''Hypsirhophus'' (meaning "high roof"; often misspelled "''Hypsirophus''") is a

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 ...

stegosauria Stegosauria is a group of Herbivore, herbivorous ornithischian dinosaurs that lived during the Jurassic and early Cretaceous Period (geology), periods. Stegosaurian fossils have been found mostly in the Northern Hemisphere (North America, Europe a ...

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutio ...

s. It contains a single

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

, ''Hypsirhophus discurus'', which is known only from a fragmentary specimen. The

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

consists of partial vertebrae from the back, three from the

tail The tail is the elongated section at the rear end of a bilaterian animal's body; in general, the term refers to a distinct, flexible appendage extending backwards from the midline of the torso. In vertebrate animals that evolution, evolved to los ...

, and a piece of

rib In vertebrate anatomy, ribs () are the long curved bones which form the rib cage, part of the axial skeleton. In most tetrapods, ribs surround the thoracic cavity, enabling the lungs to expand and thus facilitate breathing by expanding the ...

History and classification

The first described fossils of ''Hypsirhophus discurus'' were unearthed by schoolteacher Oramel William Lucas who working for

Edward Drinker Cope Edward Drinker Cope (July 28, 1840 – April 12, 1897) was an American zoologist, paleontology, paleontologist, comparative anatomy, comparative anatomist, herpetology, herpetologist, and ichthyology, ichthyologist. Born to a wealthy Quaker fam ...

at Cope's Quarry 3 near "Cope's Nipple" at Garden Park, a fossil site 3.8 miles northeast of Canon City,

Colorado Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...

, and came from the

Tithonian In the geological timescale, the Tithonian is the latest age (geology), age of the Late Jurassic Epoch and the uppermost stage (stratigraphy), stage of the Upper Jurassic Series. It spans the time between 149.2 ±0.7 annum, Ma and 143.1 ±0.6 (mi ...

strata of the

Upper Jurassic The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 161.5 ± 1.0 to 143.1 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic strata.Owen 1987. In European lithostratigraphy, the name ...

. The fossils now accepted as ''Hypsirhophus'' were fragmentary and came from one individual, containing: a dorsal vertebra, 2 partial neural spines, 2 caudal

vertebral centra Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spinal ...

, and a

fragment. These fossils were then sent to Cope, who briefly described them in 1878 as part of the

Bone Wars The Bone Wars, also known as the Great Dinosaur Rush, was a period of intense and ruthlessly competitive fossil hunting and discovery during the Gilded Age of American history, marked by a heated rivalry between Edward Drinker Cope (of the Aca ...

, a competition between Cope and the

Yale Yale University is a private Ivy League research university in New Haven, Connecticut, United States. Founded in 1701, Yale is the third-oldest institution of higher education in the United States, and one of the nine colonial colleges ch ...

paleontologist

Othniel Charles Marsh Othniel Charles Marsh (October 29, 1831 – March 18, 1899) was an American professor of paleontology. A prolific fossil collector, Marsh was one of the preeminent paleontologists of the nineteenth century. Among his legacies are the discovery or ...

over fossils from the

American West The Western United States (also called the American West, the Western States, the Far West, the Western territories, and the West) is census regions United States Census Bureau As American settlement in the U.S. expanded westward, the mea ...

.Cope, E. D. (1879). New Jurassic Dinosauria. ''American Naturalist'', ''13'', 402-404. Cope incorrectly grouped a

theropod Theropoda (; from ancient Greek , (''therion'') "wild beast"; , (''pous, podos'') "foot"">wiktionary:ποδός"> (''pous, podos'') "foot" is one of the three major groups (clades) of dinosaurs, alongside Ornithischia and Sauropodom ...

femur, possibly from ''

Allosaurus ''Allosaurus'' ( ) is an extinct genus of theropod dinosaur that lived 155 to 145 million years ago during the Late Jurassic period ( Kimmeridgian to late Tithonian ages). The first fossil remains that could definitively be ascribed to th ...

'', found nearby into the specimen causing him to believe it was a theropod related to '' Laelaps'' or ''

Megalosaurus ''Megalosaurus'' (meaning "great lizard", from Ancient Greek, Greek , ', meaning 'big', 'tall' or 'great' and , ', meaning 'lizard') is an extinct genus of large carnivorous theropod dinosaurs of the Middle Jurassic Epoch (Bathonian stage, 166 ...

'' and possibly even synonymous with a species of the former that he described, ''Laelaps trihedrodon''.Cope, E. D. (1878). A new genus of Dinosauria from Colorado. ''American Naturalist'', ''12'', 181. The generic name of ''Hypsirhophus'' means "high roof" after the tall anatomy of the dorsal vertebrae, while the specific name hasn't been translated. The next year in 1879, Cope named another species, ''Hypsirhophus'' "seeleyanus", based on several vertebrae, limb bones, and teeth from an unknown locality in Colorado that have since been lost, but were theropod fossils instead of stegosaurian. Cope also inadequately named the species, making it a nomen nudum. The holotype of ''Hypsirhophus discurus'' was transferred to the American Museum of Natural History after Cope's death in 1897, now catalogued under specimen number

AMNH The American Museum of Natural History (AMNH) is a natural history museum on the Upper West Side of Manhattan in New York City. Located in Theodore Roosevelt Park, across the street from Central Park, the museum complex comprises 21 interco ...

5731. It was not until many years later and the descriptions of complete ''Stegosaurus'' skeletons that ''Hypsirhophus'' was classified as a stegosaur, with Cope's rival Marsh placing ''Hypsirhophus'' in Stegosauridae in 1892.Marsh, O. C. (1896)
''The dinosaurs of North America''.
US Government Printing Office. Some later researchers have considered ''Hypsirhophus'' to be a synonym of ''

Stegosaurus ''Stegosaurus'' (; ) is a genus of herbivorous, four-legged, armored dinosaur from the Late Jurassic, characterized by the distinctive kite-shaped upright plates along their backs and spikes on their tails. Fossils of the genus have been fo ...

'', or 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 ...

'', though

Kenneth Carpenter Kenneth Carpenter (born 21 September 1949) is an American paleontologist. He is the former director of the USU Eastern Prehistoric Museum and author or co-author of books on dinosaurs and Mesozoic life. His main research interests are armore ...

and Peter Galton have suggested that it is distinct and valid based on differences in the vertebrae.

Description

Due to the fragmentary nature of the type specimen, lack of description, and the single known specimen, little is known from ''Hypsirhophus.''

noted that it could be diagnosed by: Circular fossa between postzygapophyses in ''Hypsirhophus'' versus vertical grooves in ''Stegosaurus,'' a median ridge extending from base of postzygapophyses to

neural canal In the developing chordate (including vertebrates), the neural tube is the embryonic precursor to the central nervous system, which is made up of the brain and spinal cord. The neural groove gradually deepens as the neural folds become elevated, ...

versus no ridge groove in ''Stegosaurus ungulatus'' (as ''S. stenops'') and in cross-section of pedicel, the anterior surface is convex versus being concave in ''Stegosaurus.'' The

dorsal vertebrae In vertebrates, thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. In humans, there are twelve thoracic vertebra (anatomy), vertebrae of intermediate size between the ce ...

are very tall, at 47 centimeters tall despite being incomplete and some of the largest dorsals known.

References

{{Taxonbar, from=Q15723432 Stegosauria Dinosaur genera Tithonian dinosaurs Morrison Formation Fossil taxa described in 1878 Taxa named by Edward Drinker Cope Dinosaurs of the United States