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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.

Reconstructed skeleton of a megaraptoran highlighting the known bones of Joaquinraptor casali in blue. Reconstruction by TK Robinson and Andrew McAfee. Scale bar=1 m.

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.

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.

Skeletal composite of the chilean titanosaur Atacamatitan chilensis. A fragmented sauropod known from the holotype SGO-PV-961, found in the Atacama Desert. The preserved elements consist of:[1] Right femur, the proximal end of a humerus, two dorsal vertebrae, posterior caudal vertebrae, dorsal ribs and a possibly fragmentary element of the sternum, other fragmented caudal vertebrae and indeterminate bones.[1] Due to the fragmented nature of the holotype, most cladistic analyzes exclude Atacamatitan. Nevertheless, in 2012, Rubilar-Rogers and Gutstein conducted a preliminary cladistic analysis which placed Atacamatitan within the Lithostrotia.[2] The original description lacks a lateral view for the humerus and femur, the lateral view for the humerus was based on Alamosaurus and Opisthocoelicaudia, since it shows resemblance with them. The lateral view of the femur is based on Mendozasaurus for the same reason. Color Key   Known   Unknown

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.

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.

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.

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.

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.

Skeletal reconstruction of the Spectrovenator ragei holotype (MZSP-PV 833). Recovered bones in blue.

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.

A skull reconstruction and cranial bones from Shaochilong maortuensis, a small-bodied mid Cretaceous (Turonian) carcharodontosauri-an theropod from Inner Mongolia, China. A, skull reconstruction (courtesy of Brett Booth); B, right maxilla in lateral view (IVPP V.2885.4); C, braincase and skull roof in dorsal view (IVPP V.2885.1-2). Scale bars equal 5 centimeters.

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) Skeletal reconstruction in left lateral view (missing and damaged portions of the bones in gray). (B) Left ilium in lateral view. (C) Proximal caudal vertebrae in left lateral view with close-up of the infraprezygapophyses. (D) Chevron in cranial view. (E-F) Right scapula in dorsal (E) and lateral (F) views. (G) Last sacral and the two proximalmost caudals in left lateral view. (H) Right pubis in medial view. (I) Right ischium in lateral view. (J) Right femur in distal view. (K) Left metatarsus and distal tarsals in proximal view. (L) Right femur in cranial view. (M-N) Left metatarsus in lateral (M) and dorsal (N) views. Abbreviations: acr, acromion process; ant, antitrochanter; ch, chevron; cv, caudal vertebra(e); diprf, dorsal infraprezygapophyseal fossa; dt, distal tarsal(s); fct, cranial trochanter of femur; fh, femoral head; gl, glenoid fossa; idf, infradiapophyseal fossa; lc, lateral condyle; mc, medial condyle; mep, medial epicondyle; miprf, middle infraprezygapophyseal fossa; mt II, metatarsal II; mt IV, metatarsal IV; mt V, metatarsal V; ns, neural spine; obp, obturator process; pra, preacetabular process; pup, pubic peduncle; sprf, supraprezygapophyseal fossa; sv, sacral vertebra; tfc, tibiofibular crest; tp, transverse process; viprf, ventral infraprezygapophyseal fossa. Scale bars equal 10 cm in (A); 1 cm in (B-N). https://doi.org/10.1371/journal.pone.0210867.g004

Skeletal reconstruction of Dineobellator notohesperus gen. et sp. nov., SMP VP-2430, with known elements colored in white. Figured bones are as follows: fused distal caudal vertebra (A); middle caudal vertebra (B); caudal vertebra 1 (C); right femur (D); rib (E); right basipterygoid (F); left lacrimal (reversed) (G); right jugal (H); right humerus (I); right ulna (J); right metacarpal III (K); right manual ungual II (L); right metatarsal II (M); right metatarsal III. (N) Individual scale bars, 2 cm. Skeletal drawing based off work of Scott Hartman.