''Rileyasuchus'' is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
of
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 g ...
from the
Rhaetian
The Rhaetian is the latest age of the Triassic Period (in geochronology) or the uppermost stage of the Triassic System (in chronostratigraphy). It was preceded by the Norian and succeeded by the Hettangian (the lowermost stage or earliest a ...
(
Late Triassic
The Late Triassic is the third and final epoch of the Triassic Period in the geologic time scale, spanning the time between Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch and followed by the Early Jurassic Epoch ...
)
Magnesian Conglomerate
The Magnesian Conglomerate is a geological formation in Clifton, Bristol in England (originally Avon), Gloucestershire and southern Wales, present in Tytherington, Durdham Down and Cromhall Quarry. It dates back to the Rhaetian stage of the Lat ...
of
England
England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe ...
. It has a confusing history, being associated with the taxonomy of ''
Palaeosaurus
''Palaeosaurus'' (or ''Paleosaurus'') is a genus of indeterminate archosaur known from two teeth found in the Bromsgrove Sandstone Formation and also either the Magnesian Conglomerate or the Avon Fissure Fill of Clifton, Bristol, England (ori ...
'' and ''
Thecodontosaurus
''Thecodontosaurus'' ("socket-tooth lizard") is a genus of herbivorous basal sauropodomorph dinosaur that lived during the late Triassic period ( Rhaetian age).
Its remains are known mostly from Triassic "fissure fillings" in South England. ' ...
'', and being a replacement name for a preoccupied genus (''
Rileya'', which had already been used by Ashmead, and Howard both in 1888 for a
hymenopteran
Hymenoptera is a large order of insects, comprising the sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are parasitic.
Females typica ...
).
[Howard, L.O. (1888). The chalcid genus ''Rileya''. Canadian Entomology 20:191-195.][Ashmead, W.H. (1888). A revised generic table of the Euryrtominae, with descriptions of new species. Pt I. Entomol. Am. 4:41-43.]
History and taxonomy
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 ...
named the new genus for two
vertebra
The spinal column, a defining synapomorphy shared by nearly all vertebrates, Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristi ...
e and a
humerus
The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a r ...
from deposits in
Bristol
Bristol () is a City status in the United Kingdom, city, Ceremonial counties of England, ceremonial county and unitary authority in England. Situated on the River Avon, Bristol, River Avon, it is bordered by the ceremonial counties of Glouces ...
.
[von Huene, F. (1902). Überischt über die Reptilien der Trias. ''Geologische und Paläontologie Abhandlungen, Neu Folge'' 8:97-156. ]erman Erman Rašiti may refer to:
Given name
* Erman Bulucu (born 1989), Turkish footballer
* Erman Eltemur (born 1993), Turkish karateka
* Erman Güraçar (born 1974), Turkish footballer
* Erman Kılıç (born 1983), Turkish footballer
* Erman Kunter (b ...
/ref> He had recognized it as a phytosaur by 1908 (by which point a few ''Palaeosaurus'' species had been added to the genus).[von Huene, F. (1908). On phytosaurian remains from the Magnesian Conglomerate of Bristol (''Rileya platyodon''). ''Annals and Magazine of Natural History'', series 8 1:228-230.]
It seems to have sat unrecognized for most of the 20th century, except for 1961 when Oskar Kuhn
Oskar Kuhn (7 March 1908, Munich – 1990) was a German palaeontologist.
Life and career
Kuhn was educated in Dinkelsbühl and Bamberg and then studied natural science, specialising in geology and paleontology, at the University of Munich, f ...
renamed it from ''Rileya'' to ''Rileyasuchus''.[Kuhn, O. (1961). ''Die Familien der rezenten und fossilen Amphibien und Reptilien.'' Meisenbach:Bamberg, 79 p.] Adrian Hunt in 1994 (doctoral dissertation) first suggested that it was a herrerasaurid, although this was never published.[Hunt, A.P. (1994). Unpublished doctoral dissertation]
discussed here
/ref> Benton ''et al.'' (2000) indicated that the type specimen
In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralizes th ...
was actually a chimera composed of a phytosaur humerus and ''Thecodontosaurus
''Thecodontosaurus'' ("socket-tooth lizard") is a genus of herbivorous basal sauropodomorph dinosaur that lived during the late Triassic period ( Rhaetian age).
Its remains are known mostly from Triassic "fissure fillings" in South England. ' ...
'' vertebrae.[Benton, M.J, Juul, L., Storrs, G.W., and Galton, P.M. (2000). Anatomy and systematics of the prosauropod dinosaur ''Thecodontosaurus antiquus'' from the upper Triassic of southwest England. ''Journal of Vertebrate Paleontology'' 20(1):77-108.] It is best regarded as a ''nomen dubium
In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application.
Zoology
In case of a ''nomen dubium'' it may be impossible to determine whether a s ...
''.
Paleobiology
As a phytosaur, it would have been a semi- aquatic crocodile
Crocodiles (family Crocodylidae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term crocodile is sometimes used even more loosely to include all extant me ...
-like predator
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill t ...
.
References
External links
''Rileyasuchus'' as herrerasaurid
{{Taxonbar, from=Q15378969
Phytosaurs
Late Triassic reptiles of Europe
Taxa named by Oskar Kuhn
Prehistoric reptile genera