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Reconstruction of the Bravoceratops skeleton with known bones marked in white. Specimen: TMM 46015-1 (holotype). Scale bar=2 m. Total length along centra=6.97 m.

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.

Holotype of Jakapil kaniukura (MPCA-PV-630), postcranial bones. Speculative silhouette showing preserved elements (a); osteoderm distribution is speculative and partial to show non-osteodermal elements); dorsal vertebra elements in dorsal (b), right lateral (c) and anterior (d,e) views; sacral vertebra in left lateral view (f); mid-caudal vertebra in left lateral view (g); fragment of the mid-shaft of a dorsal rib in posterior view (the enlarged, broken posterior edge is highlighted (h); expanded distal ends of two dorsal ribs (i); left scapula in lateral view (j); right scapula in lateral view (k); right coracoid in lateral view (l); left and right humeri in anterior view (m); probable right ulna in lateral view (n); metacarpals, non-ungual and ungual phalanx in dorsal views (o); left femur elements in anterior view (p); proximal end of the right fibula in lateral view (q); distal end of the left tibia in anterior view (r); ischial elements in side view (s); cervical osteoderms in dorsal view (t), flat scutes in dorsal view (u), spine-like osteoderm in side view (v) and ossicle in dorsal view (w). ac acromial crest, aco asymmetrical cervical osteoderm, alp anterolateral process, ap acromial process, at anterior trochanter, bb basal bone, ebr expanded broken rib edge, di diapophysis, dpc deltopectoral crest, ft fourth trochanter, gl glenoid, mc metacarpals, nc neural canal, ncs neurocentral suture, ph non-ungual phalanx, pp pubic peduncle, poz postzygapophyses, rug marginal rugosities, sb scapular blade, sc scute, tp transverse process, uph ungual phalanx.

Skull in dorsal (a and b, photograph and drawing respectively), and left lateral (c and d, photograph and drawing respectively) views. (e) Premaxillary tooth; (f,g) maxillary teeth (g inverted). amf, anterior maxillary fossa; aof, antorbital fossa; aso, anterior supraorbital; d, dentary; ef, elliptical fossa; f, foramina; fr, frontal; ift, infratemporal fenestra; j, jugal; mx, maxilla; n, nasals; o, orbit; pd, predentary; pdb, postdentary bones; pmx, premaxilla; po, postorbital; pso: posterior supraorbital; prf, prefrontal; qj, quadratojugal; sq, squamosal; stf, supratemporal fenestra. 1–7 denticles. The drawings were processed using Adobe Photoshop CS2 Serial Number: 1045-1412-5685-1654-6343-1431.

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.

Preserved bones of Sanjuansaurus gordilloi (PVSJ 605), positioned as they were found in the field. Abbreviations: ca1–15, caudal vertebrae 1–15; c2–9, cervical vertebrae 2–9; d1–14, dorsal vertebrae 1–14; l Fe, left femur; l il, left ilium; l MII, left metatarsal II; l Sc, left scapula and coracoid; l Ti, left tibia; l Ul, left ulna; Ph, manual phalanx; R, rib; r As-Ca, right astragalus and calcaneum; r Fe, right femur; r Fi, right fibula; r Fe, right femur; r Mx, right maxilla; r Pu, right pubis; r Sc, right scapula and coracoid; r Ti, right tibia; s1–3, sacral vertebrae 1–3. Scale bars equals 20 cm.

Representative bones of Pulanesaura eocollum. (a) anterior-to-middle cervical vertebrae (BP/1/6199) in left lateral view; (b) holotypic anterior-most dorsal neural arch (BP/1/6882) in left lateral and anterior views; (c) anterior dorsal neural arch (BP/1/6984) in anterior and right lateral views; (d) anterior mid-dorsal neural arch (BP/1/6183) in anterior and right lateral views; (e) middle dorsal neural arch (BP/1/6770) in posterior view; (f) anterior caudal vertebra (BP/1/6646) in right lateral and posterior views; (g) right humerus (BP/1/6193) in anterior view; (h) left ulna (BP/1/6210) in lateral and proximal views; (i) ?left clavicle (BP/1/6752) in dorsal view; (j) left pedal ungual I (BP/1/6186) in proximal and medial views; (k) left tibia (BP/1/6200) in anterior and lateral views; (l) right ischium (reversed) (BP/1/7366) in lateral view. Abbreviations: aidf, anterior infradiapophyseal fossa; ain, anterior incline of the neural spine; ep, epipophysis; hyp, hyposphene; mr, medial ridge; pp, parapophysis; prdl, prezygodiapophyseal lamina; prz, prezygapophyses; rf, radial fossa; spol, spinopostzygapophyseal lamina; vc, ventral convexity. Scale bars equal 5 cm in a-f and i, j; 10 cm in g, h, k, l. Silhouette drawn by BWM Photographs by BWM.

Fig. 5. Forelimb bones of the titanosaurian sauropod Bustingorrytitan shiva gen. et sp. nov. from “Bustingorry II” site, Neuquén Province, Argentina, upper Cenomanian. A. Left coracoid (holotype, MMCH-Pv 59/13) in lateral view. B. Left scapula (holotype, MMCH-Pv 59/11) in lateral view. C. Left humerus (holotype, MMCH-Pv 59/21) in proximal (C1), anterior (C2), and distal (C3) views. D. Right radius (holotype, MMCH-Pv 59/22) in posterior view. E. Left sternal plate (holotype, MMCH-Pv 59/15) in dorsal view. F. Articulated metacarpals I–V (holotype, MMCH-Pv 59/25–29) in proximal (F1), anterior (F2) and distal (F3) views. G. Right ulna (holotype, MMCH-Pv 59/23) in medial (G1) and proximal (G2) views. Abbreviations: cf, coracoid foramen; gas, glenoid articular surface; igl, infraglenoid lip; I–V, metacarpals. Scale bars 200 mm.

Bones referred to Ibirania parva, A. Middle caudal vertebra (MPMA 08-0060-07) referred to I. parva. B. Views of partial right ulna (LPP-PV-0202) of the I. parva holotype. According to Navarro et al. (2022).

Herbivorous dinosaur found in the Al-khoudh area. This dinosaur is similar to the Zalmoxes and Rhabdodon dinosaurs. The skeleton in the Bait Al Baranda Museum was assembled from bones borrowed from several museums.

Dinosaur Bones

MRF 319, a partial oviraptorosaurian skeleton referred to Anzu wyliei. (A) Skeletal reconstruction in left lateral view, with preserved bones in gray and bones represented in other Anzu specimens in white (hatching indicates heavily reconstructed portions of the ilia of CM 78001). Middle-posterior (ninth?) cervical vertebra in (B) anterior, (C) left lateral, and (D) dorsal views. Posterior (11th?) cervical vertebra in (E) anterior, (F) left lateral, and (G) dorsal views. Posterior (12th?) cervical vertebra in (H) anterior, (I) left lateral, and (J) dorsal views. Anteroposteriorly crushed left radius in lateral (K) and anterior (L) views. Mediolaterally crushed left ulna in lateral (M) and anterior (N) views. (O) Partial left scapulocoracoid in lateral view. Dorsal rib in anterior (P) and posterior (Q) views. Abbreviations: acr, acromial process; cr, cervical rib; dip, distal processes; pat, pathology; pf, pneumatic fossa. Scale bars = 50 cm in A; 1 cm in B–Q.

MRF 319, a partial oviraptorosaurian skeleton referred to Anzu wyliei. Skeletal reconstruction in left lateral view, with preserved bones in gray and bones represented in other Anzu specimens in white (hatching indicates heavily reconstructed portions of the ilia. Scale bar = 50 cm (19.7 in)

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.