Mourasuchus

Mourasuchus is an extinct genus of giant, aberrant caiman from the Miocene of South America. Its skull has been described as duck like, being broad, flat and very elongate, closely resembling what is seen in "Stomatosuchus", an unrelated crocodylian that may also have had a large gular sac similar to those of pelicans or baleen whales. "Mourasuchus", is a strange nettosuchid with an unusually long, broad snout.
The synonym Carandaisuchus was used to describe fossils from the Ituzaingó Formation in Argentina demonstrating a pronounced bony occipital crest.
Description.
"Mourasuchus" had rows of small, conical teeth numbering around 40 on each side of the upper and lower jaws. "Mourasuchus" presumably obtained its food by filter feeding; the jaws were too gracile for the animal to have captured larger prey. It also probed the bottoms of lakes and rivers for food. Fossils have been found in the Pebas Formation at the Fitzcarrald Arch of Peru, where it coexisted with many other crocodylians, including the giant gharial, "Gryposuchus", and the alligatorid "Purussaurus", both of which were around long. The great diversity of crocodylomorphs in this Miocene-age (Tortonian stage, 8 million years ago) wetland suggests that niche partitioning was efficient, which would have limited interspecific competition.
Species.
The type species of "Mourasuchus" is "M. amazonensis", named in 1964 based on fossils found in the Solimões Formation of Amazonian Brazil. Another species, "M. atopus", was named based on fossils from the Honda Group at the Lagerstätte of La Venta in Colombia, after having been initially assigned to its own genus, "Nettosuchus", a year later in 1965. The latter species has a longer and narrower skull than the type species. A third species, "N. nativus", was named in 1985 based on fossils of the Urumaco Formation of Venezuela, but it was considered a junior synonym of "M. arendsi", found in the Ituzaingó Formation of Argentina, by Scheyer & Delfino (2016). A fourth species, "M. pattersoni", was described by Cidade et al. (2017). Indeterminate "Mourasuchus" fossils were found in the Yecua Formation of Bolivia.