Gargoyleosaurus Temporal range: Late Jurassic, | |
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Fossil skeleton, Denver Museum of Nature and Science | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | † Ornithischia |
Clade: | † Thyreophora |
Clade: | † Ankylosauria |
Family: | † Nodosauridae |
Genus: | † Gargoyleosaurus Carpenter et al. 1998 |
Species: | †G. parkpinorum |
Binomial name | |
†Gargoyleosaurus parkpinorum Carpenter et al. 1998 | |
Gargoyleosaurus (meaning "gargoyle lizard") is one of the earliest ankylosaurs known from reasonably complete fossil remains. The holotype was discovered in 1995 at the Bone Cabin Quarry West locality, in Albany County, Wyoming in exposures of the Upper Jurassic (Kimmeridgian to Tithonian stages) Morrison Formation. [1]
The type species, G. parkpinorum (originally G. parkpini) was described by Ken Carpenter et al. in 1998. A mounted skeletal reconstruction of Gargoyleosaurus parkpinorum can be seen at the Denver Museum of Nature and Science and, alongside a couple skeletons of baby Stegosaurus , has been on display there since around 2002. Gargoyleosaurus was present in stratigraphic zone 2 of the Morrison Formation. [2]
The holotype specimen of Gargoyleosaurus parkpinorum was collected by Western Paleontology Labs in 1995 and is currently held in the collections of the Denver Museum of Nature and Science, Denver, Colorado. Besides the holotype, two other partial skeletons are known (although not yet described). The holotype consists of most of the skull and a partial postcranial skeleton. The specimen was originally described as Gargoyleosaurus parkpini by Carpenter, Miles and Cloward in 1998, then renamed G. parkpinorum by Carpenter et al. in 2001, in accordance with ICZN art. 31.1.2A.
Gargoyleosaurus was a relatively small ankylosaur, reaching 3–3.5 m (9.8–11.5 ft) in length and 300–754 kg (661–1,662 lb) in body mass. [3] [4] [5] Much of the skull and skeleton has been recovered, and the taxon displays cranial sculpturing, including pronounced deltoid quadratojugal and squamosal bosses. The taxon is further characterized by a narrow rostrum (in dorsal view), the presence of seven conical teeth in each premaxilla, an incomplete osseous nasal septum, a linearly arranged nasal cavity, the absence of an osseus secondary palate, and, as regards osteoderms, two sets of co-ossified cervical plates and a number of elongate conical spines. [1] A very unusual feature is the sagittal (midline) osteoderm on the first set of cervical plates; in most other ankylosaurs, these osteoderms are bilateral, i.e. paired with one on each side of the midline. [3]
Vickaryous et al. (2004) place Gargoyleosaurus parkpinorum within the family Ankylosauridae of the Ankylosauria and are in agreement with most previous phylogenetic hypotheses, which place the genus as the sister group to all other ankylosaurids (i.e., members of the Ankylosauridae). These studies however, only utilized the skull, whereas many of the distinctive features of the family Polacanthidae are in the postcranial skeleton. In contrast, a phylogenetic analysis by Soto-Acuña and colleagues in 2021 recovered Gargoyleosaurus as a nodosaurid.
Below is a reproduced phylogenetic analysis from Soto-Acuña et al. (2021): [6]
Ankylosauria is a group of herbivorous dinosaurs of the clade Ornithischia. It includes the great majority of dinosaurs with armor in the form of bony osteoderms, similar to turtles. Ankylosaurs were bulky quadrupeds, with short, powerful limbs. They are known to have first appeared in the Middle Jurassic, and persisted until the end of the Cretaceous Period. The two main families of Ankylosaurs, Nodosauridae and Ankylosauridae are primarily known from the Northern Hemisphere, but the more basal Parankylosauria are known from southern Gondwana during the Cretaceous.
Edmontonia is a genus of panoplosaurin nodosaurid dinosaur from the Late Cretaceous Period. It is part of the Nodosauridae, a family within Ankylosauria. It is named after the Edmonton Formation, the unit of rock where it was found.
Gastonia is a genus of herbivorous ankylosaurian dinosaur from the Early Cretaceous of North America, around 139 to 134.6 million years ago. It is often considered a nodosaurid closely related to Polacanthus. Gastonia has a sacral shield and large shoulder spikes.
Aletopelta is a monospecific genus of basal ankylosaurid dinosaur from Southern California that lived during the Late Cretaceous in what is now the Point Loma Formation. The type and only species, Aletopelta coombsi, is known from a partial skeleton preserving osteoderms. It was originally described in 1996 by W. P. Coombs, Jr. and T.A. Deméré before being named in 2001 by Tracy Ford and James Kirkland. Aletopelta has an estimated size of 5 metres and weight of 2 tonnes. The holotype formed a miniature reef and was scavenged upon by invertebrates and sharks.
Nodosauridae is a family of ankylosaurian dinosaurs known from the Late Jurassic to the Late Cretaceous periods in what is now Asia, Europe, North America, and possibly South America. While traditionally regarded as a monophyletic clade as the sister taxon to the Ankylosauridae, some analyses recover it as a paraphyletic grade leading to the ankylosaurids.
Shamosaurus is an extinct genus of herbivorous basal ankylosaurid ankylosaur from Early Cretaceous deposits of Höövör, Mongolia.
Stegopelta is a genus of struthiosaurin nodosaurid dinosaur. It is based on a partial skeleton from the latest Albian-earliest Cenomanian-age Lower and Upper Cretaceous Belle Fourche Member of the Frontier Formation of Fremont County, Wyoming, USA.
Texasetes is a genus of ankylosaurian dinosaurs from the late Lower Cretaceous of North America. This poorly known genus has been recovered from the Paw Paw Formation near Haslet, Tarrant County, Texas, which has also produced the nodosaurid ankylosaur Pawpawsaurus.
Cedarpelta is an extinct genus of basal ankylosaurid dinosaur from Utah that lived during the Late Cretaceous period in what is now the Mussentuchit Member of the Cedar Mountain Formation. The type and only species, Cedarpelta bilbeyhallorum, is known from multiple specimens including partial skulls and postcranial material. It was named in 2001 by Kenneth Carpenter, James Kirkland, Don Burge, and John Bird. Cedarpelta has an estimated length of 7 metres and weight of 5 tonnes (11,023 lbs). The skull of Cedarpelta lacks extensive cranial ornamentation and is one of the only known ankylosaurs with individual skull bones that are not completely fused together.
Mymoorapelta is a nodosaurid ankylosaur from the Late Jurassic Morrison Formation of western Colorado and central Utah, USA. The animal is known from a single species, Mymoorapelta maysi, and few specimens are known. The most complete specimen is the holotype individual from the Mygatt-Moore Quarry, which includes osteoderms, a partial skull, vertebrae, and other bones. It was initially described by James Kirkland and Kenneth Carpenter in 1994. Along with Gargoyleosaurus, it is one of the earliest known nodosaurids.
Denversaurus is a genus of panoplosaurin nodosaurid dinosaur from the late Maastrichtian of Late Cretaceous Western North America. Although at one point treated as a junior synonym of Edmontonia by some taxonomists, current research indicates that it is its own distinct nodosaurid genus.
Gobisaurus is an extinct genus of herbivorous basal ankylosaurid ankylosaur from the Upper Cretaceous of China. The genus is monotypic, containing only the species Gobisaurus domoculus.
Panoplosaurus is a genus of armoured dinosaur from the Late Cretaceous of Alberta, Canada. Few specimens of the genus are known, all from the middle Campanian of the Dinosaur Park Formation, roughly 76 to 75 million years ago. It was first discovered in 1917, and named in 1919 by Lawrence Lambe, named for its extensive armour, meaning "well-armoured lizard". Panoplosaurus has at times been considered the proper name for material otherwise referred to as Edmontonia, complicating its phylogenetic and ecological interpretations, at one point being considered to have existed across Alberta, New Mexico and Texas, with specimens in institutions from Canada and the United States. The skull and skeleton of Panoplosaurus are similar to its relatives, but have a few significant differences, such as the lumpy form of the skull osteoderms, a completely fused shoulder blade, and regularly shaped plates on its neck and body lacking prominent spines. It was a quadrupedal animal, roughly 5 m (16 ft) long and 1,600 kg (3,500 lb) in weight. The skull has a short snout, with a very domed surface, and bony plates directly covering the cheek. The neck had circular groups of plates arranged around the top surface, both the forelimb and hindlimb were about the same length, and the hand may have only included three fingers. Almost the entire surface of the body was covered in plates, osteoderms and scutes of varying sizes, ranging from large elements along the skull and neck, to smaller, round bones underneath the chin and body, to small ossicles that filled in the spaces between other, larger osteoderms.
Tarchia is a genus of herbivorous ankylosaurid dinosaur from the late Cretaceous of Mongolia.
Talarurus is a genus of ankylosaurid dinosaur that lived in Asia during the Late Cretaceous period, about 96 million to 89 million years ago. The first remains of Talarurus were discovered in 1948 and later described by the Russian paleontologist Evgeny Maleev with the type species T. plicatospineus. It is known from multiple yet sparse specimens, making it one of the most well known ankylosaurines, along with Pinacosaurus. Elements from the specimens consists of various bones from the body; five skulls have been discovered and assigned to the genus, although the first two were very fragmented.
Palaeoscincus is a dubious genus of ankylosaurian dinosaur based on teeth from the mid-late Campanian-age Upper Cretaceous Judith River Formation of Montana. Like several other dinosaur genera named by Joseph Leidy, it is an historically important genus with a convoluted taxonomy that has been all but abandoned by modern dinosaur paleontologists. Because of its wide use in the early 20th century, it was somewhat well known to the general public, often through illustrations of an animal with the armor of Edmontonia and the tail club of an ankylosaurid.
Dracopelta is a monospecific genus of ankylosaur dinosaur from Portugal that lived during the Late Jurassic in what is now the Lourinhã Formation. The type and only species is Dracopelta zbyszewskii, which is represented by a partial skeleton including unpublished material.
Antarctopelta is a genus of ankylosaurian dinosaur, a group of large, quadrupedal herbivores, that lived during the Maastrichtian stage of the Late Cretaceous period on what is now James Ross Island, Antarctica. Antarctopelta is the only known ankylosaur from Antarctica and a member of Parankylosauria. The only described specimen was found in 1986, the first dinosaur to be found on the continent, by Argentine geologists Eduardo Olivero and Robert Scasso. The fossils were later described in 2006 by paleontologists Leonardo Salgado and Zulma Gasparini, who named the type species A. oliveroi after Olivero.
Tanycolagreus is a genus of coelurosaurian theropod from the Late Jurassic of North America.
Kunbarrasaurus is an extinct genus of small ankylosaurian dinosaur from the Cretaceous of Australia. The genus contains a single species, K. ieversi.