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Oneirosaurus caballeroi holotype IGMp879524. A, photograph, drawing and interpretative scheme of the specimen without left mandibular ramus, in right lateral view. B, photograph, drawing and interpretative scheme of the specimen without left mandibular ramus, in left lateral view. Gray fill, sediment; pattern fill, broken bone surface; black, empty space. Scale bars: A = 50 mm; C-D = 30 mm. Abbreviations: an, angular; avc, anterior aperture of the vidian canal; bo, basioccipital; bptm, basipterygoid meniscus; bs, basisphenoid; c, coronoid; d, dentary; ec, ectopterygoid; ep, epipterygoid; ex, exoccipital; f, frontal; im, internal auditory meatus; is, interorbital septum; j, jugal; la, lacrimal; m, mandible; mx, maxilla; na, nasal; op, opisthotic-exoccipital; p, parietal; par, prearticular; pl, palatine; pmx, premaxilla; pof, postorbitofrontal; pr, prootic; prf, prefrontal; ps, parasphenoid; pt, pterygoid; pvc, posterior aperture of the vidian canal q; quadrate; rv, right vomer; sa, surangular; scp, sclerotic plate; smx, septomaxilla; so, supraoccipital; sp, splenial; stp, stapes; VII, IX-XII, exit of cranial nerves.

Fossil bone of Procerosaurus exogyrarum, possible dinosaur from the Czech Republic. National Museum, Prague (2007).

Comparison of the holotype (BRSMG Cg3178, A and C right surangular, BAS specimen) and referred specimen (BRSMG Cg2488, B and D left surangular, Lilstock specimen) of Ichthyotitan severnensis gen. et sp. nov. To ease comparison, A and C have been reversed. A-B. Lateral view of both surangulars showing same unique shape; note the upturned, almost 90-degree angle bend and the spatulate-shaped posterior end. C-D. Medial view of both surangulars displaying same morphology posteriorly; anteriorly the Lilstock specimen (D) has been heavily eroded and distorted along its length. Note the position of an elongated foramen on the lateral surface (A-B), identified as part of the fossa surangularis that passes through the bone into the Meckelian canal. See also the damaged (?)angular that is articulated with the surangular and defined by a continuous groove (?suture) as seen in Fig 2H.

Partial skull and anterior cervical vertebrae of unidentified pliosaurid plesiosaurian (MPPL 18797) from the uppermost Callovian–middle Oxfordian of Kaberlaba (Asiago, Italy), in left lateral view. Photograph (A) and explanatory drawing (B). White, preserved bone surfaces; dark grey, preserved margins of skull fenestrae; light grey, eroded bone surface; cross hatching, broken bone.

Bone mapping of the skeleton of Plesiopharos moelensis gen. et sp. nov. (ML2302) from the Sinemurian (Lower Jurassic) of São Pedro de Moel (Leiria, Portugal). A. Bones distribution map of the three original extracted blocks (1, 2 and 3) containing ML2302. Arrows with question marks represent that the joining relationship between the blocks is unknown. B. Photographs of the five sub-blocks (1A, 1B, 2C, 2D, and 3E) after preparation works.

Outline and overview of the connected slabs TWE 480000454-A, -B, -D, -E, and -M. TWE 480000454-A shows a single plate-like girdle bone (is). TWE 480000454-B contains disarticulated vertebrae from the posterior presacral and sacral region (c1-11, na1-3), fragments of dorsal ribs (dr1, dr2), elements of gastral ribs (unlabelled), the second ischium (is), the round, plate-like pubis (pu), and three bones, most likely representing sacral- or caudal ribs (?cr1-3). TWE 480000454-D, -E, and -M mainly contain dorsal ribs (dr3-9) and elements of gastral ribs as well as two more isolated halves of neural arches (na4, na5), and a caudal rib (cr1).

A color-coded skull diagram of Palatodonta bleekeri, mostly based on a diagram published by Neenan et al. (2013). Some interpretations (such as the presence of a quadratojugal) are based on Maisch (2020). Depicted in left lateral view, mirrored from the original specimen as preserved in right lateral view. Dotted lines indicate missing bone.

Cuspicephalus scarfi MJMG K1918. A, Original skull on slab of mudstone, Lacking the mandible and dentition; B, outline diagram of preserved bone. Light grey is bone, dark grey is fibrous bone of sagittal crest, black is dental alveoli where unambiguous; C restoration of skull outline, with hypothetical lower jaw. Scale bar = 50 mm. Abbreviation: j, jugal; naof, nasoantorbital fenestra; m, maxilla; o, orbit; pm, premaxilla; q, quadrate; sc, sagittal crest; sq, squamosal; tr np, trace of nasal process.

Photographs of Melkamter pateko (MPEF-PV 11530), visible in medial views on the main block (1) with inset of the tooth (1B) and counterslab (2);. Rendered CT scan detail images (dashed areas represent visible bone that was too thin to be captured by CT scan) of the cranial fragment (1A), manual metacarpal (1C) and dorsal vertebrae (1D–F). Abbreviations: a = alveoli; if = infratemporal fenestra; j = jugal; l = lacrimal; m = maxilla; o = orbit; naof = Nnasoantorbital fenestra; np = nasal process; pm = premaxilla; po = postorbital; q = quadrate; qj = quadratojugal; s = squamosal; t = tooth; vas = vestigial ascending process.

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.

(A), silhouette of Maip macrothorax showing the preserved bones in white. (B), reconstruction of the thoracic cavity of Maip at level of D6. (C), interpretative drawing of the excavation of Maip showing the original disposition of the bones. Abbreviations: a, axis; c, coracoid; ind, indeterminate bone; g, gastralia; r, rib; v, vertebrae.

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.

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.

DMNH 2021-05-02, holotype left dentary of Ampelognathus coheni, photos and labeled outline drawings in A, lateral; B, medial; C, dorsal; D, ventral; E, anterior; and F, posterior views. Abbreviations: a#, alveolus and numerical position in tooth row; anf, angular facet; cof, coronoid facet; cop, coronoid process; d6, dentary tooth 6 base; ds, dentary symphysis; mc, Meckelian canal; mg, Meckelian groove; pdd, dorsal facet for predentary; pdv, ventral facet for predentary; saf, surangular facet. Gray fill indicates recessed surfaces. Stippling indicates visible sediment. Cross-hatching indicates broken bone surface. Scale bars equal 5 mm.

Skeletal reconstruction of Laquintasaura venezuelae, a prionodontian ornithischian (after Barrett et al., 2014). A predentary was restored on the mandible of Laquintasaura, but there is no proof that this bone was present.

Osteohistology of UALVP 59606, metatarsal IV of Citipes elegans. Overview of histological thin section of UALVP 59606 in plane-polarized (A) and cross-polarized (B) light, showing locations of close-up images. Detail (C) of cortex showing predominantly primary fibrolamellar bone with longitudinal-reticular vascularity, endosteal layer, and cyclical growth marks (arrows), under plane-polarized light. Close-up (D) of well developed endosteal layer on the medullary cavity, showing sec- ondary excavation by simple vascular canals, under cross-polarized light. Close-up (E) of tightly packed cyclical growth marks (arrows) near the periosteal surface of the cortex, under plane-polarized light. Close-up (F) of periosteal surface of cortex, showing avascular parallel-fibered bone indicating an incipient external fundamental system (double ended arrow) with three LAGs (arrows). Abbreviations: efs, incipient external fundamental system; el, endosteal lamellae; hb, Haversian bone; pfb, parallel-fibered bone; radv, radial simple vascular canal; so, secondary osteon.