''Apatosuchus'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

genus of non-

crocodylomorph Crocodylomorpha is a group of pseudosuchian archosaurs that includes the crocodilians and their extinct relatives. They were the only members of Pseudosuchia to survive the end-Triassic extinction. During Mesozoic and early Cenozoic times, cro ...

loricatan pseudosuchian known from the Late Triassic of Germany. It is known from a partial holotype skull from the middle Stubensandstein (a deposit that dates back to the

Norian The Norian is a division of the Triassic Period. It has the rank of an age (geochronology) or stage (chronostratigraphy). It lasted from ~227 to million years ago. It was preceded by the Carnian and succeeded by the Rhaetian. Stratigraphic defi ...

stage and is part of the Löwenstein Formation) in Baden-Württemberg. The type species is ''Halticosaurus orbitoangulatus.'' ''A. orbitoangulatus'' was first described by German paleontologist

Friedrich von Huene Friedrich von Huene, born Friedrich Richard von Hoinigen, (March 22, 1875 – April 4, 1969) was a German paleontologist who renamed more dinosaurs in the early 20th century than anyone else in Europe. He also made key contributions about v ...

in 1932,Huene, F. von. (1932). ''Die fossile Reptil-Ordnung Saurischia, ihre Entwicklung und Geschichte. Monogr. Geol. Pal.'' 4 (1) pts. 1 and 2, viii + 361 pp. who considered it a species of the theropod dinosaur '' Halticosaurus''. Some later studies proposed that it was an early

or " sphenosuchian" like '' Saltoposuchus'', another pseudosuchian from the middle Stubensandstein of Baden-Württemberg. The name ''Apatosuchus'', "deceptive crocodile", was erected for ''H. orbitoangulatus'' by Hans-Dieter Sues and Rainer R. Schoch in

2013 File:2013 Events Collage V2.png, From left, clockwise: Edward Snowden becomes internationally famous for leaking classified NSA wiretapping information; Typhoon Haiyan kills over 6,000 in the Philippines and Southeast Asia; The Dhaka garment fact ...

when it was realized that the known material represented a pseudosuchian archosaur rather than a dinosaur, as a result of further preparation of the specimen, coining the ''

combinatio nova ''Combinatio nova'', abbreviated ''comb. nov.'' (sometimes ''n. comb.''), is Latin for "new combination". It is used in taxonomic biology literature when a new name is introduced based on a pre-existing name. The term should not to be confused wi ...

'' ''Apatosuchus orbitoangulatus''. ''Apatosuchus'' is now thought to be a

basal Basal or basilar is a term meaning ''base'', ''bottom'', or ''minimum''. Science * Basal (anatomy), an anatomical term of location for features associated with the base of an organism or structure * Basal (medicine), a minimal level that is nec ...

member of the clade Loricata. ''Apatosuchus'' is much smaller in size than other basal loricatans such as ''

Teratosaurus ''Teratosaurus'' is a genus of rauisuchians known from the Triassic Stubensandstein (Löwenstein Formation - Norian stage) of Germany. It is estimated to be 6 meters (19.5 ft) long. Discovery In 1860, Sixt Friedrich Jakob von Kapff at th ...

'' and '' Batrachotomus''.

Phylogeny

A phylogenetic analysis performed by Sues & Schoch (2013) found ''Apatosuchus'' to be the sister taxon of the clade formed by ''Batrachotomus'' and more derived loricatans. This position was supported by two unambiguous

synapomorphies In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have ...

: the presence of a ridge on the dorsal surface of squamosal along the edge of supratemporal fossa, and concaved rear portion of the nasals at the midline. The data matrix of Sues & Schoch (2013), a list of characteristics that was used in the analysis, was based on that of Nesbitt (2011), one of the most extensive on archosaurs. Below is a cladogram from the analysis.

References

Late Triassic reptiles of Europe Norian life Triassic Germany Fossils of Germany Fossil taxa described in 2013 Prehistoric pseudosuchian genera {{paleo-archosaur-stub