crâne

Skull of Dromiceiomimus

Skull of Saichania, Warsaw Museum of Evolution

Skull of Oohkotokia horneri, gen. et sp. nov. (MOR 433, holotype)

The incomplete skull and vertebrae of the holotype of Omphalosaurus nevadanus, seen in dorsal (left) and ventral view (right). This image was derived by combining plates 8 and 9 of Merriam (1906), done by an uncredited artist. Legend: A - angular D - dentary Pl - palatine Pt - pterygoid Sa - surangular Sp - splenial V - vertebrae a, b, c - "doubtful elements"

Restored Placochelys placodonta skull at the Museum für Naturkunde, Berlin.

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.

Riojasaurus skull cast, Copenhagen.

Skull of Pistosaurus longaevus (cast - USNM 16107) in right, left and posterior views.

Skull of Pistosaurus longaevus (cast - USNM 16107) in right, left and posterior views.

Skull replica of Vagaceratops at Canadian Museum of Nature

Skull cast of Anchiceratops ornatus (original specimen: TMP 1983.001.0001) on display at the University of Michigan Museum of Natural History.

Cranial remains of Arthropterygius chrisorum CCMGE 17–44/13328 (A–J) and PMO 222.669 (L, M). (A, B) Right postfrontal in ventral (A) and dorsal (B) views. (C) Left lateral view on articulated postfrontal, prefrontal and nasal. (D) Left prefrontal in ventral view. (E, F) Right prefrontal in ventral (E) and dorsal (F) views. (G, H) left nasal in dorsal (G) and ventral (H) views. (I, J) Left jugal in medial (I) and lateral (J) views. (K) Cranial reconstruction, showing the depicted elements (colored). (L, M) oblique dorsal view and interpretation of sutures of the skull roof of PMO 222.669. Abbreviations: ffr, facet for the frontal; fnas, facet of the nasal; fpo, facet for the postorbital; fpref, facet for the prefrontal; fqj, facet for the quadratojugal; fsut, facet for the supratemporal; lw, lateral wing of the nasal lamella; nas, nasal; par, parietal; pf, parietal foramen; pref, prefrontal; sut, supratemporal. Both scale bars represent 10 cm.

Skull of Lesothosaurus - ornithischian dinosaur

Skull of Lesothosaurus - ornithischian dinosaur

The nodosaurid dinosaur, Glyptodontopelta is mostly known from isolated osteoderms ("armor plates"). The specimen SMP VP-1580 (State Museum of Pennysylvania) is however, the most complete known specimen, comprising parts of the skull, hundreds of osteoderms and fragments. This specimen was discovered in 2003 by Warwick Fowler, in the Naashoibito Member of the Ojo Alamo Formation (Maatrichtian, Late Cretaceous) of the San Juan Basin, New Mexico, during an expedition led by Dr. Robert Sullivan.

Reconstruction and restoration of the skull of Eolambia. (A) Skull reconstruction of Eolambia in left lateral view by the lead author. Bones in white are unknown, bones in dark grey are based primarily upon the adult holotype (CEUM 9758) or paratype (CEUM 5212), and bones in light grey are based primarily upon juvenile elements from the Eo2 and WS8 bonebeds. Sutures and points of contact between bones are marked in black. Scale bar equals 10 cm; scale is calibrated with the dentary of CEUM 9758. (B) Life restoration of the head of Eolambia by Lukas Panzarin. Abbreviations: an, angular; d, dentary; f, frontal; j, jugal; l, lacrimal; mx, maxilla; na, nasal; pd, predentary; pmx, premaxilla; po, postorbital; prf, prefrontal; q, quadrate; qj, quadratojugal; sa, surangular; sq, squamosal.