Fig 1.
Map of Cretaceous-aged dinosaur fossil localities of Mongolia.
Gobihadros mongoliensis was collected from Bayshin Tsav in Area C. Open squares indicate Late Cretaceous sites, solid squares represent Early Cretaceous localities. Abbreviations: A, Localities of Western Gobi Desert in Mongolia, mainly group of localities of Nemegtian age (early Maastrichtian), Late Cretaceous; B, Localities of Central Gobi Desert in Mongolia, mainly Djadokhtian age (Campanian), Late Cretaceous; C & D- Localities of Eastern Gobi Desert in Mongolia, mainly Baynshirenian age (Cenomanian-Santonian), Late Cretaceous. Figure has been modified from Tsogtbaatar et al. 2014, Figure 1 [24].
Fig 2.
Skull and mandible of Gobihadros mongoliensis.
Skull and mandible (MPC-D100/763) in left lateral (A), dorsal (B), ventral (C), and posterior (D) views. Abbreviations: an, angular; ar, articular; at, atlas; atr, atlantal rib; ax, axis; boc, basioccipital; bsp, basisphenoid; cop, coronoid process; c3, 3rd cervical vertebra; d, dentary; exo, exoccipital; f, frontal; gl, glenoid for the lateral quadrate condyle; hy, hyoid; j, jugal; l, lacrimal; mx, maxilla; n, nasal; p, parietal; pa, palpebral; pat, proatlas; pd, predentary; pf, prefrontal; pl, palatine; pm, premaxilla; po, postorbital; poc, paroccipital process; pt, pterygoid; q, quadrate; qj, quadratojugal; rap, retroarticular process; s, surangular; scl, sclerotic ring; soc, supraoccipital; sq, squamosal; v, vomer.
Fig 3.
Premaxilla of Gobihadros mongoliensis.
Premaxillae (MPC-D100/746, left and right) in dorsal (A) and ventral (B) views. Abbreviations: clp, caudolateral process; dp, dorsal process; en, external naris; for, premaxillary foramen; mg, maxillary groove; mr, midline recess for rostromedial process of the maxilla; ns, nasal suture; rm, rostral margin.
Fig 4.
Nasal (MPC-D100/746, left) of Gobihadros mongoliensis.
Nasal (MPC-D100/746, left) in dorsal (A), lateral (B), and ventral (C) views. Abbreviations: clpmx, suture for caudolateral process of the premaxilla; dpms, suture for dorsal process of the premaxilla; for, foramen; fs, frontal suture; nm, narial margin; pfs, prefrontal suture; pms, premaxillary suture.
Fig 5.
Maxilla of Gobihadros mongoliensis.
Maxilla (MPC-D100/746, right) in lateral (A) and medial (B) views. Abbreviations: af, alveolar foramina; ap, alveolar parapet; dp, dorsal process; ectsh, ectopterygoid shelf; js, jugal suture; ls, lacrimal suture; pms, premaxillary suture; rlp, rostrolateral process; rmp, rostromedial process.
Fig 6.
Jugal of Gobihadros mongoliensis.
Jugal (MPC-D100/746, right) in lateral (A), medial (B), and dorsal (C) views. Abbreviations: cdp, caudal process; fvf, free ventral flange; itf, infratemporal fenestra; lap, lacrimal process; ls, lacrimal suture; mxf, maxillary facet; mxp, maxillary process; orm, orbital margin; plf, palatine facet; pof, postorbital facet; pop, postorbital process; qjf, facet for the rostral process of the quadratojugal; rop, rostral process.
Fig 7.
Prefrontal and lacrimal of Gobihadros mongoliensis.
Prefrontal and lacrimal (MPC-D100/746, right) in lateral (A), posterior (B), and medial (C) views. Abbreviations: for, foramen; fs, frontal suture; js, jugal suture; l, lacrimal; lf, lacrimal foramen; ns, nasal suture; or, orbit; orm, orbital margin; paf, palpebral facet; pf, prefrontal; pmf, facet for caudolateral process of premaxilla.
Fig 8.
Braincase of Gobihadros mongoliensis.
Braincase (MPC-D100/746) in right lateral (A) and ventral (B) views. Abbreviations: apl, arteria palatinus; boc, basioccipital; bpt, basipterygoid; bptp, basipterygoid process; bsp, basisphenoid; bt, basal tubera; cc, carotid canal; exo, exoccipital; f, frontal; lsp, laterosphenoid; op, opisthotic; osp, orbitosphenoid; p, parietal; pfs, prefrontal suture; pos, postorbital suture; pr, prootic; prs, presphenoid; ps, parasphenoid; sq, squamosal; I-XII, foramina for cranial nerves.
Fig 9.
Postorbital of Gobihadros mongoliensis.
Postorbital (MPC-D100/746, right) in lateral (A), medial (B), ventral (C), and dorsal (D) views. Abbreviations: fs, frontal suture; itfm, infratemporal fenestra margin; jp, jugal process; or, orbit; orm, orbital margin; sqp, squamosal process; sqs, squamosal suture.
Fig 10.
Quadrate of Gobihadros mongoliensis.
Quadrate (MPC-D100/746, left) in lateral (A) and posterior (B) views. Abbreviations: arc, articular condyle; bu, buttress beneath head of quadrate; dqjf, dorsal quadratojugal facet; ptw, pterygoid wing; qh, quadrate head; qjn, quadratojugal notch; sac, surangular condyle; vqjf, ventral quadratojugal facet.
Fig 11.
Quadratojugal of Gobihadros mongoliensis.
Quadratojugal (MPC-D100/746, right) in medial (A) and lateral (B) views. Abbreviations: jf, jugal facet; qs, quadrate suture.
Fig 12.
Palatine of Gobihadros mongoliensis.
Palatine (MPC-D100/746, left) in lateral (A), medial (B), dorsal (C), and ventral (D) views. Abbreviations: js, jugal suture; mxs, maxillary suture; pts, pterygoid suture; rpt, rostral pterygoid; vs, vomer suture.
Fig 13.
Pterygoid of Gobihadros mongoliensis.
Pterygoid (MPC-D100/746, left) in lateral (A), medial (B), ventral (C), and dorsal (D) views. Abbreviations: bpta, basipterygoid articulation; dqp, dorsal quadrate process; mxs, maxillary suture; plr, palatine ramus; pls, palatine suture; vqp, ventral quadrate process.
Fig 14.
Predentary of Gobihadros mongoliensis.
Predentary (MPC-D100/746) in lateral (A), anterior (B), dorsal (C), and posterior (D) views. Abbreviations: cusp, denticulations on oral margin; dp, dorsal process; ig, internal groove; lp, lateral process; om, oral margin; pdf, predentary foramina, vp, ventral process.
Fig 15.
Mandible of Gobihadros mongoliensis.
Mandible (MPC-D100/746, right) in lateral (A) and medial (B) views. Abbreviations: afo, adductor fossa; alp, alveolar parapet; an, angular; ar, articular; cop, coronoid process; cos, coronoid portion of surangular; ds, dentary symphysis; gl, glenoid; lb, lateral buttress; mac, mandibular canal; nvf, neurovascular foramen; par, prearticular; pds, predentary suture; rap, retroarticular process; s, surangular; sp, splenial.
Fig 16.
Maxillary teeth of Gobihadros mongoliensis.
Maxillary teeth (MPC-D100/746) in buccal (A), lingual (B), and occlusal (C) views. Interpretative drawing in buccal (D), lingual (E), and occlusal (F) views. Abbreviations: crp, crown of replacement tooth; dsh, distal shelf; msh, mesial shelf; os, occlusal surface; pr, primary ridge.
Fig 17.
Dentary tooth of Gobihadros mongoliensis.
Dentary tooth (MPC-D100/746, left) in lingual (A), mesial (B), and buccal (C) views. Interpretive drawing in lingual (D), mesial (E), and buccal (F) views. Abbreviations: dent, marginal denticles of crown; dsh, distal shelf; gr, grooves to accommodate the margins of crown of replacement tooth; msh, mesial shelf; os, occlusal surface; pr, primary ridge; rt, replacement roots; sr, secondary ridge.
Fig 18.
Cervical vertebrae (MPC-D100/746) of Gobihadros mongoliensis.
Atlas in cranial (A), dorsal (B), and left lateral (C) views. Cranial cervical vertebra (c5) in cranial (D), dorsal (E), and right lateral (F) views. Caudal cervical vertebra (c11) in cranial (G), dorsal (H), and right lateral (I) views. Abbreviations: cr, cervical rib; di, diapophysis; na, neural arch; nc, neural canal; nsp, neural spine; oca, occipital condyle articulation; poz, postzygapophysis; pp, parapophysis; prz, prezygapophysis.
Fig 19.
Dorsal vertebrae and ribs (MPC-D100/746) of Gobihadros mongoliensis.
Cranial dorsal vertebra (D1) in cranial (A), dorsal (B), and right lateral (C) views. Cranial-to-middle dorsal vertebra (D7) in cranial (D), dorsal (E), and right lateral (F) views. Middle-to-caudal dorsal vertebra (D15) in cranial (G), dorsal (H), and right lateral (I) views. Abbreviations: di, diapophysis; nc, neural canal; nsp, neural spine; pp, parapophysis; poz, postzygapophysis; prz, prezygapophysis; tp, transverse process.
Fig 20.
Sacral block with ilia of Gobihadros mongoliensis.
Sacral block with ilia (MPC-D100/746) in left lateral (A), ventral (B), and dorsal (C) views. Abbreviations: ac, acetabulum; isp, ischial peduncle; nsp, neural spine; bs, brevis shelf (postacetabular notch); poap, postacetabular process; prn, preacetabular notch; prp, preacetabular process; pup, pubic peduncle; sap, supraacetabular process; sdv, sacrodorsal vertebra; sr, sacral ribs; s1—s6, first through sixth sacral vertebrae.
Fig 21.
Caudal vertebrae and chevrons (MPC-D100/746) of Gobihadros mongoliensis.
Proximal caudal vertebra (Cd2) in left lateral (A), proximal (B), and dorsal (C) views. Proximal-to-middle caudal vertebra (Cd13) in left lateral (D), proximal (E), and dorsal (F) views. Middle caudal vertebra (Cd28) in left lateral (G), proximal (H), and dorsal (I) views. Middle-to-distal caudal vertebra (Cd40) in left lateral (M), proximal (N), and dorsal (O) views. Distal caudal vertezbra (Cd55) in left lateral (M), proximal (N), and dorsal (O) views. Chevrons (ch5, ch14, ch26 and ch30) in right lateral and proximal (P) views. Abbreviations: cdr, caudal rib; haf, haemal arch (chevron) facet; nc, neural canal; nsp, neural spine; poz, postzygapophysis; prz, prezygapophysis.
Fig 22.
Scapula and coracoid of Gobihadros mongoliensis.
Scapula and coracoid (MPC-D100/746, left) in lateral (A), medial (B), ventral (C), and dorsal (D) views. Abbreviations: acp, acromion process; cf, coracoid foramen; cg, coracoid glenoid; df, deltoid fossa; dr, deltoid ridge; sb, scapular blade; sg, scapular glenoid; vps, ventral protuberance of the scapula.
Fig 23.
Sternal plate of Gobihadros mongoliensis.
Sternal (MPC-D100/746) in ventral (A) and dorsal (B) views. Abbreviations: cca, costal cartilage attachment; sca, sternal cartilage attachment.
Fig 24.
Humerus of Gobihadros mongoliensis.
Humerus (MPC-D100/746, right) in posterior (A), anterior (B), lateral (C), and medial (D) views. Abbreviations: dpc, deltopectoral crest; hh, humeral head; lt, lateral tuberosity; ms, muscle scar; mt, medial tuberosity; of, olecranon fossa; rc, radial condyle; uc, ulnar condyle.
Fig 25.
Ulna and radius (MPC-D100/746, right) of Gobihadros mongoliensis.
Ulna in anterior (A) and lateral (B) views. Right radius in lateral (C) and medial (D) views. Abbreviations: lp, lateral process; mp, medial process; olp, olecranon process; rf, radial facet; rh, radial head; uf, ulnar facet.
Fig 26.
Manus of Gobihadros mongoliensis.
Manus (MPC-D100/746, right) in dorsal (A) and ventral (B) views. Manus (MPC-D100/763, right) in dorsal (C) and ventral (D) views. Abbreviations: im, intermedium; mc-II, metacarpal-II; mc-III, metacarpal-III; mc-IV, metacarpal-IV; mc-V, metacarpal-V; un, ulnare; ung-I, ungual of digit-I; ung-II, ungual of digit-II.
Fig 27.
Ischium of Gobihadros mongoliensis.
Ischium (MPC-D100/760, right) in medial (A) and lateral (B) views. Abbreviations: ac, acetabulum; ip, iliac peduncle; isf, ischial foot; iss, ischial shaft; obf, obturator foramen; obp, obturator process; pup, pubic peduncle.
Fig 28.
Pubis of Gobihadros mongoliensis.
Pubis (MPC-D100/746, right) in lateral (A) and medial (B) views. Abbreviations: ac, acetabulum; ip, iliac peduncle; isp, ischial peduncle; ppb, prepubic blade; pps, prepubic shaft; pu, pubis.
Fig 29.
Femur of Gobihadros mongoliensis.
Femur (MPC-D100/746, right) in lateral (A), medial (B), posterior (C), ventral (D), and dorsal (E) views. Abbreviations: ct, cranial trochanter; eg, extensor groove; et, extensor tunnel; fg, flexor groove; fh, femoral head; gif, groove for m. iliofibularis; gt, greater trochanter; lc, lateral condyle; mc, medial condyle; 4t, fourth trochanter.
Fig 30.
Tibia and fibula of Gobihadros mongoliensis.
Tibia and fibula (MPC-D100/746, right) in lateral (A), anterior (B), and posterior (C) views. Abbreviations: ast, astragalus; cal, calcaneum; cnc, cnemial crest; fb, fibula; lm, lateral malleolus; lc, lateral condyle; mc, medial condyle; mm, medial malleolus.
Fig 31.
Pes of Gobihadros mongoliensis.
Pes (MPC-D100/754, left) in dorsal (A) and ventral (B) views. Abbreviations: II-IV, second through forth digits; mt-II, second metatarsal; mt-III, third metatarsal; mt-IV, fourth metatarsal; pph, proximal phalanx; puph, penultimate phalanx; ung, ungual.
Fig 32.
Cladogram depicting the phylogenetic relationships of Gobihadros mongoliensis.
Strict Consensus Tree of 208 most parsimonious trees resulting from the phylogenetic analysis (see text for details), indicating the phylogenetic position of Gobihadros mongoliensis amoung hadrosauroids. Tree Length = 226 steps, consistency index = 0.59, retention index = 0.85.
Fig 33.
Skeletal reconstructions of Gobihadros mongoliensis.
Skull (MPC-D100/763) of Gobihadros mongoliensis in left lateral (A), anterior (B), dorsal (C), and posterior (D) views. Schematic reconstruction of the skeleton of Gobihadros mongoliensis (E) in lateral view. Abbreviations: an, angular; boc, basioccipital; bsp, basisphenoid; d, dentary; exo, exoccipital; f, frontal; fm, foramen magnum; hy, hyoid; j, jugal; l, lacrimal; mx, maxilla; n, nasal; p, parietal; pa, palpebral; pd, predentary; pf, prefrontal; pm, premaxilla; po, postorbital; pt, pterygoid; q, quadrate; qj, quadratojugal; s, surangular; soc, supraoccipital; sq, squamosal.
Fig 34.
Schematic depicting the limb proportions of Gobihadros mongoliensis relative to other iguanodontians.
The forelimbs of several iguanodontians on the left scaled to a generalized hindlimb on the right, following [44], to show differences in limb proportions. The phalangeal formula of the manus occurs below each forelimb of the corresponding taxon. Modified from Figure 81 of [44].