specimen

A 6.4 meter (21ft) Eurhinosaurus species specimen from the Holzmaden Formation, Baden-Wurttenburg, Germany. ~185 million years old.

"Daspletosaurus torosus" skeleton cast, reconstructed and mounted by Triebold Paleontology based on a nearly complete specimen from Montana's Judith River Formation

The holotype anterior dorsal vertebra of Uragasaurus kalasinensis (PRC 460) in anterior (a) and posterior (b) views. Digital rendering of the specimen in anterior (c), posterior (d), right lateral (e), left lateral (f), dorsal (g), and ventral (h) views. Asterisk refers to an autapomorphic character. The blue highlight indicates the pneumatic fossa and pleurocoel.

Neotype fossil of Ardeadactylus longicollum, specimen number SMNS 56603 (Number 58 in Wellnhofer 1970).

Comparison of cranial features between closely related southern Laramidian taxa; (A), Akainacephalus johnsoni (UMNH VP 20202) from the Late Cretaceous Kaiparowits Formation of Utah; and (B), Nodocephalosaurus kirtlandensis (SMP VP-900) from the Late Cretaceous Kirtland Formation of New Mexico, in left lateral views. Various synapomorphies are shared with N. kirtlandensis (highlighted in black and white arrows) and includes “flaring nostrils”; enlarged, laterally projecting, loreal osteoderms that are situated directly dorsal to the external nares. Other synapomorphies include pyramid-shaped nasal and frontal osteoderms positioned on the dorsal regions of the skull. A number of significant differences have been observed between both specimens; in A. johnsoni, the anterior, and posterior supraorbital bosses form an enlarged element that is somewhat backswept, whereas in N. kirtlandensis, the posterior and anterior supraorbital bosses are clearly defined as individual osteoderms, and are much smaller in size. Additionally, the squamosal horn in Akainacephalus is very small but is prominent and tetrahedrally shaped in Nodocephalosaurus. The quadratojugal horn in Akainacephalus is massive, has a subtriangular morphology in lateral view and projects almost entirely ventral, whereas in Nodocephalosaurus, the quadratojugal horn is smaller and has a typical fin-shaped morphology. Study sites: asob, anterior supraorbital boss; ext naris, external naris; laca, lacrimal caputegulum; loca, loreal caputegulum; naca, nasal caputegulae; orb, orbit; psob, posterior supraorbital boss; qjh, quadratojugal horn; sqh, squamosal horn.

Archaeopteryx lithographica, specimen displayed at the Museum für Naturkunde in Berlin. (This image shows the original fossil - not a cast.)

Mounted skeleton of Acrocanthosaurus specimen NCSM 14345 at North Carolina Museum of Natural Sciences

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.

Silesaurid left dentaries. (A) Kwanasaurus williamparkeri (based primarily on DMNH EPV.63136) in lateral view, (B) same in medial view, (C) Asilisaurus kongwe (NMT R89) in lateral view, (D) same in medial view, (E) Eucoelophysis baldwini (GR 224) in lateral view, (F) same in medial view, (G) Technosaurus smalli (TTU P-9021, reversed) in lateral view, (H) same in medial view (also reversed), (I) Sacisaurus agudoensis (composite based on MCN PV10042 and MCN PV10043) in lateral view, (J) same in medial view, (K) Silesaurus opolensis (ZPAL AbIII/361/26) in lateral view, (L) same in medial view, (M) Diodorus scytobrachion (MNHM-ARG 30) in lateral view (reversed), (N) same in medial view (also reversed), (O) Soumyasaurus aenigmaticus (TTU-P1125b) in lateral view, (P) same in medial view. Dashed lines indicate broken edges. Unshaded regions indicate the surface of the specimen is not exposed. All scale bars = 1 cm.

Hypothetical reconstruction of the skeleton of Amanasaurus nesbitti gen. et sp. nov. depicting (in orange) the preserved portions. (a) CAPPA/UFSM 0374 (holotype), a proximal portion of a right femur in anterior view. (b) CAPPA/UFSM 0375 (referred specimen), a distal portion of a left femur in anterior view. Figures were generated with GIMP 2.8 (https://www.gimp.org/). Cropped from original image and letters adjusted to match.

Holotype and referred specimen of Amanasaurus nesbitti gen. et sp. nov. from the Candelária Sequence (mid-to-late Carnian) of the Santa Maria Supersequence, southern Brazil. Holotype (CAPPA/UFSM 0374) in anterior (a), lateral (b), proximal (c), medial (d), and posterior (e) views. Referred specimen (CAPPA/UFSM 0375) in anterior (f), lateral (g), posterior (h), and distal (i) views. alt anterolateral tuber, amt anteromedial tuber, at anterior trochanter, cl cleft, ctfb crista tibiofibularis, dlt dorsolateral trochanter, dltp posterior portion of the dorsolateral trochanter, fo foramen, fot fossa trochanterica, gt greater trochanter, lc lateral condyle, lia linea intermuscularis cranialis, mc medial condyle, ms muscle scar, no notch, pg proximal groove, pof popliteal fossa, scs sub-circular scar. Figures were generated with GIMP 2.8 (https://www.gimp.org/).

Skeletal reconstruction of Heyuannia yanshini (previously Ajancingenia yanshini). Specimens as: blue: MPC-D 100/30 (holotype); green: MPC-D 100/31; red: MPC-D 100/32; tan: MPC-D 100/20 (holotype skull of Conchoraptor gracilis).

Life restoration of the large, Middle Triassic Nevadan ichthyosaur Cymbopsondylus petrinus. This illustration is primarily based on specimen UCMP 9950, with much of the tail restored following UCMP 9947. The size of the eye was reconstructed based on UCMP 9954 and UCMP 9913. The unknown distal portions of the flippers, as well as some of the tail, was reconstructed after the related genus Xinminosaurus. References Merriam, J. C. (1908) Triassic Ichthyosauria: With special reference to the American forms, Berkley, California: Berkley: The University Press Klein, N.; Schmitz, L.; Wintrich, T.; Sander, P. M. (2020). "A new cymbospondylid ichthyosaur (Ichthyosauria) from the Middle Triassic (Anisian) of the Augusta Mountains, Nevada, USA". Journal of Systematic Palaeontology 18 (14): 1167-1191. DOI:10.1080/14772019.2020.1748132. Jiang, D.; Motani, R.; Hao, W.; Schmitz, L.; Rieppel, O.; Sun, Y.; Sun, Z. (2008). "New primitive ichthyosaurian (Reptilia, Diapsida) from the Middle Triassic of Panxian, Guizhou, southwestern China and its position in the Triassic biotic recovery". Progress in Natural Science 18 (10): 1315. DOI:10.1016/j.pnsc.2008.01.039.

A Specimen of Parapuzosia daubreei (de Grossouvre, 1894), Santonian, Shumen on display at Sofia University "St. Kliment Ohridski' Museum of Paleontology and Historical Geology

Shetwemys, Plastral remains of the podocnemidid turtle S. fajumensis (Erymnochelyini). (a–b) NHMUK R3435, anterior plastral lobe, in ventral (a) and dorsal (b) views. (c–d) NHMUK R8441, plaster cast of the specimen CGM C8509, anterior plastral lobe, in ventral (c) and dorsal (d) views. (e–f) AMNH 5093, articulated epiplastra and entoplastron, in ventral (e) and dorsal (f) views. (g–h) SMNS 11233/6, anterior plastral lobe, in ventral (g) and dorsal (h) views. (i–j) NHMUK R3103, partial anterior plastral lobe, in ventral (i) and dorsal (j) views. (k–l) SMNS 11233/5, right hypoplastron, in ventral (k) and dorsal (l) views. (m–n) SMNS 11233/3, articulated left hypoplastron and xiphiplastron, in dorsal (m) and ventral (n) views, and detail of the outer ornamental pattern (o). Gebel Quatrani Formation, Fayum depression, Egypt, Lower Oligocene (Rupelian)

Close up of the Eulithomyrmex rugosus holotype head. Museum of Comparative Zoology specimen UCM17019. Priabonian; Florissant Formation, Colorado, USA