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71-532: Saurolophus ( / s ɔː ˈ r ɒ l ə f ə s / ; meaning "lizard crest") is a genus of large hadrosaurid dinosaur from the Late Cretaceous period of Asia and North America , that lived in what is now the Horseshoe Canyon and Nemegt formations about 70 million to 66 million years ago. It is one of the few genera of dinosaurs known from multiple continents . The type species , S. osborni ,

142-417: A hadrosaurid , Saurolophus would have been a bipedal / quadrupedal herbivore , eating a variety of plants . Its skull permitted a grinding motion analogous to chewing , and its teeth were continually replacing and packed into dental batteries that contained hundreds of teeth, only a relative handful of which were in use at any time. Plant material would have been cropped by its broad beak, and held in

213-836: A (largely) solid crest. The following cladogram of hadrosaurid relationships was published in 2013 by Alberto Prieto-Márquez et al. in Acta Palaeontologica Polonica : Acristravus gagstarsoni Brachylophosaurus canadensis Maiasaura peeblesorum Shantungosaurus giganteus Edmontosaurus regalis Edmontosaurus annectens Kerberosaurus manakini Sabinas OTU Prosaurolophus maximus Saurolophus morrisi (now Augustynolophus ) Saurolophus osborni Saurolophus angustirostris Wulagasaurus dongi Kritosaurus navajovius Big Bend UTEP OTU Secernosaurus koerneri Willinakaqe salitralensis Gryposaurus latidens Gryposaurus notabilis Gryposaurus monumentensis As

284-405: A comprehensive enough description to compare the species with S. osborni . In 1939–40, two partial skeletons were found in the late Maastrichtian age Moreno Formation of California . These specimens were referred to cf. Saurolophus sp. In 2010, one of the skulls was instead assigned to Edmontosaurus . A 2013 study placed the two specimens in a new species, S. morrisi . In 2014, the species

355-458: A different species. If this can happen without the larger mother population also developing a new autapomorphy, then the mother population cannot remain a species under the autapomorphic species concept: it would no longer have any apomorphies not also shared by the daughter species. Phylogenetic similarities: These phylogenetic terms are used to describe different patterns of ancestral and derived character or trait states as stated in

426-407: 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

497-643: 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

568-621: 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,

639-533: A minimum size of about 2000 m2, which suggest that over 100 Saurolophus carcasses may have contributed to the event. However, they discussed that even though evidence clearly reflects a catastrophic mass-mortality of a social group of S. angustirostris and provide the first evidence of gregariousness in this taxon, the exact conditions and cause surrounding the group death can not be determined. Bell and team also noted that while Dragon's Tomb provides direct evidence for social behaviour in S. angustirostris , there

710-595: A more diverse theropod fauna. Unlike other Mongolian formations like the well-known Djadochta Formation that includes Velociraptor and Protoceratops , the Nemegt is interpreted as being a well-watered region, like the Dinosaur Park Formation in Alberta. When examined, the rock facies of the Nemegt formation suggest the presence of stream and river channels, mudflats, and shallow lakes. Sediments also indicate that

781-405: A partial fragmentary ischium from Heilongjiang , China , that Riabinin named S. kryschtofovici . Much better remains were soon recovered, though, but from Mongolia 's early Maastrichtian-age Nemegt Formation . The 1946–1949 Russian - Mongolian paleontological expeditions recovered the large skeleton that became S. angustirostris as described by Anatoly Rozhdestvensky . Other skeletons from

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852-409: 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

923-566: A rich habitat existed, offering diverse food in abundant amounts that could sustain Cretaceous dinosaurs. It coexisted with the rare hadrosaurid Barsboldia , flat-headed pachycephalosaurian Homalocephale and domed Prenocephale , the large ankylosaurid Saichania , rare titanosaurs sauropods Nemegtosaurus and Opisthocoelicaudia , the alvarezsaurid Mononykus , three types of troodontids including Zanabazar , several oviraptorosaurians including Rinchenia and Nemegtomaia ,

994-436: A single taxon, they do not convey information about relationship. Therefore, autapomorphies are not useful to infer phylogenetic relationships. However, autapomorphy, like synapomorphy and plesiomorphy is a relative concept depending on the taxon in question. An autapomorphy at a given level may well be a synapomorphy at a less-inclusive level. An example of an autapomorphy can be described in modern snakes. Snakes have lost

1065-427: 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. ;

1136-455: 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

1207-461: A variety of growth stages have also been discovered, and S. angustirostris is now the most abundant Asian hadrosaurid. Two species are regarded as valid today: the type species S. osborni , and S. angustirostris . S. osborni (Brown, 1912) is known from a skull and skeleton, two other complete skulls, and skull fragments. S. angustirostris (Rozhdestvensky, 1952) is known from at least 15 specimens. It differs from S. osborni by some details of

1278-427: Is a skull and postcrania, so the cranium of the species is well-described. Bell et al. re-evaluated the entire species in a 2011 publication with Acta Palaeontologica Polonica . Their description found the skull to be generalized among hadrosaurines, and are much larger than any skulls of S. osborni . The most unusual feature for a hadrosaurine is the long, protruding, solid crest that extends upwards diagonally from

1349-596: 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

1420-707: Is interpreted as having a significant marine influence, due to an encroaching Western Interior Seaway , the shallow sea that covered the midsection of North America through much of the Cretaceous . S. osborni may have preferred to stay inland. It lived alongside other dinosaur species including the ornithopods Hypacrosaurus altispinus and Parksosaurus warreni , ankylosaurid Anodontosaurus lambei , pachycephalosaurid Sphaerotholus edmontonense , ornithomimids Dromiceiomimus brevitertius and an unnamed species of Struthiomimus , small theropods including Atrociraptor marshalli and Albertonykus borealis , and

1491-425: Is its cranial crest, which is present in young individuals, but is smaller. It is long and spike-like and projects upward and backward at about a 45° angle, starting from over the eyes. This crest is often described as solid, but appears to be solid only at the point, with internal chambers that may have had a respiratory and/or heat-regulation function. The unique crest of Saurolophus is made up almost completely by

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1562-460: 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,

1633-474: 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

1704-490: Is useful in that it avoids non-monophyletic groupings, it has its criticisms as well. N.I. Platnick, for example, believes the autapomorphic species concept to be inadequate because it allows for the possibility of reproductive isolation and speciation while revoking the "species" status of the mother population. In other words, if a peripheral population breaks away and becomes reproductively isolated, it would conceivably need to develop at least one autapomorphy to be recognized as

1775-525: Is yet no evidence for it in S. osborni . Nevertheless, gregariousness is apparently widespread in hadrosaurines. David W.E. Hone and Mahito Watabe in 2011 reported the left humerus of a nearly complete S. angustirostris skeleton (MPC-D 100/764) from the Bügiin Tsav locality of the Nemegt Formation, which was heavily damaged from bite marks attributed to the sympatric Tarbosaurus . As suggested by

1846-621: 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

1917-799: 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;

1988-515: The Mongolian species, was larger; it got as large as 13 m (43 ft) in length, and larger remains are reported. It has been estimated to have potentially weighed up to 11 tonnes (11 long tons; 12 short tons). The largest known skull of S.angustirostris measures 1.22 m (4.0 ft) in length. Aside from size, the two species are virtually identical, with differentiation hindered by lack of study. The most distinctive feature of Saurolophus

2059-527: The Red Deer River in Alberta. Brown wasted little time in describing his material, giving it its own subfamily. Saurolophus was an important early reference for other hadrosaurs, as seen in the names of Prosaurolophus ("before Saurolophus ") and Parasaurolophus ("near Saurolophus "). However, little additional material has been recovered and described. Instead, more abundant remains from Asia have provided more data. Initial remains were not promising;

2130-414: The basilisk lizard . Peter Dodson interpreted similar features in other duckbills as having use in sexual identification. Maryańska and Osmólska, noting the hollow base, suggested that the crest increased the surface area of the respiratory cavity, and helped in thermoregulation. James Hopson supported a function as a visual signal, and further mentioned the possibility that the inflatable skin flaps over

2201-419: 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 ,

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2272-664: The ornithomimosaurs Anserimimus and Gallimimus , and the giant theropods Deinocheirus and Therizinosaurus , including the tyrannosaurid Tarbosaurus . S. angustirostris was common, and would have been an important large herbivore in the Nemegt Formation. By comparison, S. osborni was rare in the Horseshoe Canyon Formation, and faced competition from other duckbills (genus Hypacrosaurus ). [REDACTED] Data related to Saurolophus at Wikispecies [REDACTED] [REDACTED] [REDACTED] [REDACTED] Genus The composition of

2343-404: 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,

2414-496: The tyrannosaurid Albertosaurus sarcophagus . The dinosaurs from this formation form part of the Edmontonian land vertebrate age. A 2001 study suggested that Saurolophus osborni was part of a distinct inland fauna characterized by an association between Anchiceratops ornatus and it, while the contemporary coastal fauna was characterized by the association of Pachyrhinosaurus canadensis and Edmontosaurus regalis . However,

2485-597: The association between S. osborni and Anchiceratops was later noted to be in error, Anchiceratops only occurs lower in the Horseshoe Canyon Formation, before the major transgression of the Western Interior Seaway represented by the Drumheller Marine Tongue. S. angustirostris was one of the largest herbivores of the Nemegt Formation , which lacked large ceratopsians , but had sauropods and

2556-407: The back of the skull roof. Unlike lambeosaurines , the crests are made up completely of the nasal bone . The premaxilla bones make up almost 50% of the entire skull length, and both sides are filled with small holes. Only in adult individuals has the front of the premaxillary contact been fused. Longer than the premaxilla, the nasal bones are the longest in the skull. They make up the entire length of

2627-442: 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

2698-452: The basis of amount of divergence associated with reproductive incompatibility, which is measured essentially by number of autapomorphies. This grouping method is often referred to as the " monophyletic species concept" or the "phylospecies" concept and was popularized by D.E. Rosen in 1979. Within this definition, a species is seen as "the least inclusive monophyletic group definable by at least one autapomorphy". While this model of speciation

2769-517: The crest, and are never preserved as fused. Barnum Brown, who described the first specimens, put it in its own subfamily in "Trachodontidae" (=Hadrosauridae), the Saurolophinae. At the time, this also included Corythosaurus and Hypacrosaurus , the only well-known examples of what would become the Lambeosaurinae . Brown thought that Saurolophus had an expanded tip to the ischium bone in

2840-486: The deltopectoral crest, suggesting that this Tarbosaurus was actively selecting which biting style employ to scavenge the bone. Comparisons between the scleral rings of Saurolophus and modern birds and reptiles suggest that it may have been cathemeral , active throughout the day at short intervals. S. osborni is known only from the upper part (unit 4) of the Horseshoe Canyon Formation . The formation

2911-426: The earliest developmental stage at the time of their deaths. Based on these juveniles, Dewaele and team indicated that during the ontogeny of S. angustirostris the distinct crest found in adults was poorly developed in infancy, the snout grew proportionally longer, the orbit became more oval-shaped, the doming of the frontal became less prominent, and the coronoid process became higher. Bell and team in 2018 described

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2982-508: The famous Dragon's Tomb assambleage of the Altan Uul II locality, Nemegt Formation, which contains a large-sized bonebed of S. angustirostris . This bonebed is largely monodominant (one dominant species), with at least three size-classes (juveniles, subadults, and adults) of S. angustirostris . Examinations made to Dragon's Tomb suggest that at least 21 Saurolophus individuals can be currently found. The team indicated that this bonebed has

3053-609: The first described remains of Saurolophus in 1911, including a nearly complete skeleton ( AMNH 5220 ). Now on display in the American Museum of Natural History, this skeleton was the first nearly complete dinosaur skeleton from Canada. It was found in rocks of early Maastrichtian age, in the Upper Cretaceous Horseshoe Canyon Formation (then known as the Edmonton Formation) near Tolman Ferry on

3124-446: The focal taxon (which may be a species , family or in general any clade). It can therefore be considered an apomorphy in relation to a single taxon. The word autapomorphy , introduced in 1950 by German entomologist Willi Hennig , is derived from the Greek words αὐτός, autos "self"; ἀπό, apo "away from"; and μορφή, morphḗ = "shape". Because autapomorphies are only present in

3195-446: 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

3266-727: 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,

3337-411: The hip, as dinosaurs now recognized as lambeosaurines had, but this appears to have been based on a mistakenly associated lambeosaurine ischium. Additionally, he misinterpreted the crests of Saurolophus and lambeosaurines as being made of the same bones. Most publications before 2010 classified Saurolophus as a member of Hadrosaurinae, often known colloquially as the "flat-headed hadrosaurs". In 2010,

3408-431: The jaws by a cheek -like organ. Its feeding range would have extended from the ground to about 4 m (13 ft) above. The distinctive spike-like crest of Saurolophus has been interpreted in multiple ways, and could have had multiple functions. Brown compared it to the crest of a chameleon , and suggested it could provide an area for muscle attachment and a connection point for a nonbody back frill like that seen in

3479-534: The lack of damage to the rest of the skeleton (such as large wounds in skeletal remains indicative of predation ), this tyrannosaurid was likely scavenging an already dead S. angustirostris . It is unlikely that a large-bodied predator such as Tarbosaurus would have left sparse feeding traces on a single humerus having an entire carcass to feed on. The humerus shows three distinctive feeding methods, interpreted as punctures, drag marks, and bite−and−drag marks. Hone and Watabe noted that bite marks were mostly located at

3550-628: 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,

3621-450: 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. Autapomorphies In phylogenetics , an autapomorphy is a distinctive feature, known as a derived trait, that is unique to a given taxon. That is, it is found only in one taxon , but not found in any others or outgroup taxa , not even those most closely related to

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3692-403: 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

3763-432: The name antedates S. angustirostris ). Until a 2011 reevaluation of the species by Phil R. Bell , S. angustirostris was not well-described. No autapomorphies , unique derived traits, had been established distinguishing it from S. osborni . Bell found in a publication earlier in the year that the two previous studies of S. angustirostris , by Rozhdestvensky in 1952, and Maryanska and Osmolska in 1981, do not provide

3834-428: 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

3905-436: The nasal bones, and in S. angustirostris it is solid. In adult specimens the crests are a rounded triangular shape in cross section. The crest protrudes past the edge of the skull backwards. Thin processes from the frontals and prefrontals extend along the underside of the crest, probably to strengthen it. At the end of the crest is a swelling of the nasal, which is often termed differently. The holotype of S. angustirostris

3976-435: The nostrils could have acted as resonators and additional visual signals. This idea has been picked up by authors of popular dinosaur works, such as David B. Norman , who discussed hadrosaurid display at length and included a life restoration of such an adaptation in action. In 2015 Leonard Dewaele and colleagues described a small and partial nest containing several juveniles of S. angustirostris . The specimen (MPC-D 100/764)

4047-526: 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

4118-466: 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

4189-401: The scales on the tail flank were arranged in vertical patterns, which may have corresponded to striped coloration in life. This area was covered in radial scale patterns in S. osborni , possibly indicating a more mottled or spotted coloration. S. kryschtofovici (Riabinin, 1930) is not considered valid; either it is regarded as a dubious name, or as a synonym of S. angustirostris (although

4260-408: 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

4331-425: The skull, as well as in the pattern of scales found in skin impressions. The Mongolian species had a longer skull (by 20%) and the front of the snout (the premaxillary bones) were more upwardly directed. S. angustirostris also had a distinctive row of rectangular scales along the midline of the back and tail, known as 'midline feature-scales'; these are not currently preserved in S. osborni . In S. angustirostris ,

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4402-497: 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,

4473-412: 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

4544-420: The subfamily Saurolophinae was brought back into use because Hadrosaurus appears to have branched off prior to the "hadrosaurine"–lambeosaurine split. As a result, Hadrosaurinae by definition cannot include the traditional "hadrosaurines". Saurolophinae is the oldest available name for the former "hadrosaurine" clade . Saurolophus , as the name suggests, is a saurolophine, as it has a saurolophine pelvis and

4615-403: 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

4686-477: The two pairs of legs that characterize all of Tetrapoda , and the closest taxa to Ophidia – as well as their common ancestors – all have two pairs of legs. Therefore, the Ophidia taxon presents an autapomorphy with respect to its absence of legs. The autapomorphic species concept is one of many methods that scientists might use to define and distinguish species from one another. This definition assigns species on

4757-566: 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

4828-429: 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

4899-443: Was described by Barnum Brown in 1912 from Canadian fossils. A second valid species, S. angustirostris , is represented by numerous specimens from Mongolia , and was described by Anatoly Konstantinovich Rozhdestvensky . Saurolophus is distinguished by a spike-like crest which projects up and back from the skull. It was a herbivorous dinosaur which could move about either bipedally or quadrupedally . Barnum Brown recovered

4970-429: Was reassigned to a new genus, Augustynolophus . Saurolophus is known from material including nearly complete skeletons, giving researchers a clear picture of its bony anatomy. S. osborni , the rarer Albertan species, was around 8.2–8.5 m (27–28 ft) long, with its skull 1.0 m (3.3 ft) long. It has been estimated to have weighed around 3 tonnes (3.0 long tons; 3.3 short tons). S. angustirostris ,

5041-399: Was recovered from the notorious Dragon's Tomb assambleage of the Nemegt Formation. The team noted that among remains, three or even four juveniles can be recognized, and two fragmentary eggshells were found in association. Juveniles within this block were identified as perinates , as they had skull lengths less than five percent of the length of the skulls of the adults, indicating they were in

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