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83-500: Poposaurus is an extinct genus of pseudosuchian archosaur from the Late Triassic of the southwestern and eastern United States. It belongs to the clade Poposauroidea , an unusual group of Triassic pseudosuchians that includes sail-backed, beaked, and aquatic forms. Fossils have been found in Wyoming , Utah , Arizona , Texas , and Virginia . Except for the skull, most parts of

166-400: A caudofemoralis longus (CFL) muscle that allowed them to flex theirs. Larger carnosaurs are found to have a lower CFL muscle-to-body-mass proportion that smaller carnosaurs. In addition to body similarities, most carnosaurs, especially most allosauroids are also united by certain skull features. Some of the defining ones include a smaller mandibular fenestra , a short quadrate bone, and

249-569: A "distal femur" in the holotype specimen of Poposaurus , but Galton interpreted this to be the fused end of the hip's pubis bones. Galton noted similarities between the hips of Poposaurus , Arizonasaurus , Bromsgroveia , Postosuchus , and Teratosaurus , and grouped them all in Poposauridae. Like paleontologists before him, Galton distinguished Poposaurus based on the unique shape of its ilium. In 1995, paleontologists Robert Long and Phillip Murry described new fossils of Poposaurus from

332-822: A basal grade of carnosaurs, paraphyletic with respect to Allosauroidea. Because the authors amended the definition of Allosauroidea to include all theropods that are closer to Allosaurus fragilis than to either Megalosaurus bucklandii or Neornithes, the Piatnitzkysauridae was found to fall within Allosauroidea. A cladogram displaying the relationships they recovered is shown below. Monolophosaurus Spinosauridae [REDACTED] Megalosauridae [REDACTED] Xuanhanosaurus Piatnitzkysauridae [REDACTED] Asfaltovenator Metriacanthosauridae [REDACTED] Allosauridae [REDACTED] The relationship between allosauroids and megalosauroids

415-417: A carnosaur. Carnosauria has traditionally been used as a dumping ground for all large theropods. Even non-dinosaurs, such as the rauisuchian Teratosaurus , were once considered carnosaurs. However, analysis in the 1980s and 1990s revealed that other than size, the group shared very few characteristics, making it polyphyletic . Most former carnosaurs (such as the megalosaurids , the spinosaurids , and

498-493: A distinctive form of respiration that involved abdominal muscles. The study hypothesized that Poposaurus had an ischiotruncus muscle running from the ischium at the back of the hip, across the pubis, and into the gastralia bones of the abdomen. In a form of respiration called cuirassal breathing , the ischiotruncus would contract and compress the trunk, pumping the lungs. [REDACTED] [REDACTED] [REDACTED] [REDACTED] Genus The composition of

581-508: A family of sauropodomorph dinosaurs. German paleontologist Friedrich von Huene considered it a very early stegosaur in 1950. In 1961, American paleontologist Edwin Harris Colbert gave an extensive description of the known material of Poposaurus and classified it as a theropod dinosaur. Colbert thought that Poposaurus could not have been a more primitive archosaur because it had hollow leg bones and complex vertebrae. He placed it in

664-407: A genus is determined by taxonomists . The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: Moreover, genera should be composed of phylogenetic units of

747-643: A later homonym of a validly published name is a nomen illegitimum or nom. illeg. ; for a full list refer to the International Code of Nomenclature for algae, fungi, and plants and the work cited above by Hawksworth, 2010. In place of the "valid taxon" in zoology, the nearest equivalent in botany is " correct name " or "current name" which can, again, differ or change with alternative taxonomic treatments or new information that results in previously accepted genera being combined or split. Prokaryote and virus codes of nomenclature also exist which serve as

830-922: A long narrow skull and modifications of the legs and pelvis such as the thigh ( femur ) being longer than the shin ( tibia ). Carnosaurs first appeared in the Middle Jurassic, around 176 mya. The last definite known carnosaurs, the carcharodontosaurs , became extinct in the Turonian epoch of the Cretaceous, roughly 90 mya; reportedly later remains of carcharodontosaurids, from the late Maastrichtian (70–66 mya) Bauru Group in Brazil , were later interpreted as those of abelisaurids . The phylogenetically problematic megaraptorans , which may or may not be carnosaurs, became extinct around 66 mya. Unquillosaurus , discovered in rocks dated to 75-70 mya, might potentially also be

913-621: A long time and redescribed as new by a range of subsequent workers, or if a range of genera previously considered separate taxa have subsequently been consolidated into one. For example, the World Register of Marine Species presently lists 8 genus-level synonyms for the sperm whale genus Physeter Linnaeus, 1758, and 13 for the bivalve genus Pecten O.F. Müller, 1776. Within the same kingdom, one generic name can apply to one genus only. However, many names have been assigned (usually unintentionally) to two or more different genera. For example,

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996-529: A new family called Poposauridae and a new suborder called Poposauroidea . To Nopsca, Poposauroidea was one of three suborders that made up the order Ornithopoda. Over the following years, many paleontologists supported this classification. For example, German paleontologist Oskar Kuhn classified Poposaurus in its own suborder of ornithischians, which he called Poposauria. In 1930, American paleontologist Oliver Perry Hay placed Poposaurus in Anchisauridae ,

1079-444: A newly named clade: Megaraptora. Megaraptora contained Megaraptor , Fukuiraptor , Orkoraptor , Aerosteon , and Australovenator . These genera were allied with the other neovenatorids on the basis of several features spread out throughout the skeleton, particularly the large amount of pneumatization present. The pneumatic ilium of Aerosteon was particularly notable, as Neovenator was the only other taxon known to have that trait at

1162-501: A number of primitive characteristics seen in basal tetanurans such as Allosaurus . Nevertheless, there are still a number of other traits that support megaraptorans as members of the Coelurosauria. Other taxa like Deltadromeus and Gualicho have been alternatively recovered as coelurosaurs or noasaurid ceratosaurs . Several recent analyses do not find a relationship between Neovenator and megaraptorans, which suggests that

1245-516: A phytosaur because the shape of its ilium was different and it had more sacral vertebrae fused to the hip. Mehl made comparisons between Poposaurus and the earlier named Dolichobrachium , also from the Triassic of Wyoming. Dolichobrachium was only known from some teeth, a humerus , and part of the pectoral girdle , so Mehl suggested that the Poposaurus and Dolichobrachium material could belong to

1328-510: A pseudosuchian, it is more closely related to living crocodilians than to dinosaurs. Poposaurus is thought to have evolved this form of locomotion independently, possibly from early archosaurs' ability to high walk . The first remains of Poposaurus were found in 1904 near Lander, Wyoming . In 1907, paleontologist J. H. Lees described this fossil, an ilium (part of the hip) from the Popo Agie Formation , and identified it as that of

1411-409: A reference for designating currently accepted genus names as opposed to others which may be either reduced to synonymy, or, in the case of prokaryotes, relegated to a status of "names without standing in prokaryotic nomenclature". An available (zoological) or validly published (botanical) name that has been historically applied to a genus but is not regarded as the accepted (current/valid) name for

1494-657: A scientific consensus has yet to emerge. One such clade is Neovenatoridae , a proposed clade of carcharodontosaurian carnosaurs uniting some primitive members of the group such as Neovenator with the Megaraptora , a group of theropods with controversial affinities. Other studies recover megaraptorans as basal coelurosaurs unrelated to carcharodontosaurs. Other theropods with uncertain affinities such as Gualicho , Chilantaisaurus and Deltadromeus are also sometimes included. Neovenatoridae, as formulated by these authors, contained Neovenator , Chilantaisaurus , and

1577-410: A short connection between the braincase and the palate. Allosauroid skulls are about 2.5 to 3 times longer as they are tall. Their narrow skull along with their serrated teeth allow carnosaurs to better slice flesh off of their prey. Carnosaur teeth are flat and have equally-sized denticles on both edges. The flat side of the tooth face the sides of the skull, while the edges align on the same plane as

1660-463: A similar center of mass across all sizes, which is found to be between 37% and 58% of the femoral length anterior to the hip. Other similarities across all carnosaurs include the structure of their hind limb and pelvis. The pelvis in particular is thought to be designed to reduce stress regardless of body size. In particular, the way the femur is inclined reduces the bending and torsion stress. Furthermore, like other animals with tails, carnosaurs possess

1743-427: A taxon; however, the names published in suppressed works are made unavailable via the relevant Opinion dealing with the work in question. In botany, similar concepts exist but with different labels. The botanical equivalent of zoology's "available name" is a validly published name . An invalidly published name is a nomen invalidum or nom. inval. ; a rejected name is a nomen rejiciendum or nom. rej. ;

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1826-455: A total of c. 520,000 published names (including synonyms) as at end 2019, increasing at some 2,500 published generic names per year. "Official" registers of taxon names at all ranks, including genera, exist for a few groups only such as viruses and prokaryotes, while for others there are compendia with no "official" standing such as Index Fungorum for fungi, Index Nominum Algarum and AlgaeBase for algae, Index Nominum Genericorum and

1909-410: Is absent in birds and probably non-avian dinosaurs as well. The extensor digitorum brevis was probably present on the foot of Poposaurus , but not in birds. The puboischiofemoralis externus muscle of Poposaurus is also similar to those of living crocodilians. Other aspects of the muscles of Poposaurus differ from those of crocodilians. For example, the puboischiofemoralis internus muscle originates on

1992-596: Is discouraged by both the International Code of Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants , there are some five thousand such names in use in more than one kingdom. For instance, A list of generic homonyms (with their authorities), including both available (validly published) and selected unavailable names, has been compiled by the Interim Register of Marine and Nonmarine Genera (IRMNG). The type genus forms

2075-432: Is laterally compressed, with a long and narrow hip structure. The pubis and ischium are elongated. The end of the pubis forms a distinct hook that is unique to Poposaurus and a few other early pseudosuchians. Poposaurus has five sacral vertebrae connecting the spine to the hip, three more than most early archosaurs. The hind legs are about twice as long as the arms and placed close together. Five digits are present on

2158-460: Is somewhat arbitrary. Although all species within a genus are supposed to be "similar", there are no objective criteria for grouping species into genera. There is much debate among zoologists about whether enormous, species-rich genera should be maintained, as it is extremely difficult to come up with identification keys or even character sets that distinguish all species. Hence, many taxonomists argue in favor of breaking down large genera. For instance,

2241-474: Is the type species , and the generic name is permanently associated with the type specimen of its type species. Should the specimen turn out to be assignable to another genus, the generic name linked to it becomes a junior synonym and the remaining taxa in the former genus need to be reassessed. In zoological usage, taxonomic names, including those of genera, are classified as "available" or "unavailable". Available names are those published in accordance with

2324-529: The Carnosauria , but because its ilium was distinct from all other archosaurs, Colbert placed Poposaurus in its own family, Poposauridae. In the same paper, Colbert described an ilium from the Dockum Group of Howard County, Texas , which he assigned to P. gracilis . In his 1977 study of Late Triassic saurischians, Peter Galton reclassified Poposaurus as a thecodont pseudosuchian. In 1915, Mehl described

2407-621: The International Code of Zoological Nomenclature ; the earliest such name for any taxon (for example, a genus) should then be selected as the " valid " (i.e., current or accepted) name for the taxon in question. Consequently, there will be more available names than valid names at any point in time; which names are currently in use depending on the judgement of taxonomists in either combining taxa described under multiple names, or splitting taxa which may bring available names previously treated as synonyms back into use. "Unavailable" names in zoology comprise names that either were not published according to

2490-799: The International Plant Names Index for plants in general, and ferns through angiosperms, respectively, and Nomenclator Zoologicus and the Index to Organism Names for zoological names. Totals for both "all names" and estimates for "accepted names" as held in the Interim Register of Marine and Nonmarine Genera (IRMNG) are broken down further in the publication by Rees et al., 2020 cited above. The accepted names estimates are as follows, broken down by kingdom: The cited ranges of uncertainty arise because IRMNG lists "uncertain" names (not researched therein) in addition to known "accepted" names;

2573-509: The Placerias quarry in the Chinle Formation of Arizona . Among the new material were parts of the lower limb, including the tibia and calcaneum . They removed Postosuchus from Poposauridae, claiming that the material used in this assignment was a chimera , or a collection of bones belonging to different animals. The pubis of Postosuchus was in fact a pubis of Poposaurus , leading to

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2656-527: The ceratosaurs ) were reclassified as more primitive theropods. Others (such as the tyrannosaurids ) that were more closely related to birds were placed in Coelurosauria . Modern cladistic analysis defines Carnosauria as those tetanurans sharing a more recent common ancestor with Allosaurus than with modern birds. Carnosaurs share certain distinctive features, one of which is a triangular-shaped pubic boot . They also have 3 fingers per hand, with

2739-419: The nomenclature codes , which allow each species a single unique name that, for animals (including protists ), plants (also including algae and fungi ) and prokaryotes ( bacteria and archaea ), is Latin and binomial in form; this contrasts with common or vernacular names , which are non-standardized, can be non-unique, and typically also vary by country and language of usage. Except for viruses ,

2822-469: The phytosaur Paleorhinus bransoni . In 1915, paleontologist M. G. Mehl named Poposaurus based on more complete material from the Popo Agie Formation, including vertebrae, hips, and limb bones. He cited the holotype as [Walker Museum] 602, but in fact the holotype is UR 357. Mehl concluded that the ilium described by Lees, UR 358, also belonged to Poposaurus . He did not classify Poposaurus as

2905-404: The platypus belongs to the genus Ornithorhynchus although George Shaw named it Platypus in 1799 (these two names are thus synonyms ) . However, the name Platypus had already been given to a group of ambrosia beetles by Johann Friedrich Wilhelm Herbst in 1793. A name that means two different things is a homonym . Since beetles and platypuses are both members of the kingdom Animalia,

2988-402: The 1970s however, Poposaurus has been considered a pseudosuchian archosaur more closely related to crocodilians than dinosaurs. Most of its close relatives (such as the large-bodied rauisuchids and ctenosauriscids ) were obligate quadrupeds that could not walk on two legs. Although the entire skeleton was unknown, Poposaurus was expected to be similar in appearance to its relatives. In 2011,

3071-465: The Allosauroidea as Allosaurus , Sinraptor , their most recent common ancestor , and all of its descendants. Thomas R. Holtz and colleagues and Phil Currie and Ken Carpenter , among others, have followed this node-based definition. Depending on the study, Carnosauria and Allosauroidea are sometimes considered synonymous. In such cases, several researchers have elected to use Allosauroidea over Carnosauria. The following family tree illustrates

3154-466: The above hypothesis. Novas and colleagues conducted an analysis in 2012 which found that Neovenator was closely related to carcharodontosaurids, simultaneously found Megaraptor and related genera to be coelurosaurs closely related to tyrannosaurids . However, Novas et al. subsequently found that megaraptorans lacked most of the key features in the hands of derived coelurosaurs including Guanlong and Deinonychus . Instead, their hands retain

3237-464: The acetabulum faces laterally and the head of the femur is angled to fit into it. Although they evolved bipedal locomotion independently, Poposaurus and dinosaurs inherited a propensity for erect hind-limb driven movement from an early archosaur ancestor. The posture of this ancestral archosaur can be inferred from a method called extant phylogenetic bracketing . Archosauria is a crown group represented today by birds and crocodilians , meaning that

3320-874: The aquatic Qianosuchus to be successively more basal poposauroids. Below is the cladogram from Gauthier et al. (2011): Avemetatarsalia Ornithosuchidae Gracilisuchus Turfanosuchus Revueltosaurus Aetosauria Ticinosuchus Qianosuchus Arizonasaurus Xilousuchus Poposaurus Lotosaurus Sillosuchus Shuvosaurus Effigia Prestosuchus Saurosuchus Batrachotomus Fasolasuchus Rauisuchus Polonosuchus Postosuchus Crocodylomorpha When M. G. Mehl first named Poposaurus in 1915, he described it as "a well-muscled creature light in weight, possibly bipedal in gait occasionally, and most assuredly swift in movement." Mehl based this description on its long limb bones and deep hip socket, two features which link it with bipedal dinosaurs. Since

3403-442: The base for higher taxonomic ranks, such as the family name Canidae ("Canids") based on Canis . However, this does not typically ascend more than one or two levels: the order to which dogs and wolves belong is Carnivora ("Carnivores"). The numbers of either accepted, or all published genus names is not known precisely; Rees et al., 2020 estimate that approximately 310,000 accepted names (valid taxa) may exist, out of

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3486-524: The early Carnian -aged Doswell Formation of Virginia, marking the first occurrence of this genus from eastern North America. This material was found at the same locality as Doswellia and was first mentioned in the 1980 paper describing it, where it was tentatively referred to as indeterminate rauisuchian remains. With the tail comprising about half the body length, Poposaurus was about 4–5 metres (13–16 ft) long and weighed 90 to 100 kilograms (200 to 220 lb) as an adult. The body of Poposaurus

3569-563: The end of the Mesozoic era, dating to the early Maastrichtian stage of the latest Cretaceous period, about 70 million years ago. The cladogram below follows a 2016 analysis by Sebastián Apesteguía, Nathan D. Smith, Rubén Juarez Valieri, and Peter J. Makovicky based on the dataset of Carrano et al. (2012). Metriacanthosauridae [REDACTED] Allosauridae [REDACTED] Carcharodontosauridae [REDACTED] Deltadromeus Gualicho Subsequent analyses have contradicted

3652-436: The first archosaur was the last common ancestor of all birds and crocodilians. All birds have a fixed erect stance, and crocodilians have the ability to high walk with their limbs erect. If an erect stance is considered homologous in birds and crocodilians (most likely), phylogenetic bracketing implies that they inherited this trait from their common ancestor and that this ancestor also had an erect stance. With this reasoning,

3735-501: The first archosaurs are thought to have had the ability to high walk. Poposaurus and dinosaurs achieved a bipedal posture as their legs increased in size, their hips strengthened, and their spines adapted for dorsoventral flexion. Other adaptations that may have facilitated bipedal locomotion include the development of a chambered heart and lungs with unidirectional airflow (both of which are assumed present in Poposaurus through phylogenetic bracketing). The leg musculature of Poposaurus

3818-428: The foot, but the fifth is reduced to a small splint of bone next to the metatarsals . The calcaneum bone extends far from the ankle to form a distinct heel. Poposaurus is a member of the family Poposauridae , part of the larger pseudosuchian group Poposauroidea . It is closely related to other Triassic pseudosuchians like ctenosauriscids and shuvosaurids . Like Poposaurus , shuvosaurids were bipedal. When

3901-402: The forelimbs, hind limbs, hips, ribs, dorsal vertebrae, and much of the tail. Another specimen of Poposaurus from Arizona, PEFO 34865, includes not only postcranial remains but also cranial remains, confirming that Poposaurus was a hyper-carnivorous predator. In 2022, the partial remains (fragmentary thoracic vertebrae and part a right humerus) of an immature P. gracilis were described from

3984-446: The form "author, year" in zoology, and "standard abbreviated author name" in botany. Thus in the examples above, the genus Canis would be cited in full as " Canis Linnaeus, 1758" (zoological usage), while Hibiscus , also first established by Linnaeus but in 1753, is simply " Hibiscus L." (botanical usage). Each genus should have a designated type , although in practice there is a backlog of older names without one. In zoology, this

4067-727: The generic name (or its abbreviated form) still forms the leading portion of the scientific name, for example, Canis lupus lupus for the Eurasian wolf subspecies, or as a botanical example, Hibiscus arnottianus ssp. immaculatus . Also, as visible in the above examples, the Latinised portions of the scientific names of genera and their included species (and infraspecies, where applicable) are, by convention, written in italics . The scientific names of virus species are descriptive, not binomial in form, and may or may not incorporate an indication of their containing genus; for example,

4150-465: The head to the hip is between 38% and 46% of the total body length. Carnosaurs scaled their limbs relative to their body in a way similar to how other large theropods, like the tyrannosaurids , did. During the Cretaceous, some carnosaurs grew to sizes similar to those of the largest tyrannosaurids. These large carnosaurs lived in the same time period as the other large theropods found in the upper Morrison and Tendaguru formations. Carnosaurs maintained

4233-536: The interrelationships between the four major groups (or families) of carnosaurs. It is a simplified version of the tree presented in the 2012 analysis by Carrano, Benson and Sampson after they excluded three "wildcard" taxa Poekilopleuron , Xuanhanosaurus , and Streptospondylus . Metriacanthosauridae [REDACTED] Allosauridae [REDACTED] The composition of the clade Carnosauria has been controversial among scientists since at least 2010 . Different clades have been recovered by different authors, and

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4316-628: The largest component, with 23,236 ± 5,379 accepted genus names, of which 20,845 ± 4,494 are angiosperms (superclass Angiospermae). By comparison, the 2018 annual edition of the Catalogue of Life (estimated >90% complete, for extant species in the main) contains currently 175,363 "accepted" genus names for 1,744,204 living and 59,284 extinct species, also including genus names only (no species) for some groups. The number of species in genera varies considerably among taxonomic groups. For instance, among (non-avian) reptiles , which have about 1180 genera,

4399-520: The latter were not carnosaurs or allosauroids. As a result of these findings, and the fact that Neovenator itself is the only uncontroversial neovenatorid, the family Neovenatoridae sees little use in recent publications. In 2019, Rauhut and Pol described Asfaltovenator vialidadi , a basal allosauroid displaying a mosaic of primitive and derived features seen within Tetanurae . Their phylogenetic analysis found traditional Megalosauroidea to represent

4482-477: The lizard genus Anolis has been suggested to be broken down into 8 or so different genera which would bring its ~400 species to smaller, more manageable subsets. Carnosauria This is an accepted version of this page Allosauroidea ? Marsh, 1878 Carnosauria is an extinct group of carnivorous theropod dinosaurs that lived during the Jurassic and Cretaceous periods. While Carnosauria

4565-551: The mistaken classification. Long and Murry separated poposaurids like Poposaurus , Bromsgroveia , and the newly named Lythrosuchus from rauisuchians like Postosuchus , which they held in the family Rauisuchidae . The known material of Poposaurus was again described in 2007, along with two new specimens from the Tecovas Formation of Texas and the Petrified Forest of Arizona. Long and Murry's Lythrosuchus langstoni

4648-403: The most (>300) have only 1 species, ~360 have between 2 and 4 species, 260 have 5–10 species, ~200 have 11–50 species, and only 27 genera have more than 50 species. However, some insect genera such as the bee genera Lasioglossum and Andrena have over 1000 species each. The largest flowering plant genus, Astragalus , contains over 3,000 species. Which species are assigned to a genus

4731-428: The name could not be used for both. Johann Friedrich Blumenbach published the replacement name Ornithorhynchus in 1800. However, a genus in one kingdom is allowed to bear a scientific name that is in use as a generic name (or the name of a taxon in another rank) in a kingdom that is governed by a different nomenclature code. Names with the same form but applying to different taxa are called "homonyms". Although this

4814-459: The nearly complete subadult specimen YPM VP 057100 was described. The specimen confirmed Mehl's description, revealing that Poposaurus was indeed bipedal. The skeleton preserves both the fore and hind limbs, showing that Poposaurus had much shorter arms than legs. Although Poposaurus and early dinosaurs were both bipedal, the method of locomotion evolved independently in each group. The independent origins are shown through several differences in

4897-623: The position of Carnosauria within Theropoda. It is a simplified version of the tree presented in a synthesis of the relationships of the major theropod groups based on various studies conducted in the 2010s.   Coelophysoidea   [REDACTED] Dilophosauridae [REDACTED] Ceratosauria [REDACTED] Megalosauroidea [REDACTED] Carnosauria / Allosauroidea [REDACTED] Tyrannosauroidea [REDACTED] Compsognathidae [REDACTED] Maniraptora [REDACTED] The cladogram presented below illustrates

4980-526: The provisions of the ICZN Code, e.g., incorrect original or subsequent spellings, names published only in a thesis, and generic names published after 1930 with no type species indicated. According to "Glossary" section of the zoological Code, suppressed names (per published "Opinions" of the International Commission of Zoological Nomenclature) remain available but cannot be used as the valid name for

5063-577: The same animal. Mehl noted similarities between Poposaurus and theropod dinosaurs, including its hollow leg bones and deep hip socket, but did not consider it a dinosaur because each sacral vertebra supported only one rib (theropods usually have multiple ribs projecting from each sacral vertebra). In the following years, Poposaurus was assigned to many different groups of reptiles. Hungarian paleontologist Franz Nopcsa classified it as an ornithischian dinosaur in 1921, identifying similarities with iguanodonts and camptosaurs . In 1928, Nopcsa placed it in

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5146-466: The same kind as other (analogous) genera. The term "genus" comes from Latin genus , a noun form cognate with gignere ('to bear; to give birth to'). The Swedish taxonomist Carl Linnaeus popularized its use in his 1753 Species Plantarum , but the French botanist Joseph Pitton de Tournefort (1656–1708) is considered "the founder of the modern concept of genera". The scientific name (or

5229-408: The scientific epithet) of a genus is also called the generic name ; in modern style guides and science, it is always capitalised. It plays a fundamental role in binomial nomenclature , the system of naming organisms , where it is combined with the scientific name of a species : see Botanical name and Specific name (zoology) . The rules for the scientific names of organisms are laid down in

5312-412: The second and third digit being approximately equal in length. The femur is larger than the tibia. Another defining feature of carnosaurs is that the chevron bases on their tails have anterior and posterior bone growth. The largest carnosaurs can reach up to 10 meters in length. The length of the body from the tail to the hip is between 54% and 62% of the total body length, and the length of the body from

5395-472: The skeleton are known. The type species , P. gracilis , was described and named by Maurice Goldsmith Mehl in 1915. A second species, P. langstoni , was originally the type species of the genus Lythrosuchus . Since it was first described, Poposaurus has been variously classified as a dinosaur , a phytosaur , and a " rauisuchian ". Like theropod dinosaurs, Poposaurus was an obligate biped, meaning that it walked on two legs rather than four. However, as

5478-408: The skeletons of Poposaurus and dinosaurs. Unlike dinosaurs, Poposaurus has the characteristic crurotarsal ankle of pseudosuchians, usually associated with quadrupedal locomotion. Poposaurus also has a "pillar erect" stance in which the acetabulum or hip socket faces downward and is positioned directly over the head of the femur. In contrast, dinosaurs have "buttress erect" hip structures in which

5561-539: The skull. From analyzing the skull of different carnosaurs, the volume of the cranial vault ranges between 95 milliliters in Sinraptor to 250 milliliters in Giganotosaurus . Allosaurus and Concavenator preserve skin impressions showing their integument . In Allosaurus, skin impressions showing small scales measuring 1-3 mm are known from the side of the torso and the mandible . Another skin impression from

5644-497: The specific name particular to the wolf. A botanical example would be Hibiscus arnottianus , a particular species of the genus Hibiscus native to Hawaii. The specific name is written in lower-case and may be followed by subspecies names in zoology or a variety of infraspecific names in botany . When the generic name is already known from context, it may be shortened to its initial letter, for example, C. lupus in place of Canis lupus . Where species are further subdivided,

5727-484: The specimen YPM VP 057100 was described by Gauthier et al. in 2011, Poposaurus was included in a phylogenetic analysis. Poposaurus was placed within Poposauroidea as the sister taxon to the large-bodied herbivorous Lotosaurus and the shuvosaurids. This means that Poposaurus is more closely related to Lotosaurus and shuvosaurids than it is to any other pseudosuchian. The analysis found ctenosauriscids and

5810-436: The spine in crocodilians and on the hip in Poposaurus . The hip origin for this muscle is considered to be the original condition for archosaurs, since it is also seen in birds and non-avian dinosaurs. Poposaurus is thought to have had adductor muscles that were even larger than dinosaurs, as their insertion site runs along the entire length of the femur . The 2011 study of the leg musculature of Poposaurus also suggested

5893-412: The standard format for a species name comprises the generic name, indicating the genus to which the species belongs, followed by the specific epithet, which (within that genus) is unique to the species. For example, the gray wolf 's scientific name is Canis lupus , with Canis ( Latin for 'dog') being the generic name shared by the wolf's close relatives and lupus (Latin for 'wolf') being

5976-496: The tail, as well as scutes on the feet along with small scales. A series of knobs on the ulna of Concavenator have been interpreted by some authors as quill knobs theorized to have supported primitive quills; however this interpretation has been questioned, and they have been suggested to represent traces of ligaments instead. Within Carnosauria, there is a slightly more exclusive clade, Allosauroidea . The clade Allosauroidea

6059-403: The taxon is termed a synonym ; some authors also include unavailable names in lists of synonyms as well as available names, such as misspellings, names previously published without fulfilling all of the requirements of the relevant nomenclatural code, and rejected or suppressed names. A particular genus name may have zero to many synonyms, the latter case generally if the genus has been known for

6142-664: The time. Neovenatorids were envisioned as the latest-surviving allosauroids, which were able to persist well into the Late Cretaceous due to their low profile and coelurosaur-like adaptations. Later studies supported this hypothesis, such as Carrano, Benson & Sampson large study of tetanuran relationships in 2012, and Zanno & Makovicky description of the newly discovered theropod Siats in 2013, which they placed within Megaraptora. Fukuiraptor and Australovenator were consistently found to be close relatives of each other; this

6225-566: The values quoted are the mean of "accepted" names alone (all "uncertain" names treated as unaccepted) and "accepted + uncertain" names (all "uncertain" names treated as accepted), with the associated range of uncertainty indicating these two extremes. Within Animalia, the largest phylum is Arthropoda , with 151,697 ± 33,160 accepted genus names, of which 114,387 ± 27,654 are insects (class Insecta). Within Plantae, Tracheophyta (vascular plants) make up

6308-399: The ventral side of the neck preserves scutes . An impression from the base of the tail preserves larger scales around 2 cm in diameter. However, it has been noted that these may be sauropod scales due to their similarity and the fact that non-theropod remains were discovered associated with the tail of this particular Allosaurus specimen. Concavenator preserves scutes on the underside of

6391-429: The virus species " Salmonid herpesvirus 1 ", " Salmonid herpesvirus 2 " and " Salmonid herpesvirus 3 " are all within the genus Salmonivirus ; however, the genus to which the species with the formal names " Everglades virus " and " Ross River virus " are assigned is Alphavirus . As with scientific names at other ranks, in all groups other than viruses, names of genera may be cited with their authorities, typically in

6474-432: Was also supported by a provisional analysis published by Andrea Cau in 2021. This publication is also the origin of the hypothesis that several "compsognathids" from Europe may have been juvenile carnosaurs. The results of this analysis differ from those of Rauhut and Pol in that Cau finds Megalosauroidea to be monophyletic and the sister-taxon of Allosauroidea within Carnosauria. An abbreviated version of this phylogeny

6557-502: Was also the case for Aerosteon and Megaraptor . Orkoraptor was a "wildcard" taxon difficult to place with certainty. Phylogenetic studies conducted by Benson, Carrano and Brusatte (2010) and Carrano, Benson and Sampson (2012) recovered the group Megaraptora and a few other taxa as members of the Neovenatoridae. This would make neovenatorids the latest-surviving allosauroids; at least one megaraptoran, Orkoraptor , lived near

6640-512: Was historically considered largely synonymous with Allosauroidea , some recent studies have revived Carnosauria as clade including both Allosauroidea and Megalosauroidea (which is sometimes recovered as paraphyletic with respect to Allosauroidea), and thus including the majority of non- coleurosaurian members of theropod clade Tetanurae . Other researchers have found Allosauroidea and Megalosauroidea to be unrelated groups. Distinctive characteristics of carnosaurs include large eye sockets ,

6723-424: Was hypothesized in a 2011 study that examined muscle scars on the bones and made inferences based on phylogenetic bracketing. 26 muscles, three ligaments, and two connective tissue structures were described. While the hypothesized muscles of Poposaurus share many aspects with those of birds, they are more similar to those of crocodilians. Poposaurus is thought to have had a puboischiotibialis muscle, but this muscle

6806-481: Was originally named by Othniel Charles Marsh , but it was given a formal definition by Phil Currie and Zhao, and later used as a stem-based taxon by Paul Sereno in 1997. Sereno was the first to provide a stem-based definition for the Allosauroidea in 1998, defining the clade as "All neotetanurans closer to Allosaurus than to Neornithes ." Kevin Padian used a node-based definition in his 2007 study which defined

6889-582: Was reclassified as a new species of Poposaurus , P. langstoni . P. langstoni differs from P. gracilis in that it is larger, it does not have a ridge of bone behind the hip socket, and does not have a pit on the ischium that fits into the ilium. In 2011, a nearly complete specimen of P. gracilis known as YPM VP 057100, and informally named "the Yale specimen", was found in the Chinle Formation of Grand Staircase–Escalante National Monument , Utah. It includes

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