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Ceratopsipes goldenensis Lockley & Hunt, 1995 - ceratopsian dinosaur trackway in the Cretaceous of Colorado, USA. Ceratopsians are the "horned dinosaurs". They were large, quadrupedal, herbivorous dinosaurs having a beaked skull and a frill - an extension of bone behind the skull that partially covered the neck. Ceratopsian dinosaurs are known from the Jurassic and Cretaceous. The last members of the group died out at the Cretaceous-Tertiary boundary, 65 million years ago. Seen here is a ceratopsian dinosaur trackway. Ceratopsian footprints are very rare. The best examples are in Colorado's Laramie Formation, a nonmarine, coastal plain to deltaic succession of mostly mixed siliciclastic sedimentary rocks - sandstones, siltstones, claystones, and coals. The footprints here consist of convex bulges on the basal surfaces of structurally-tilted sandstone beds. The ichnospecies Ceratopsipes goldenensis was named based on footprints at this locality. The trackmaker was very likely Triceratops, the # 1 most famous ceratopsian dinosaur. From on-site signage: Triceratops Tracks Several tracks of Triceratops, or a closely related horned dinosaur were first discovered in this area and named Ceratopsipes goldenensis (meaning tracks of a horned dinosaur from Golden). By happy coincidence, the first Triceratops known to science also comes from the greater Denver area near 13th Avenue and Federal Blvd. Growing to a length of almost 25 feet, Triceratops and other members of the horned dinosaur family were herbivorous animals that roamed in herds. Their trademark horns and frills that covered their necks probably served for defense. A replica Triceratops skull is on display in the clubhouse at the Fossil Trace Golf Club. These tracks (identified by small signs) help us understand that Triceratops walked with a narrow gait and erect front limbs than with a wide, sprawling gait as previously depicted. In 1887, the first Triceratops bones known to science were also discovered locally at a site near 13th Avenue and Federal Boulevard in Denver. Nearby one may see many other traces of life such as burrows, probably made by invertebrates and impressions of plant debris. Note that you are looking at all tracks and traces from the underside - in negative aspect - what one might call a worm’s eye view. All of these trace fossils indicate that the Golden area once had a warm, temperate to subtropical climate. Classification: Animalia, Chordata, Vertebrata, Reptilia, Archosauria, Dinosauria, Ornithischia, Marginocephalia, Ceratopsia, Ceratopsidae Stratigraphy: Laramie Formation, Maastrichtian Stage, upper Upper Cretaceous Locality: outcrop along Triceratops Trail, Parfet Prehistoric Preserve, southern side of the town of Golden, Colorado, USA (~vicinity of 39° 44' 35.24" North latitude, 105° 13’ 09.69" West longitude) Some info. from: Lockley & Hunt (1995) - Ceratopsid tracks and associated ichnofauna from the Laramie Formation (Upper Cretaceous: Maastrichtian) of Colorado. Journal of Vertebrate Paleontology 15: 592-614.

Skeletal reconstruction of Yuxisaurus kopchicki showing some of the main preserved elements from the holotype (highlighted in blue), with details of the skull bones (A), cervical vertebrae (B), dorsal vertebrae (C), left scapula (D), right humerus (E), and left femur (F). Scale bars equal 5 cm (A–C) or 10 cm (D–F). The facial region and distal scapula are mirrored. Osteoderms have been omitted for convenience.

Skeleton outline of Dracoraptor hanigani. Bones highlighted green for present, orange for external moulds and blue for tentatively identified bones. Many unidentified or uncertain elements have been omitted.

Dinosaur National Monument is a United States National Monument located on the southeast flank of the Uinta Mountains on the border between Colorado and Utah at the confluence of the Green and Yampa Rivers. Although most of the monument area is in Moffat County, Colorado, the Dinosaur Quarry is located in Utah just to the north of the town of Jensen, Utah. The nearest communities are Jensen, Utah, and Dinosaur, Colorado. The park contains over 800 paleontological sites and has fossils of dinosaurs including Allosaurus, Deinonychus, Abydosaurus (a nearly complete skull, lower jaws and first four neck vertebrae of the specimen DINO 16488 found here at the base of the Mussentuchit Member of the Cedar Mountain Formation is the holotype for the description) and various long-neck, long-tail sauropods. It was declared a National Monument on October 4, 1915. The rock layer enclosing the fossils is a sandstone and conglomerate bed of alluvial or river bed origin known as the Morrison Formation from the Jurassic Period some 150 million years old. The dinosaurs and other ancient animals were carried by the river system which eventually entombed their remains in Utah. The pile of sediments were later buried and lithified into solid rock. The layers of rock were later uplifted and tilted to their present angle by the mountain building forces that formed the Uintas during the Laramide orogeny. The relentless forces of erosion exposed the layers at the surface to be found by paleontologists. The dinosaur fossil beds (bone beds) were discovered in 1909 by Earl Douglass, a paleontologist working and collecting for the Carnegie Museum of Natural History. He and his crews excavated thousands of fossils and shipped them back to the museum in Pittsburgh, Pennsylvania for study and display. President Woodrow Wilson proclaimed the dinosaur beds as Dinosaur National Monument in 1915. The monument boundaries were expanded in 1938 from the original 80-acre (320,000 m2) tract surrounding the dinosaur quarry in Utah, to its present extent of over 200,000 acres (800 km²) in Utah and Colorado, encompassing the spectacular river canyons of the Green and Yampa. Though lesser-known than the fossil beds, the petroglyphs in Dinosaur National Monument are another treasure the monument holds. Due to problems with vandals, many of the sites are not listed on area maps. The "Wall of Bones" located within the Dinosaur Quarry building in the park consists of a steeply tilted (67° from horizontal) rock layer which contains hundreds of dinosaur fossils. The enclosing rock has been chipped away to reveal the fossil bones intact for public viewing. In July 2006, the Quarry Visitor Center was closed due to structural problems that since 1957 had plagued the building because it was built on unstable clay. The decision was made to build a new facility elsewhere in the monument to house the visitor center and administrative functions, making it easier to resolve the structural problems of the quarry building while still retaining a portion of the historic Mission 66 era exhibit hall. It was announced in April 2009 that Dinosaur National Monument would receive $13.1 million to refurbish and reopen the gallery as part of the Obama administration's $750 billion stimulus plan. The Park Service successfully rebuilt the Quarry Exhibit Hall, supporting its weight on 70-foot steel micropile columns that extend to the bedrock below the unstable clay. The Dinosaur Quarry was reopened in Fall 2011. en.wikipedia.org/wiki/Dinosaur_National_Monument en.wikipedia.org/wiki/Wikipedia:Text_of_Creative_Commons_...

Reconstruction of Tuebingosaurus maierfritzorum gen. et sp. nov. as a quadruped dinosaur, using the outline of Riojasaurus as a base ‒ next to the silhouette of Friedrich von Huene. The drawing of the bones is based on and modified from the original illustrations of specimen “GPIT IV” in von Huene (1932, pl. 38) that have been replicated in the literature. The right fibula is marked in grey as it was found nearby with similar measurements to the left fibula and has been assumed to be part of the same individual.

Holotype fossils of Glacialisaurus (PR 1823); metatarsals, tibia, fibula, ankle bones

Right dentary in (A), medial; (B), dorsal; and (C) lateral views. Dashed black lines represent approximate contours of the missing areas. Dashed red lines indicate the distinctive banding pattern in the opal used to estimate the extent of the missing area. (D–F) Three-dimensional renders of the posterior dentary fragment in (D) lingual view showing erupted (blue) and developing germ teeth (pink); (E) Same as (D) but with dentary removed; (F) dorsal (occlusal) view of tooth row. (G-J) Three-dimensional render of the best-preserved tooth in (G) mesial, (H) lingual, (I) distal, and (J) labial views. (K) MicroCT scan of the posterior dentary fragment in axial view showing preservation of cancellous bone. Abbreviations: cab, cancellous bone; cr, tooth crown. Photo credit: Phil Bell.

Caririchnium leonardii - dinosaur track from the Cretaceous of Colorado, USA. (replica; public display, Red Rocks Amphitheater visitor center, west of Denver, Colorado, USA) Dinosaur Ridge, Colorado has numerous dinosaur fossils, including bones and tracks. The most common track type at the site is Caririchnium leonardii, which was made by an iguanodontid dinosaur. The large, wide, three-toed print was produced by a hindfoot. Stratigraphy: Dakota Sandstone, upper Lower Cretaceous Provenance: eastern side of Dinosaur Ridge, Dakota Hogback, west of Denver, north-central Colorado, USA

Skeleton of Yamaceratops dorngobiensis (MPC-D 100/553) in right dorsolateral view. (A) Photograph; (B) Interpretive drawing. Bones are bounded by solid lines and colored beige; the matrix is gray. Shaded areas represent the broken surface of bones. Abbreviations: cd, caudal vertebrae; dr, dorsal ribs; dv, dorsal vertebrae; f, femur; fi, fibula; h, humerus; L, bone on the left side; p, isolated parietal; pp, pedal phalanges; R, bone on the right side; ra, radius; sk, skull; sv, sacral vertebrae; ti, tibia; u, ulna; il, ilium; is, ischium.

Alvarezsauroid theropod Linhenykus monodactylus Xu, Sullivan, Pittman, Choiniere, Hone, Upchurch, Tan, Xiao, Tan, and Han, 2011a, Bayan Mandahu (“Gate Locality”), Late Cretaceous (Campanian), holo−type (IVPP V17608). Skeletal silhouette showing preserved bones (missing portions shown in grey).

Figure 1, 1a. Outer and oral aspects of the imperfect dentary bone of Sarcolestes Leedsi, from the Oxford Clay of Peterborough. 2/3 nat size. s = symphysis. Figure 1b. A single tooth of the former. 3/1 nat size. Figure 2, 2a. Outer aspect and quadratic cavity of the hinder region of the same jaw. 2/3 nat size. Figure 3. A single tooth of Priodontognathus Phillipsi, 3/1 nat size, shown for purposes of comparison. Specimen in the Woodwardian Museum, Cambridge.

An Ankylosaurus head (cast of specimen AMNH 5214), on display at the Museum of the Rockies in Bozeman, Montana. This is from a specimen collected in Custer County, Montana. The Ankylosauria were armored dinosaurs that lived from 122 million years ago to 66 million years ago in western North America, Europe, and East Asia. There were two subgroups: The Nodosauridae and Ankylosauridae. The Ankylosauridae contained six species, and a single subfamily -- the Ankylosaurinae. There 18 genus within the subfamily, of which Ankylosaurus is the best known. Ankylosaurus as the last of these, and lived 65.5 to 66.5 million years ago. Ankylosaurus was about 20.5 feet long, 5 feet wide, and 5.5 feet tall at the hip. It walked on all fours, with the rear legs longer than the front ones. They ripped vegetation, and swallowed it whole. Their defining feature was their armor. They body was covered in thick, heavy bony plates, and most of the plates were fused together to make them even stronger. Embedded in the skin were more knobs of bone, and the outer skin above these knobs covered in keratin (the same stuff fingernails are made of). Ankylosaurus had a tail club, which consisted of several large osteoderms fused to the last few tail vertebrae. Ankylosaurus was discovered in 1908.

Figure 32: Right metatarsi of selected ornithopods in proximal view. A–R: (A) Diluvicursor pickeringi; (B) NMV P186047; (C) Morrosaurus antarcticus; (D) Gasparinisaura cincosaltensis; (E) Anabisetia saldiviai; (F) Kangnasaurus coetzeei; (G) Eousdryosaurus nanohallucis; (H) Dysalotosaurus lettowvorbecki; (I) Dryosaurus altus; (J) Changchunsaurus parvus; (K) Mantellisaurus atherfieldensis; (L) Hypsilophodon foxii; (M) Tenontosaurus tilletti; (N) Cumnoria prestwichii; (O) Muttaburrasaurus langdoni; (P) Talenkauen santacrucensis; (Q) Parksosaurus warreni; and (R) Thescelosaurus assiniboiensis. Metatarsi normalised for dorsoplantar depth of metatarsal II (shaded black). Dashed lines indicate uncertain bone margins. ?, indicates location of uncertain/expected/missing metatarsal. Abbreviation: mt #, metatarsal position. For data sources, see Table S1.

Close-up of the traumatic lesion observed in the right squamosal bone of Big John, a fossilized specimen of the dinosaur species Triceratops horridus. This image shows plaque-like deposition of reactive bone (white arrows) and lytic lesions (black arrows) on the surface around the lesion. These suggest that the lesion was surrounded by newly-formed bone and, therefore, had started to heal. This image was originally published as Figure 1c in the following journal article: Ruggero D’Anastasio, Jacopo Cilli, Flavio Bacchia, Federico Fanti, Giacomo Gobbo & Luigi Capasso (2022) Histological and chemical diagnosis of a combat lesion in Triceratops Scientific Reports, 12, 3941 (2022). DOI: 10.1038/s41598-022-08033-2 This article was published with the following license: "This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/." Figure 1c is published without a credit line and, therefore, falls under the article's CC BY 4.0 licence.

Mounted replica of a composite skeleton of Edmontosaurus annectens on display at the University of Oxford Museum, Oxford, England. The original skeleton is compiled from disarticulated fossil bones from a bonebed of the Hell Creek Formation, exposed in the Ruth Mason Quarry in Harding County, South Dakota. It is 8.5 m (28 ft.) long and the skull is almost 1 m (39 in.) in length.[1][2] ↑ Dinosaurs in the Museum. Oxford University Museum of Natural History (brochure, PDF), p. 7 ↑ BHI Fossil Replica Catalog 2012. Black Hills Institute of Geological Research, Inc., Hill City, SD, 2012 (PDF), p. 22

Mounted replica of a composite skeleton of Edmontosaurus annectens on display at the University of Oxford Museum, Oxford, England. The original skeleton is compiled from disarticulated fossil bones from a bonebed of the Hell Creek Formation, exposed in the Ruth Mason Quarry in Harding County, South Dakota. It is 8.5 m (28 ft.) long and the skull is almost 1 m (39 in.) in length.[1][2] ↑ Dinosaurs in the Museum. Oxford University Museum of Natural History (brochure, PDF), p. 7 ↑ BHI Fossil Replica Catalog 2012. Black Hills Institute of Geological Research, Inc., Hill City, SD, 2012 (PDF), p. 22