description

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.

Various fossils pertaining to the holotype of the Triassic ichthyosaur Toretocnemus californicus. This image is derived from plate 24 in Merriam (1903), done by an uncredited artist. The arrangement of the individual figures has been modified from the original. Original description: Toretocnemus californicus n. gen. and sp. Figures reproduced natural size from the type specimen. Fig. 1. — Inferior side of right posterior limb. t, tibia. Fig. 2. — Right anterior limb. r, radius. Fig. 3.— Pelvic arch. Fig. 4. — Middle dorsal vertebrae and a rib from the same region.

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

Reconstruceted skull of Dubreuillosaurus illustrating known (white) and unknown (grey) material. Scale bar is 10cm. Based of figures and description of Allain (2002) "Discovery of megalosaur (Dinosauria, Theropoda) in the middle Bathonian of Normandy (France) and its implications for the phylogeny of basal Tetanurae"

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.

Life restoration of Kansaignathus sogdianus. Modified from drawing of generic dromaeosaur to match figures of the holotype mandible in the description and skeletal reconstructions of related dromaeosaurs.

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.

A restoration of Rinconsaurus compared to a human , • Based proportionally on fossil elements and skeletal reconstruction featured in the Rinconsaurus description,[1] with missing parts based on other titanosaur reconstructions. The remains of Rinconsaurus represent two adults and a juvenile all of which are incomplete; some of the proportions shown here, such as the neck, limb lengths, and skull shape are not certain. • Osteroderms are not yet known in Rinconsaurus. The osteoderms shown here are based loosely on Mendozasaurus.[2] Osteoderms are known from at least 10 titanosaur genera spread across the family tree but it's not clear if all titanosaurs had them.[3] Titanosaur osteoderms are rare and their layout and position on the body are not certain. [4] • The colours and patterns, as with the majority of reconstructions of prehistoric creatures, are speculative. • Human silhouette approximately 180 cm tall. NOTE: I often update my images. If you want to have any of my images on a website, please (if possible) don’t host/save it to the website server. I’d prefer it if the image's Wikimedia URL is used. This means that if I update an image, it will be updated on the site as well. Thanks. References ↑ Coria, Jorge; B.J.G. Riga (2003). "Rinconsaurus caudamirus gen. et sp nov., a new titanosaurid (Dinosauria, Sauropoda) from the Late Cretaceous of Patagonia, Argentina". Revista Geologica de Chile 30 (2): 333–353. ISSN 0716-0208. Retrieved on 2007-05-21. ↑ González Riga B (2003) A new titanosaur (Dinosauria, Sauropoda) from the Upper Cretaceous of Mendoza, Argentina. Ameghiniana 40 (2) ↑ Carrano, M.T. and D’Emic, M.D. 2015 'Osteoderms of the titanosaur sauropod dinosaur Alamosaurus sanjuanensis Gilmore, 1922'. Journal of Vertebrate Paleontology. ↑ Vidal D, Ortega F, Sanz JL (2014) Titanosaur Osteoderms from the Upper Cretaceous of Lo Hueco (Spain) and Their Implications on the Armor of Laurasian Titanosaurs. PLoS ONE 9(8): e102488. doi:10.1371/journal.pone.0102488

A restoration of Rinconsaurus compared to a human , • Based proportionally on fossil elements and skeletal reconstruction featured in the Rinconsaurus description,[1] with missing parts based on other titanosaur reconstructions. The remains of Rinconsaurus represent two adults and a juvenile all of which are incomplete; some of the proportions shown here, such as the neck, limb lengths, and skull shape are not certain. • Osteroderms are not yet known in Rinconsaurus. The osteoderms shown here are based loosely on Mendozasaurus.[2] Osteoderms are known from at least 10 titanosaur genera spread across the family tree but it's not clear if all titanosaurs had them.[3] Titanosaur osteoderms are rare and their layout and position on the body are not certain. [4] • The colours and patterns, as with the majority of reconstructions of prehistoric creatures, are speculative. • Human silhouette approximately 180 cm tall. NOTE: I often update my images. If you want to have any of my images on a website, please (if possible) don’t host/save it to the website server. I’d prefer it if the image's Wikimedia URL is used. This means that if I update an image, it will be updated on the site as well. Thanks. References ↑ Coria, Jorge; B.J.G. Riga (2003). "Rinconsaurus caudamirus gen. et sp nov., a new titanosaurid (Dinosauria, Sauropoda) from the Late Cretaceous of Patagonia, Argentina". Revista Geologica de Chile 30 (2): 333–353. ISSN 0716-0208. Retrieved on 2007-05-21. ↑ González Riga B (2003) A new titanosaur (Dinosauria, Sauropoda) from the Upper Cretaceous of Mendoza, Argentina. Ameghiniana 40 (2) ↑ Carrano, M.T. and D’Emic, M.D. 2015 'Osteoderms of the titanosaur sauropod dinosaur Alamosaurus sanjuanensis Gilmore, 1922'. Journal of Vertebrate Paleontology. ↑ Vidal D, Ortega F, Sanz JL (2014) Titanosaur Osteoderms from the Upper Cretaceous of Lo Hueco (Spain) and Their Implications on the Armor of Laurasian Titanosaurs. PLoS ONE 9(8): e102488. doi:10.1371/journal.pone.0102488

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.

Skull diagram showing the known material of Aardonyx. Based on photographs and measurements in original description and supplementary material. Scale bar = 10 cm