''Angistorhinus'' (meaning "narrow snout" or "hook snout") is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

phytosaur Phytosaurs (Φυτόσαυροι in Greek, meaning 'plant lizard') are an extinct group of large, mostly semiaquatic Late Triassic archosauriform or basal archosaurian reptiles. Phytosaurs belong to the order Phytosauria and are sometimes ref ...

known from the

Late Triassic The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch a ...

period of

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

and

Wyoming Wyoming ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States, Western United States. It borders Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho t ...

, United States. It was first named by Mehl in

1913 Events January * January – Joseph Stalin travels to Vienna to research his ''Marxism and the National Question''. This means that, during this month, Stalin, Hitler, Trotsky and Tito are all living in the city. * January 3 &ndash ...

and the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

is ''Angistorhinus grandis''. Other species from Texas and Wyoming, ''A. alticephalus'' (Stovall and Wharton, 1936), ''A. gracilis'' (Mehl, 1915) and ''A. maximus'' (Mehl, 1928), are cospecific with the type species. ''Angistorhinus'' is known from the holotype UC 631, partial

skull The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate. In the human, the skull comprises two prominent ...

and lower

jaw The jaws are a pair of opposable articulated structures at the entrance of the mouth, typically used for grasping and manipulating food. The term ''jaws'' is also broadly applied to the whole of the structures constituting the vault of the mouth ...

s recovered from the

Popo Agie Formation The Popo Agie Formation ( )Locally "po-PO-zha" according to Don Pitcher, 2006, ''Moon Handbooks Wyoming,'' p. 26/ref>More ambiguous transcription of "po-po-zsha" at is a Triassic geologic Formation (geology), formation that outcrop, crops out in ...

, Chugwater Group,

and from the associated paratype UM 531, a partial skull, TMM 31098-1, skull and lower jaws and ROM 7977, partial skull and lower jaws, recovered from the 'Pre-Tecovas Horizon' in the Dockum Group,

. A possible second species, ''A. talainti'' is known from the

Triassic The Triassic ( ; sometimes symbolized 🝈) is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.4 Mya. The Triassic is t ...

Morocco Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to Algeria–Morocc ...

. In 1995, Long and Murry created the new combination, ''Angistorhinus megalodon'' by synonymy for '' Brachysuchus''. Hungerbühler and Sues (2001) hypothesised that ''Angistorhinus'' is a junior synonym of '' Rutiodon''. However, in 2010 Michelle R. Stocker retained the validity of '' Brachysuchus'' and of ''A. grandis''.

Description

''Angistorhinus'' was another of the early phytosaur genera. It was similar to ''

Parasuchus ''Parasuchus'' is an extinct genus of basal phytosaur known from the Late Triassic (late Carnian to early Norian stage) of Andhra Pradesh and Madhya Pradesh, India. At its most restricted definition, ''Parasuchus'' contains a single species, '' ...

'' but differed in having the nostrils located further back, towards and above the eyes. This was a more specialized condition that characterized all late phytosaurs. ''Angisthorhinus'' was a huge animal by any standards; the skull length was about 120–124 cm; estimated overall length 7 to 8 meters long, more in ''A. megalodon'', a very large, short and heavy-muzzled form sometimes given its own genus ('' Brachysuchus''), and which far exceeded in size any living crocodile.

References

{{Taxonbar, from=Q2287966 Phytosauria Prehistoric reptile genera Late Triassic reptiles of North America Fossil taxa described in 1913 Taxa named by Maurice Mehl