formation

Sachicasaurus vitae - holotype - Paja Formation, Colombia

Holotype specimen (PIMUZ A/III 1274) of Prosantosaurus scheffoldi gen. et spec. nov. from the upper Prosanto Formation (Early Ladinian, Middle Triassic) of Ducanfurgga locality no. 4, southwest of Davos, Canton of Grisons, south-eastern Switzerland. A Nearly complete specimen as prepared in dorsal view. The posterior part of the tail was lost prior to burial. Both forearms are not visible but lie below the trunk region, pointing in an anteromedial direction (see Additional file 1: Fig. S3A). B Detail of skull and anterior neck region. C Outline sketch of skull sutures. D Detail of shoulder girdle (claviculae, scapulae) and anterior dorsal vertebrae and ribs. E Detail of right humerus. F Detail of posterior dorsal vertebrae and ribs, sacral vertebrae and ribs, and anterior caudal vertebrae and ribs. G Detail of left ilium and hindlimb. ar articular; as astragalus; bo basioccipital; cal calcaneus; cl clavicula; co coracoid; d dentary; en external naris; eo exoccipital; fe femur; fi fibula; fr frontal; hu humerus; il ilium; in internal naris; is ischium; j jugal; mx maxilla; na naris; o orbit; pa parietal; pl palatine; pmx premaxilla; pof postfrontal; po postorbital; prf prefrontal; pt pterygoid; pu pubis; q quadrate; qj quadratojugal; ti tibia; sacr sacral rib; sc scapula; so supraoccipital; sp splenial; sq squamosal; su surangular; utf upper temporal fenestra; v vomer

Mandible in Bagaraatan ostromi gen. et sp. n. from the mid-Maastrichtian Nemegt Formation at Nemegt, Mongolia. A-B. Reconstruction on left mandible in lateral and medial views. Left dentary in dorsal view. D-E. Posterior part of left mandible in dorsal and posterior views. F. Cross-section through dentary at the end of preserved fragment.

Reconstruction of the holotype material of Silutitan sinensis (IVPP V27874), a Cretaceous euhelopid sauropod from the Chinese Shengjinkou Formation, scaled after Euhelopus zdanskyi. Silhouette modified from "Euhelopus zdanskyi Skeletal" by Gunnar Bivens (CC BY 3.0) (https://www.deviantart.com/gunnarbivens/art/Euhelopus-zdanskyi-Skeletal-833724646)

Alvarezsauridae gen. et sp. indet., posterior caudal vertebrae. Dzharakuduk, Uzbekistan; Bissekty Formation, Upper Cretaceous (Turonian). a-e, ZIN PH 2441/16, two vertebrae preserved in articulation, in anterior (a), dorsal (b), posterior (c), lateral (d), and ventral (e) views. f-j, ZIN PH 2442/16, vertebra missing ventral part of the centrum, in dorsal (f), lateral (g), ventral (h), anterior (i), and posterior (j).

Figure 1: Reconstruction of the skull of Bellusaurus sui from the Middle-Late Jurassic Shishugou Formation of Xinjiang, China. This reconstruction is a composite based on isolated holotypic and referred material. (A) Right lateral view. (B) Dorsal view. Holotypic elements are indicated in blue and referred elements are in green.

Jeholopterus ningchengensus Wang, Zhou, Zhang, and Xu, 2002, IVPP V 12705, Lower Yixian Formation (Early Cretaceous), China.

Skeletal reconstruction of Ahshislepelta minor, a small ankylosaur from the Late Cretaceous Kirtland Formation of New Mexico. While originally recovered as an ankylosaurid related to Gastonia, later analyses favored a nodosaurid position which this is based on. Based on the holotype SMP VP-1930, consisting of fragmentary shoulder, forelimb, and vertebral elements as well as several osteoderms. Unknown material filled in using Niobrarasaurus, Pawpawsaurus, Silvisaurus, Sauropelta, and Borealopelta. Total length is approximately 4.9 m through the centra. Notes: Osteoderm placement somewhat speculative, not all osteoderms and vertebral fragments are figured. References: Burns & Sullivan, 2011.

This reconstruction of Marambionectes molinai, found from the Lopez de Bertodano Formation, is based off of other related elasmosaurs such as Aristonectes and Nakonanectes.

Braincase of WSC 10058, holotype of Ornatops Braincase of Ornatops incantatus in digital 3D model in right lateral (A and C) and left lateral (D and F) views, with enlarged images of the right (B) and left (E) auditory regions. Credit: McDonald AT, Wolfe DG, Freedman Fowler EA, Gates TA. 2021. A new brachylophosaurin (Dinosauria: Hadrosauridae) from the Upper Cretaceous Menefee Formation of New Mexico. PeerJ 9:e11084 https://doi.org/10.7717/peerj.11084

The hadrosaurid dinosaur Wulagasaurus dongi gen. et sp. nov. from the Upper Cretaceous Yuliangze Formation at the Wulaga quarry, China. A. Holotype GMH W184, right dentary in lateral (A1) and medial (A2) views. B. GMH W217, right dentary in lateral (B1) and medial (B2) views.

Tetanuran theropod Cruxicheiros newmanorum gen. et sp. nov. axial vertebrae (WARMS 15771) from the Chipping Norton Limestone Formation, Bathonian of the United Kingdom. A. Posterior cervical or anterior dorsal vertebra in posterior view. B. Partial middle−posterior dorsal vertebra in right lat− eral view showing a sagittal cross−section (B1) and in dorsal view (B2). C. Middle−distal caudal vertebra in left lateral (C1) and posterior (C2) views. D. Mid− dle−posterior dorsal neural arch in anterior (D1), right lateral (D2, D3), and posterior (D4) views. Photographs (A, B1, B2, C1, C2, D1, D2, D4) and line drawing (D3). Crossed−hatching indicates matrix and grey tone indicates broken bone.

Holotype of the polycotylid[1] plesiosaur Edgarosaurus muddi DRUCKENMILLER, 2002, (MOR 751) comprising the skull, the neck, and the left front flipper, on display in the Museum of the Rockies in Bozeman, Montana. The specimen was collected in Edgar, Carbon County, Montana, from the Shell Creek member of the Thermopolis Shale Formation, Upper Albian, uppermost Lower Cretaceous.[2]

Abelisaurid theropod Kryptops palaios gen. et sp. nov. MNN GAD1−1 from the Lower Cretaceous Elrhaz Formation of Niger. Left maxilla in lateral view; stereopair (A) and line drawing (B). Cross−hatching indicates broken bone; dashed lines indicate estimated edges.

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.

Left ilium of the camarasauromorph sauropod Brontomerus mcintoshi from the Lower Cretaceous Cedar Mountain Formation of Utah, type specimen OMNH 66430 in lateral view reconstructed from the three fragments (A), and ventral view (B).