Rhynchosaurs were amongst the most plentiful plant-eaters of their time, spreading out throughout much of the supercontinent Pangea and in some locations comprising the huge bulk of fossilized vertebrates.

Their specialized feeding device– consisting of a toothless beak and rows of grinding teeth– permitted them to process hard plants and control terrestrial environments.

“Rhynchosauria, an early diverging clade within Archosauromorpha, is represented by a number of types dispersed generally throughout the Middle and Late Triassic, though their origin go back to the Early Triassic,” stated Universidade Federal de Santa Maria paleontologist Jeung Hee Schiefelbein and associates.

“Rhynchosaurs covered almost the whole of Pangea, and their fossil record extends throughout a number of contemporary areas, consisting of Brazil, Argentina, Canada, the United States, Zimbabwe, Tanzania, South Africa, Madagascar, India, England and Scotland.”

“By the Late Triassic, rhynchosaurs accomplished an almost worldwide circulation, playing a substantial function as main customers in terrestrial environments.”

“Owing to their abundance, specifically in Late Triassic systems, rhynchosaurs are likewise crucial biostratigraphic markers, with rhynchosaurs making up to 90% of the vertebrate fossils in some outcrops.”

The holotype specimen of Isodapedon varzealis was uncovered at the Várzea do Agudo website in the Brazilian state of Rio Grande do Sul.

The fossil go back around 230 million years to the Carnian age of the Triassic duration.

The upper jaw of Isodapedon varzealis functions in proportion tooth-bearing locations– an uncommon quality amongst its family members– in addition to a distinct setup of the lower jaw that recommends it fed in a different way from other recognized rhynchosaurs.

A phylogenetic analysis suggests that the types lies outdoors formerly acknowledged South American members of its subgroup, referred to as hyperodapedontines.

The findings challenge the standard category of these reptiles and supports a narrower meaning of the widely known genus Hyperodapedonrestricting it to its initial type types.

The outcomes likewise indicate a wider and more complicated evolutionary radiation of rhynchosaurs than formerly valued.

Carefully associated types appear to have actually spread out extensively throughout southwestern Gondwana– the southern part of Pangea– while preserving reasonably conservative body strategies.

Isodapedon varzealisspecial mix of craniomandibular characters, consisting of balanced maxillary tooth-bearing locations and autapomorphic dentary functions, identifies it from synchronous types such as Macrocephalosaurus mariensis and Hyperodapedon sp.,” the scientists stated.

“These distinctions most likely show divergent eco-friendly techniques within a varied herbivorous guild, which might show specific niche partitioning throughout a time of vibrant ecological and flower modifications connected with the Carnian Pluvial Episode.”

“Moreover, its affinities with early diverging hyperodapedontines from Argentina and perhaps Zimbabwe indicate a broad, morphologically conservative radiation throughout southwestern Gondwana, highlighting environmental stability before the introduction of more obtained and geographically limited family trees.”

A paper explaining the discovery was released April 15 in the journal Royal Society Open Science

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Jeung Hee Schiefelbein et al2026. A brand-new hyperodapedontine rhynchosaur from a cynodont-dominated website (Upper Triassic) of southern Brazil. R Soc Open Sci 13 (4 ): 260176; doi: 10.1098/ rsos.260176