''Phytosaurus'' (meaning "plant lizard") is a

dubious Doubt is a mental state in which the mind remains suspended between two or more contradictory propositions, unable to be certain of any of them. Doubt on an emotional level is indecision between belief and disbelief. It may involve uncertainty, ...

genus of

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 ...

parasuchid

phytosaur Phytosaurs (Φυτόσαυροι in greek) are an extinct group of large, mostly semiaquatic Late Triassic archosauriform reptiles. Phytosaurs belong to the order Phytosauria. Phytosauria and Phytosauridae are often considered to be equivalent ...

found in an outcrop of the

Keuper The Keuper is a lithostratigraphic unit (a sequence of rock strata) in the subsurface of large parts of west and central Europe. The Keuper consists of dolomite, shales or claystones and evaporites that were deposited during the Middle and Late ...

(likely the

Exter Formation The Exter Formation is the only formation of the Upper Keuper or Rhätsandstein, and is a Formation (geology), geologic formation in Germany. It preserves fossils dating back to the Rhaetian of the Triassic period (specifically around 205 Ma).

) in

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

. ''Phytosaurus'' was the first phytosaur to be described, being done so by

Georg Friedrich von Jaeger Georg Friedrich Jaeger and from 1850 Georg Friedrich von Jaeger, (25 December 1785 - 10 September 1866) was a German physician and paleontologist. Life Jaeger was born in Stuttgart, the son of physician Christian Friedrich von Jäger and Luise ...

in 1828.G. F. Jaeger. (1828). Über die Fossile Reptilien, Welche in Württemberg Aufgefunden Sind n the Fossil Reptiles That Are Found in Württemberg ''Verlag der Metzler'schen Buchhandlung, Stuttgart'' 1-48 The

type species In 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 species that contains the biological type specimen ...

is ''P. cylindricodon'' and a second species, ''P. cubicodon'', is also known.

Discovery and naming

In 1826, the holotypes of both species were discovered in Wurttemburg,

at the "Neckar" site at the base of the hill which Wildenau Castle stands upon. The holotype of ''P. cylindricodon'' consists of parts of the skull and jaws, with natural casts of the teeth which, however, did not preserve their conical form but were flattened which led to the misunderstanding they were specialised in eating plant material, and the holotype of ''P. cubicodon'' consists of fragments of the jaw. Both species were named and described by von Jaeger (1828) and were first commented on by

von Meyer Meyer is a German surname, often but not always used with the Nobiliary particle "von" (of). Notable people sharing this surname include: * Christian Erich Hermann von Meyer (1801–1869), German palaeontologist, see m:de:Hermann von Meyer * G ...

(1837).von Meyer, H. (1837) “On the Structure of Fossil Saurians.” Many later authors, beginning with

Owen Owen may refer to: Origin: The name Owen is of Irish and Welsh origin. Its meanings range from noble, youthful, and well-born. Gender: Owen is historically the masculine form of the name. Popular feminine variations include Eowyn and Owena. ...

(1841), have classified both species of ''Phytosaurus'' as '' nomen dubia'' due to the lack of known diagnostic material. Owen (1841) had ''Phytosaurus'' classified as a synonym of ''

Mastodonsaurus ''Mastodonsaurus'' (meaning "teat tooth lizard") is an extinct genus of temnospondyl amphibian from the Middle Triassic of Europe. It belongs to a Triassic group of temnospondyls called Capitosauria, characterized by their large body size and pre ...

'', an unrelated amphibian, and later ''

Labyrinthodon ''Mastodonsaurus'' (meaning "teat tooth lizard") is an extinct genus of temnospondyl amphibian from the Middle Triassic of Europe. It belongs to a Triassic group of temnospondyls called Capitosauria, characterized by their large body size and pre ...

'', a now obsolete taxon. A partial phytosaur specimen found at the "UCMP V6333" locality of the

Dockum Formation The Dockum is a Late Triassic (approximately late Carnian through Rhaetian, or 223–200 Ma) geologic group found primarily on the Llano Estacado of western Texas and eastern New Mexico with minor exposures in southwestern Kansas, eastern Color ...

Texas Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...

was initially referred to ''Phytosauru'' sp., but has since been reclassified as an indeterminate mystriosuchine phytosaur.

Description

''P. cylindricodon'' appeared to have cylindrical teeth, while ''P. cubicodon'' appeared to have teeth that were square in shape. The conical teeth of the ''P. cylindricodon'' holotype appear to show evidence of grinding. ''Phytosaurus'' likely grew up to long and the skull of ''P. cylindricodon'' likely reached up to when complete.

Classification

''Phytosaurus'' likely belonged to the

Parasuchidae Parasuchidae is a clade of phytosaurs more derived than ''Diandongosuchus'', a basal phytosaur. It encompasses nearly all phytosaurs, include early ''Parasuchus''-grade forms as well as a more restricted clade of more specialized phytosaurs. This ...

, a family of

phytosaurs Phytosaurs (Φυτόσαυροι in greek) are an extinct group of large, mostly semiaquatic Late Triassic archosauriform reptiles. Phytosaurs belong to the order Phytosauria. Phytosauria and Phytosauridae are often considered to be equivalent g ...

References

{{Taxonbar, from=Q2101575 Nomina dubia Phytosaurs Fossil taxa described in 1828 Prehistoric reptile genera