{"product_id":"hyperodapedon-sanjuanensis","title":"Hyperodapedon sanjuanensis","description":"\u003cdiv class=\"qMYqUG_convSearchResultHighlightRoot\"\u003e\n\u003cdiv class=\"\" data-turn-id-container=\"request-6a5dbd41-4b78-83eb-bdb1-9c8884dec0d4-31\" data-is-intersecting=\"true\"\u003e\n\u003csection class=\"text-token-text-primary w-full focus:outline-none has-data-writing-block:pointer-events-none [\u0026amp;:has([data-writing-block])\u0026gt;*]:pointer-events-auto R6Vx5W_threadScrollVars scroll-mb-[calc(var(--scroll-root-safe-area-inset-bottom,0px)+var(--thread-response-height))] scroll-mt-[calc(var(--header-height)+min(200px,max(70px,20svh)))]\" dir=\"auto\" data-turn-id=\"request-6a5dbd41-4b78-83eb-bdb1-9c8884dec0d4-31\" data-turn-id-container=\"request-6a5dbd41-4b78-83eb-bdb1-9c8884dec0d4-31\" data-testid=\"conversation-turn-498\" data-turn=\"assistant\"\u003e\n\u003cdiv class=\"text-base my-auto mx-auto pb-8 [--thread-content-margin:var(--thread-content-margin-xs,calc(var(--spacing)*4))] @w-sm\/main:[--thread-content-margin:var(--thread-content-margin-sm,calc(var(--spacing)*6))] @w-lg\/main:[--thread-content-margin:var(--thread-content-margin-lg,calc(var(--spacing)*16))] px-(--thread-content-margin)\"\u003e\n\u003cdiv data-conversation-screenshot-content=\"\" class=\"[--thread-content-max-width:40rem] @w-lg\/main:[--thread-content-max-width:48rem] mx-auto max-w-(--thread-content-max-width) flex-1 group\/turn-messages focus-visible:outline-hidden relative flex w-full min-w-0 flex-col agent-turn\"\u003e\n\u003cdiv class=\"flex max-w-full flex-col gap-4 grow\"\u003e\n\u003cdiv data-message-author-role=\"assistant\" data-message-id=\"ec5b61d7-0074-4f23-b19d-e48bf620dc7b\" data-turn-start-message=\"true\" dir=\"auto\" data-message-model-slug=\"gpt-5-6-thinking\" class=\"min-h-8 text-message relative flex w-full flex-col items-end gap-2 text-start break-words whitespace-normal outline-none keyboard-focused:focus-ring [.text-message+\u0026amp;]:mt-1\" tabindex=\"0\"\u003e\n\u003cdiv class=\"flex w-full flex-col gap-1 empty:hidden\"\u003e\n\u003cdiv class=\"markdown prose dark:prose-invert wrap-break-word w-full light markdown-new-styling\"\u003e\n\u003cp data-start=\"0\" data-end=\"758\" class=\"PDq2pG_selectionAnchorContainer\"\u003e\u003cem data-start=\"0\" data-end=\"32\"\u003e\u003cstrong data-start=\"1\" data-end=\"31\"\u003eHyperodapedon sanjuanensis\u003c\/strong\u003e\u003c\/em\u003e was a rhynchosaur archosauromorph reptile from the Late Triassic of South America, known from fossil remains recovered from the Ischigualasto Formation in San Juan Province, Argentina. Originally described by Sill in 1970, this taxon represents one of the most abundant and characteristic herbivores of the Carnian faunas of Ischigualasto, one of the most important geological units in the world for understanding terrestrial ecosystems before the definitive rise of dinosaur dominance. Although it lived alongside early dinosaurs, predatory archosaurs, cynodonts and dicynodonts, \u003cem data-start=\"614\" data-end=\"629\"\u003eHyperodapedon\u003c\/em\u003e was not a dinosaur, but a member of Rhynchosauria, a specialised lineage of herbivorous reptiles that is now completely extinct.\u003cspan aria-hidden=\"true\" class=\"PDq2pG_selectionAnchor\"\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp data-start=\"760\" data-end=\"1408\"\u003eGeologically, \u003cem data-start=\"774\" data-end=\"802\"\u003eHyperodapedon sanjuanensis\u003c\/em\u003e comes from continental deposits of the Late Triassic, mainly from the Carnian, approximately 231–229 million years ago. The Ischigualasto Formation records ancient landscapes of floodplains, river channels, developed soils and strongly seasonal environments, in which rhynchosaurs were dominant components of the vertebrate community. Recent studies have identified \u003cem data-start=\"1169\" data-end=\"1197\"\u003eHyperodapedon sanjuanensis\u003c\/em\u003e as the most abundant tetrapod in the Ischigualasto Formation, while other research indicates that remains of this rhynchosaur may represent around 60% of the specimens recovered from certain fossil assemblages.\u003c\/p\u003e\n\u003cp data-start=\"1410\" data-end=\"2170\"\u003eAnatomically, \u003cem data-start=\"1424\" data-end=\"1452\"\u003eHyperodapedon sanjuanensis\u003c\/em\u003e displayed the typical body plan of hyperodapedontine rhynchosaurs: a low, compact body, short but powerful limbs, a broad triangular skull, a robust anterior beak and highly modified jaws specialised for processing vegetation. Its skull was massive, with a powerful temporal region associated with well-developed jaw musculature. The maxillary and mandibular dental plates formed complex cutting and grinding surfaces, with multiple rows of teeth and a specialised occlusal system. This masticatory architecture enabled the animal to process resistant plant material, tough stems and fibrous vegetation in a Triassic world dominated by primitive conifers, ferns, horsetails, seed ferns and other non-flowering plants.\u003c\/p\u003e\n\u003cp data-start=\"2172\" data-end=\"2873\"\u003eFrom a morphometric perspective, \u003cem data-start=\"2205\" data-end=\"2233\"\u003eHyperodapedon sanjuanensis\u003c\/em\u003e was a small- to medium-sized rhynchosaur. A cautious reconstruction places its body length at approximately 1–1.5 metres, with a broad, low and robust body and a relatively low height compared with its total length. Its mass probably ranged from a few tens of kilograms to higher values in the largest adult individuals, although there is no single precise estimate comparable to those available for some better-known tetrapods. Its overall silhouette would have been that of a compact terrestrial herbivore with stable locomotion, better adapted to supporting a powerful bite and processing tough food than to rapid or cursorial movement.\u003c\/p\u003e\n\u003cp data-start=\"2875\" data-end=\"3549\"\u003eOne of the most significant aspects of \u003cem data-start=\"2914\" data-end=\"2942\"\u003eHyperodapedon sanjuanensis\u003c\/em\u003e is its specialised feeding apparatus. Studies using computed tomography and three-dimensional reconstruction of the holotype have allowed researchers to reassess the arrangement of the dental plates and the mechanics of the jaws, reinforcing the interpretation of an animal highly specialised for oral processing of vegetation. The osteological revision of the holotype skull published in \u003cem data-start=\"3332\" data-end=\"3355\"\u003eThe Anatomical Record\u003c\/em\u003e has also refined its anatomy and diagnosis, highlighting the importance of this species for understanding the diversity and evolution of hyperodapedontine rhynchosaurs during the Late Triassic.\u003c\/p\u003e\n\u003cp data-start=\"3551\" data-end=\"4482\"\u003e\u003cem data-start=\"3551\" data-end=\"3579\"\u003eHyperodapedon sanjuanensis\u003c\/em\u003e inhabited ecosystems shared with some of the most iconic vertebrates of Ischigualasto, including the large predator \u003cem data-start=\"3696\" data-end=\"3717\"\u003eSaurosuchus galilei\u003c\/em\u003e, the dicynodont \u003cem data-start=\"3734\" data-end=\"3758\"\u003eIschigualastia jenseni\u003c\/em\u003e, cynodonts such as \u003cem data-start=\"3778\" data-end=\"3791\"\u003eExaeretodon\u003c\/em\u003e, and early dinosaurs including \u003cem data-start=\"3823\" data-end=\"3838\"\u003eHerrerasaurus\u003c\/em\u003e and \u003cem data-start=\"3843\" data-end=\"3853\"\u003eEoraptor\u003c\/em\u003e. Within this ecosystem, \u003cem data-start=\"3878\" data-end=\"3893\"\u003eHyperodapedon\u003c\/em\u003e occupied the role of an abundant and ecologically important herbivore, probably forming an essential part of the trophic base for large Triassic carnivores. Its abundance within the formation suggests large populations and a high degree of adaptation to the available plant resources in these seasonal landscapes. In addition, a monospecific aggregation of juvenile individuals attributed to \u003cem data-start=\"4286\" data-end=\"4314\" data-is-only-node=\"\"\u003eHyperodapedon sanjuanensis\u003c\/em\u003e has recently been documented and interpreted as possible evidence of gregarious behaviour or shared use of shelters, although this hypothesis remains under discussion.\u003c\/p\u003e\n\u003cp data-start=\"4484\" data-end=\"4532\"\u003e\u003cstrong data-start=\"4484\" data-end=\"4532\"\u003eApproximate Hyperodapedon Replica Dimensions\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-start=\"4534\" data-end=\"4642\" data-is-last-node=\"\" data-is-only-node=\"\"\u003e\u003cstrong data-start=\"4534\" data-end=\"4565\"\u003e1:35 Scale — Complete Model\u003c\/strong\u003e\u003cbr data-start=\"4565\" data-end=\"4568\"\u003eLength: 31 mm\u003cbr data-start=\"4581\" data-end=\"4584\"\u003eHeight: 22 mm\u003cbr data-start=\"4597\" data-end=\"4600\"\u003eWidth: 19 mm\u003cbr data-start=\"4612\" data-end=\"4615\"\u003eSnout-to-tail length: 43 mm\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Dino and Dog","offers":[{"title":"1:35 \/ Sin imprimar","offer_id":62036085440780,"sku":"DC-1542-135-SINI","price":39.4,"currency_code":"EUR","in_stock":true},{"title":"1:35 \/ Imprimado","offer_id":62036085473548,"sku":"DC-1542-135-IMPRI","price":46.4,"currency_code":"EUR","in_stock":true},{"title":"1:35 \/ Pintado a mano","offer_id":62036085506316,"sku":"DC-1542-135-PINTA","price":172.0,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0672\/1106\/7660\/files\/Hyperodapedon_5.jpg?v=1786904116","url":"https:\/\/dinosauriacreatures.com\/en\/products\/hyperodapedon-sanjuanensis","provider":"Dinosauria Creatures","version":"1.0","type":"link"}