Gnatusuchus [SEP] parent taxon
species name comes from an Amazonian village called Pebas. A phylogenetic analysis published alongside its initial description placed "Gnatusuchus" as the most basal member of the clade Caimaninae. Two other caimanines with crushing dentitions, "Kuttanacaiman" and "Globidentosuchus", were also found to be basal caimanines, suggesting that a specialized crushing dentition was ancestral to the group. Later caimanines, including most modern species, have more generalized dentitions, although a few derived species such as "C. wannlangstoni" seem to have reacquired crushing teeth. Below is
Gnatusuchus
Gnatusuchus is an extinct genus of caiman represented by the type species Gnatusuchus pebasensis from the Middle Miocene Pebas Formation of Peru. "Gnatusuchus" lived about 13 million years ago (Ma) in a large wetland system called the Pebas mega-wetlands that covered over one million square kilometers of what is now the Amazon Basin (the modern basin had not yet developed at that time and instead of draining from west to east into the Atlantic Ocean, river systems drained northward through the wetlands and into the Caribbean Sea).