skull

Reconstruction of the skull of Spinops sternbergorum gen. et sp. nov. from the Campanian of Dinosaur Provincial Park, southern Alberta, in right lateral view. Preserved elements are stippled; missing portions are dotted and modeled after Centrosaurus apertus.

Photograph of the holotype skull of Titanoceratops ouranos, from the late Campanian aged Kirtland/Fruitland beds of New Mexico, USA. Photograph by Nick Longrich

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.

Hualianceratops holotype IVVP V18641, Skull reconstruction

Figure 1: Holotype and skeletal reconstruction of Mosaiceratops azumai, gen. et sp. nov (ZMNH M8856). (a) photograph and line drawing of ZMNH M8856; (b) skeletal reconstruction showing preserved elements in white. Scale bar 10 cm. Abbreviations: a, astragalus; boc, basioccipital; c, calcaneum; cav, caudal vertebra; ch, chevron; cv, cervical vertebra; dr, dorsal rib; dv, dorsal vertebra; f, frontal; fem, femur; fl, fibula; h, humerus; il, ilium; is, ischium; L, left; mt, metatarsal; ph, phalanx/phalanges; po, postorbital; R, right; sk, skull; sq, squamosal; t, tibia; td, tendon; ?, undiagnostic remains.

Skeletal diagram featuring the optimal remains of the holotype of Graciliceratops mongoliensis: ZPAL MgD-I/156.[1] Found in the Bayan Shireh Formation, in the original description the remains were referred to the genus Microceratops (now obsolete).[2] However, Sereno in 2000 noted that there was no base for this referral, then, he created a new genus and species for this specimen.[1] The holotype is very fragmented (specially the skull), consisting of:[2] Fragmented skull; 4 cervical, 12 dorsal and 7 sacral vertebrae; right scapula; proximal end of left scapula; left coracoid; right humerus, radius and fragmentary ulna; proximal and distal end of left humerus; proximal fragments of both pubis; fragments of both illium and fragment of right ischium; right femur, tibia and nearly complete pes; distal part of left tibia, fragmentary left pes; tarsals and isolated ribs.[2] The sacral vertebrae are not fused, an indicator of the immaturity of this specimen; the estimated adult size is about 2 meters long or similar to Protoceratops.[2][1] Right quadratojugal, quadrate and fragmentary jugal were reversed in order to get an optimal view.

Holotype skull of Wannanosaurus yansiensis on display at the Paleozoological Museum of China.

Diagram featuring the holotype skull (ZPAL MgD-I/105) of Tylocephale gilmorei in left lateral view. Scale bar equals 5 cm (50 mm). Based on Maryańska & Osmólska, 1974,[1] and Sullivan, 2006.[2] References ↑ (1974). "Pachycephalosauria, a new suborder of ornithischian dinosaurs". Palaeontologica Polonica (30): 45−102. ↑ (2006). "A taxonomic review of the Pachycephalosauridae (Dinosauria: Ornithischia)". New Mexico Museum of Natural History and Science Bulletin (35): 347–365.

Lateral diagram of the skull of Sinocephale bexelli (Bohlin, 1953) with unknown regions (grey) restored after Stegoceras

Holotype of Transylvanosaurus platycephalus, LPB (FGGUB) R.2070, a partial skull comprising the articulated basicranium and both frontals. Scale bar: 1 cm.

skull of iguanodontian Altirhinus kurzanovi

Figure 4: Anterior portion of the skull of Dakotadon lakotaensis (SDSM 8656). (A) photograph in left lateral view; (B) photograph in right lateral view; (C) photograph in ventral view. Abbreviations: ant, anterior; post, posterior; vent, ventral. Scale bars equal 5.0 cm.

Angulomastacator skull reconstruction with known elements in white. Scale bar 20 cm.

Reconstruction of the skull of Tlatolophus galorum by sculptor Samuel Nieves Tlapaya (El Alebrije Prehistórico). Displayed in the lobby of the hosting hotel of the 12th Latin American Congress of Paleontology, held in Puebla, Mexico, during the first week of March 2025.

Minqaria bata skull reconstruction with known elements shown in white.

D. Dentary tooth crowns of Arenysaurus ardevoli (MPZ 2008/258) in lingual view. E. Caudal region of the skull roof of A. ardevoli (MPZ 2008/1) in dorsal view. F. Left dentary of A. ardevoli (MPZ 2008/258) in medial view.