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Various fossils pertaining to the holotype of the Triassic ichthyosaur Toretocnemus (originally Leptocheirus, also Merriamia) zitteli. This image is derived from plate 23 in Merriam (1903), done by an uncredited artist. The arrangement of the individual figures has been modified from the original (most notably, figures 3 and 4 were swapped to minimize confusion). Original description: Leptocheirus zitteli n. gen. and sp. Figures reproduced natural size from the type specimen. Fig. 1.— Right side of skull. Fig. 2. — Cross-section of posterior portion of the lower jaw, taken above the point marked A on the lateral view of the skull. Fig. 3. — Cross-section of the upper and lower jaws, taken at the break immediately behind the point marked Sp on the lateral view of the skull. Fig. 4. — Lateral view of an anterior caudal centrum. Legend (modified from original): Ar - articular A - angular D - dentary J - jugal L - lacrimal Mx - maxilla Po - postorbital Sa - surangular Se - sclerotic ring Sp - spenial T - cross-section of tooth X - doubtful element

The shoulder girdle of the holotype of the Triassic ichthyosaur Toretocnemus (originally Leptocheirus, also Merriamia) zitteli. This image is derived from plate 21 in Merriam (1903), done by an uncredited artist. The arrangement of the individual figures has been slightly modified from the original. Original description: Leptocheirus zitteli n. gen. and sp. Figures reproduced natural size from the type specimen. Fig. 1.—Clavicles (cl) and probable interelavicle (Ic and Ic')- The interclavicle has been separated into two fragments by a crack in the matrix. Fig. 2.—Inner side of the coracoids and the left scapula.

Forelimb and partial hindlimb of the holotype of the Triassic ichthyosaur Toretocnemus (originally Leptocheirus, also Merriamia) zitteli. This image is derived from plate 22 in Merriam (1903), done by an uncredited artist. Original description: Leptocheirus zitteli n. gen. and sp. Figures reproduced natural size from the type specimen. Fig. 1. — Superior side of left anterior limb. r, radius. Fig. 2. — Posterior limb. t, tibia.

Figure description from paper: "Figure 23: Early and Middle Triassic ichthyopterygian heads possessing longirostry. Simplified outlines of four different Early and Middle Triassic ichthyopterygian heads possessing a long and slender rostrum. Specimens are at the same scale. (A) Utatsusaurus hataii (UHR 30691, Motani, Minoura & Ando, 1998); (B) Grippia longirostris (PMU R445, Motani, 2000); (C) Mixosaurus cornalianus (BES SC 1000, Renesto et al., 2020); (D) Besanosaurus leptorhynchus (PIMUZ T 4847, this paper); (E) Cymbospondylus buchseri (PIMUZ T 4351, Sander, 1989). Scale bar represents 10 cm." References: Bindellini, G.; Wolniewicz, A.S.; Miedema, F.; Scheyer, T.M.; Dal Sasso, C. (2021). "Cranial anatomy of Besanosaurus leptorhynchus Dal Sasso & Pinna, 1996 (Reptilia: Ichthyosauria) from the Middle Triassic Besano Formation of Monte San Giorgio, Italy/Switzerland: Taxonomic and palaeobiological implications". PeerJ 9: e11179. DOI:10.7717/peerj.11179.

Figure description from paper: "Fig. 3 Wimanius odontopalatus Maisch & Matzke, 1998, holotype, GPIT-PV-76272. Photos courtesy of G. Bindellini (Milano). a The complete holotype. b Detail showing a part of the dentition. c Disarticulated bones from the posterior part of the skull

Figure description from paper: "Fig. 3 Wimanius odontopalatus Maisch & Matzke, 1998, holotype, GPIT-PV-76272. Photos courtesy of G. Bindellini (Milano). a The complete holotype. b Detail showing a part of the dentition. c Disarticulated bones from the posterior part of the skull

Becklespinax altispinax holotype BMNH R1828 (originally assigned to Megalosaurus bucklandii). Owen's description follows: Three anterior dorsal vertebræ : p, parapophysis, or lower transverse process: t, accessory tubercle contributing some attachment to the head of the rib : d, diapophyses, or upper transverse process, fractured, which gave attachment to the tubercle of the rib: b, oblique buttress extending from the parapophysis to the diapophysis, and contributing to the support of the neural platform : z, the prozygapophysis, z', the zygapophysis, forming the ends of the neural platform and articulating the neural arches of the vertebræ with each other, ns, the neural spine of the foremost of these vertebras, ns', the neural spine of the second vertebra; it expands at its extremity, overhangs the anterior shorter spine, and developes a strong bony plate from its back part which fixes it to n", the similarly developed and modified spine of the third vertebra. The extraordinary size and strength of the spines of these anterior dorsal vertebræ, indicate the great force with which the head and jaws of the Megalosaurus must have been used. From the Wealden, near Battle. In the Museum of Samuel H. Beckles, Esq., F.G.S.

Becklespinax altispinax holotype BMNH R1828 (originally assigned to Megalosaurus bucklandii). Owen's description follows: Three anterior dorsal vertebræ : p, parapophysis, or lower transverse process: t, accessory tubercle contributing some attachment to the head of the rib : d, diapophyses, or upper transverse process, fractured, which gave attachment to the tubercle of the rib: b, oblique buttress extending from the parapophysis to the diapophysis, and contributing to the support of the neural platform : z, the prozygapophysis, z', the zygapophysis, forming the ends of the neural platform and articulating the neural arches of the vertebræ with each other, ns, the neural spine of the foremost of these vertebras, ns', the neural spine of the second vertebra; it expands at its extremity, overhangs the anterior shorter spine, and developes a strong bony plate from its back part which fixes it to n", the similarly developed and modified spine of the third vertebra. The extraordinary size and strength of the spines of these anterior dorsal vertebræ, indicate the great force with which the head and jaws of the Megalosaurus must have been used. From the Wealden, near Battle. In the Museum of Samuel H. Beckles, Esq., F.G.S.

Ahvaytum bahndooiveche size comparison based on the data shown on Lovelace et al., 2025. Yellow dot size & weight its estimated using Mbiresaurus raathi (Griffin et al., 2022) as reference. Green dot size & weight its estimated using Saturnalia tupiniquim (Langer et al., 1999) as reference. Size estimation might change with more new material description in posterior studies.

Drawings of Dryolestida left upper−molar, modified from the original descriptions. A–C, Kimmeridgian; D–F, Tithonian–Berriasian; G–H, early Barremian; I, late Barremian. A. Left M4 or M5 of Comotherium richi Prothero, 1981, from the Upper Jurassic Morrison Formation, Como Bluff locality, Wyoming, USA. B. Right M5, reversed, of Dryolestes leiriensis Martin, 1999, from Guimarota, Portugal.C. Left M6 of Krebsotherium lusitanicum Martin, 1999, from Guimarota, Portugal. D. Right M4 or M 6 (reversed) of Portopinheirodon asymmetricus Martin, 1999, Porto Pinheiro, Lourinha, Portugal. E. Right M5 (reversed) of Laolestes andresi Martin, 1999, from Porto Pinheiro, Lourinha, Portugal. F. Right upper molar of Donodon perscriptoris Sigogneau−Russell, 1991, Anoual, Morocco.G. Left M4 orM5 of Crusafontia amoae sp. nov., holotype, Cuesta Corrales 2, El Castellar Formation, Galve, Teruel, Spain. H. Right M6 orM7 (reversed) of Crusafontia amoae sp. nov., first described as upper molar of Crusafontia cuencana by Krebs (1993), P−2 H4 Pelejón 2, Galve, Teruel, Spain. I. Left M2 or M3, of Crusafontia cuencana Henkel and Krebs, 1969, Uña, La Huérguina Formation, Cuenca, Spain, (from Krebs 1993). Scale bars 1 mm.

Pectoral girdles and forelimbs of dinosaurs in left lateral view, depicting resting scapular and forelimb orientations in different dinosaurian groups as recommended according to the results of this study. In each case, solid horizontal line is parallel to long axis of sacrum. A. theropods without semilunate carpals (Dilophosaurus wetherilli, UCMP 37302). B. theropods with semilunate carpals other than Caudipteryx (Velociraptor mongoliensis, after reference [60]). C. Caudipteryx (C. sp., after reference [8]). D. ceratopsids (Styracosaurus albertensis, NMC 344). E. basal sauropodomorphs (Plateosaurus engelhardti, AMNH 6810). F. non-hadrosaurian ornithopods (Thescelosaurus neglectus, reference [62]). G. hadrosaurids (Parasaurolophus walkeri, after reference [48]). Angle labels: B = scapular orientation relative to long axis of sacrum. E = elbow angle. S = shoulder angle. W = wrist angle. See Materials and Methods section for descriptions of angles.

Figure description from paper: "A Cast of BES SC 999, the holotype of Besanosaurus leptorhynchus and (B) interpretative drawing (modified from Dal Sasso & Pinna, 1996). Foetal remains are highlighted with green lines. a astragalus, c calcaneum, Cl clavicle, Co coracoid, Fe femur, Fi Fibula, H humerus, i intermedium, Il Ilium, Is Ischium, P pubis, p pisiform, R radius, r radiale, S scapula, T Tibia, U Ulna, u ulnare; 2, 3, and 4, distal carpals and tarsals; II, III, IV, and V, metacarpals and metatarsals. The apostrophe (‘) indicates left elements. Scale bar represents 50 cm"

Figure description from paper: "A Cast of BES SC 999, the holotype of Besanosaurus leptorhynchus and (B) interpretative drawing (modified from Dal Sasso & Pinna, 1996). Foetal remains are highlighted with green lines. a astragalus, c calcaneum, Cl clavicle, Co coracoid, Fe femur, Fi Fibula, H humerus, i intermedium, Il Ilium, Is Ischium, P pubis, p pisiform, R radius, r radiale, S scapula, T Tibia, U Ulna, u ulnare; 2, 3, and 4, distal carpals and tarsals; II, III, IV, and V, metacarpals and metatarsals. The apostrophe (‘) indicates left elements. Scale bar represents 50 cm"

Figure description from paper: "A Cast of BES SC 999, the holotype of Besanosaurus leptorhynchus and (B) interpretative drawing (modified from Dal Sasso & Pinna, 1996). Foetal remains are highlighted with green lines. a astragalus, c calcaneum, Cl clavicle, Co coracoid, Fe femur, Fi Fibula, H humerus, i intermedium, Il Ilium, Is Ischium, P pubis, p pisiform, R radius, r radiale, S scapula, T Tibia, U Ulna, u ulnare; 2, 3, and 4, distal carpals and tarsals; II, III, IV, and V, metacarpals and metatarsals. The apostrophe (‘) indicates left elements. Scale bar represents 50 cm"

Figure description from the paper: "The segmented model of right lateral side of the skull of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard." References: Roberts, A.J.; Engelschiøn, V.S.; Hurum, J.H. (2022). "First three-dimensional skull of the Middle Triassic mixosaurid ichthyosaur Phalarodon fraasi from Svalbard, Norway". Acta Palaeontologica Polonica 67 (1): 51–62. DOI:https://doi.org/10.4202/app.00915.2021.