Rimasuchus

Rimasuchus is an extinct genus of crocodile from the Miocene of Egypt and possibly Libya. Only one species - Rimasuchus lloydi - is currently known. It was previously thought to be a species of Crocodylus, but is now thought to be more closely related to the modern African dwarf crocodiles (Osteolaemus). The first fossil of Rimasuchus an incomplete skull with associated mandible, was collected by lieutenant colonel Arthur H. Lloyd in the early 20th century in Wadi Moghara, Egypt. The holotype specimen, CGM 15597, was given to the Egyptian Geological Museum and described by Fourtau in 1920 under the name Crocodylus lloydi. Other material includes an uncatalogued skull housed at the Natural History Museum, London (likewise from Wadi Moghara) and fossils found at Gebel Zelten in Libya. Eventually other skulls further south in Africa ended up being assigned to "Crocodylus" lloydi , with the oldest and southern-most material stemming from Namibia and the youngest fossils from Tanzania and Kenya in East Africa. This would have given the taxon a massive range both geographically and stratigraphically, spanning large parts of the continent from the Miocene up to the Pleistocene. However revisions of these fossils soon reduced the range of "Crocodylus" lloydi back to its original state. In 2003 the Namibian material was named Crocodylus gariepensis by Martin Pickford, who suggested that it was the true ancestor of the Nile crocodile. Pickford found his argument strengthened when shortly prior to the release of the publication "C." lloydi was found to be a distinct genus, named Rimasuchus. In 2010 Christopher Brochu and colleagues named Crocodylus anthropophagus based on remains from Tanzania and two years later Crocodylus thorbjarnarsoni was named from Kenya. With the Kenyan specimens assigned to their own species, previous size estimates indicating that Rimasuchus grew to massive sizes and even preyed on humans were rendered out of date. Furthermore, with their description Rimasuchus was effectively removed from the fossil record of East Africa and the Pleistocene.