The discovery of
Calsoyasuchus also revealed that goniopholidid
appeared in the early Jurassic; previous discoveries were all dated
to the mid Jurassic.
Aside from Calsoyasuchus a growing number of other extinct creatures are also known from the Kayenta Formation, though perhaps the most famous of these so far is the theropod dinosaur Dilophosaurus.
- Calsoyasuchus valliceps, a new crocodyliform from the Early Jurassic Kayenta Formation of Arizona. - Journal of Vertebrate Paleontology. 22 (3): 593–61 - Ronald S. Tykoski, Timothy B. Rowe, Richard A. Ketcham & Matthew W. Colbert - 2002.