252 — 201 Ma

Triassic

Life recovers from near-total extinction as the first dinosaurs and mammals appear.

Laurasia

Coelophysis and Desmatosuchus on a monsoonal Laurasian floodplain

On a monsoonal Late Triassic floodplain of northern Pangaea, slender Coelophysis bauri dash along the edge of a muddy channel while the heavily armored aetosaur Desmatosuchus roots through wet sediment nearby. This scene evokes the Chinle-type landscapes of Laurasia about 220–210 million years ago, where seasonal rivers crossed red-bed basins under hot, strongly seasonal climates. Horsetails, cycads, and conifers such as Voltzia-like trees reflect the pre-flowering plant world that supported these early dinosaur-dominated ecosystems.

Plateosaurus browsing in Late Triassic European conifer woodlands

In a seasonal woodland of Late Triassic Central Europe, several Plateosaurus—long-necked early sauropodomorph dinosaurs about 7–8 meters long—rear up to browse from conifers and ginkgophytes, while bennettitaleans, ferns, and horsetails dot the red, dusty floodplain. This scene represents the Norian Stage, roughly 220–210 million years ago, when central Laurasia lay within the vast interior of Pangaea and experienced strongly seasonal, semi-arid conditions. Plateosaurus was among the largest herbivores of its ecosystem, using its flexible neck, grasping hands, and bipedal reach to exploit vegetation above the low understory.

Basaltic lava flows in the Late Triassic North American rift

At the close of the Triassic, about 201 million years ago, eastern North America lay within a fault-bounded rift basin as the Central Atlantic Magmatic Province (CAMP) began to erupt. This scene shows incandescent tholeiitic basalt spilling from linear fissures across red mudstones and shallow lake margins, while sparse Pelourdea-like cheirolepidiacean conifers, ferns, and horsetails cling to a stressed volcanic landscape. Tiny coelophysoid theropods or a phytosaur at the water’s edge emphasize the scale of the eruptions and the environmental upheaval that accompanied the end-Triassic mass extinction.

Phytosaur Machaeroprosopus at a stagnant Triassic desert waterhole

In the late Triassic, about 220–210 million years ago, seasonal droughts could reduce rivers in southwestern North America to shrinking, stagnant waterholes like this one. Dominating the pool is the phytosaur Machaeroprosopus, a crocodile-shaped archosaur with nostrils set high on its snout, while a stranded Koskinonodon temnospondyl and dying semionotiform fishes reveal the harsh toll of desiccation in Laurasia’s arid monsoonal interior. Sparse horsetails, ferns, conifers, cycads, and bennettitalean seed plants cling to the damp margins, reflecting a world long before grasses or flowering plants appeared.

Giant Shonisaurus ichthyosaurs swimming in the Panthalassan Ocean

In the Late Triassic, about 230–210 million years ago, giant ichthyosaurs of the genus Shonisaurus glide through the deep offshore waters of Panthalassa along the western margin of Laurasia. Their streamlined bodies, long snouts, and crescent-shaped tails reveal these reptiles as highly specialized open-ocean swimmers, moving above a steep basin wall in a vast blue pelagic realm. Floating shell-rich debris dominated by the thin bivalve Halobia and schools of small marine fishes add to the scene, evoking the rich but still distinctly Mesozoic ecosystems that flourished long before modern whales or seabirds appeared.

Nothosaurus patrolling the shallow Middle Triassic Muschelkalk sea

In the shallow, sunlit waters of the Middle Triassic Muschelkalk sea, about 245–240 million years ago, a Nothosaurus patrols above a carbonate seafloor dotted with crinoids, bivalves, ammonoids, and small fishes. This scene from the Germanic Basin of Laurasia shows characteristic marine life including the stalked crinoid Encrinus liliiformis, ribbed Myophoria clams, Ceratites ammonoids, and silvery Perleidus, all part of a warm epicontinental shelf ecosystem where early marine reptiles became important predators.

Scleractinian corals and sponges on a Triassic Tethyan reef

On a warm Tethyan shelf along the Laurasian margin in the Late Triassic, about 220–210 million years ago, low reef knolls of scleractinian corals such as Retiophyllia and Volzeia are bound together by bulbous sphinctozoan sponges and microbial crusts. Small ganoid fish, including Peltopleurus, weave through the branching framework while smooth-shelled ammonoids like Arcestes hover in the clearer water beyond. These Norian reefs differed from modern coral reefs, relying on a distinctive partnership of early reef-building corals, chambered sponges, and microbial binders to construct carbonate-rich bioherms on shallow tropical seafloors.

Placodus crushing shells in a shallow Tethyan lagoon

In a warm, shallow Triassic lagoon along the Tethyan margin of Laurasia, a Placodus browses the shell-strewn bottom, using its projecting front teeth to pry up prey and its broad crushing teeth to crack open thick-shelled bivalves such as Megalodon. Above, hybodont sharks patrol the clear water while carbonate sand, shell debris, and low algal mats cover the seafloor. This scene reflects a Middle to Late Triassic marine ecosystem, roughly 240–220 million years ago, when placodont reptiles were specialized durophages adapted to feeding on hard-shelled invertebrates in coastal shelf and lagoon environments.

Tethys

Early Triassic microbial mats and stromatolite tidal flats

In the earliest Triassic, about 252 million years ago, broad tidal flats along the Tethys Ocean were often dominated by dark microbial mats and low stromatolitic domes spread across sun-baked carbonate mud. This scene shows a harsh, low-diversity shoreline in the aftermath of the end-Permian mass extinction, with only a few small ceratitid ammonoids drifting or stranded in shallow tidal channels. Such microbial-rich coastal environments record a stressed world in recovery, before complex reef communities fully re-established in Triassic seas.

Middle Triassic Placodus hunting on carbonate shell flats

On a sunlit Middle Triassic carbonate flat of the Tethys, about 245–235 million years ago, a stout placodont reptile, Placodus, searches the shell-rich bottom for hard-shelled prey. Its broad, crushing jaws are well suited to feeding on bivalves such as Myophoria, while spiny decapod crustaceans like Pemphix scavenge among the broken shells on the lime-mud and sand seafloor. This scene reflects the warm, shallow tropical platforms that spread across the Tethyan realm as marine ecosystems recovered and diversified after the end-Permian mass extinction.

Besanosaurus ichthyosaur hunting ammonoids in open Tethys waters

In the warm open waters of the Middle to early Late Triassic Tethys, about 240–235 million years ago, a long-snouted Besanosaurus darts through a scattering of Trachyceras ammonoids and swift Birgeria fishes. This scene captures a pelagic ecosystem above a stratified intraplatform basin, where sunlit cobalt surface waters gave way downward to darker, oxygen-poor depths. Besanosaurus was a specialized ichthyosaur, one of the dolphin-shaped marine reptiles that flourished in Triassic seas, while Trachyceras and Birgeria represent the abundant ammonoids and ray-finned fishes that shared this recovering post-Permian ocean.

Lariosaurus and Neusticosaurus in Monte San Giorgio Triassic lagoon

In a quiet lagoon of the western Tethys about 242–237 million years ago, a long-necked Lariosaurus snaps through a school of gleaming Peltopleurus while the smaller Neusticosaurus hovers low over soft carbonate mud. This scene is based on the famous Middle Triassic fossil deposits of Monte San Giorgio, where shallow tropical waters preserved fishes, crustaceans such as Antrimpos, bivalves, and early sauropterygian reptiles in remarkable detail. Together these animals illustrate the rapid recovery and diversification of marine ecosystems after the end-Permian mass extinction.

Peteinosaurus pterosaurs and Plateosaurus on Late Triassic arid coast

On a hot, arid shoreline along the western Tethys in the latest Triassic, about 205–201 million years ago, small early pterosaurs called Peteinosaurus skim low over warm, shallow surf above pale limestone benches and evaporitic tidal flats. Inland, a much larger Plateosaurus browses among sparse bennettitalean or cycad-like plants and Triassic conifers, illustrating the contrast between agile fliers and one of the era’s prominent basal sauropodomorph dinosaurs. The scene captures a carbonate-platform coast of the Rhaetian Age, where saline flats, dolostone muds, and drought-tolerant vegetation reflect the harsh subtropical climates common around the Tethyan margins.

Norian coral and sponge reef on Tethyan carbonate slope

A warm fore-reef on the western Tethyan margin during the Late Triassic Norian, about 220–210 million years ago, is shown descending from a coral–sponge reef into a pale carbonate talus slope. Branching scleractinian corals such as Retiophyllia and dome-shaped Margarophyllia grow among conspicuous sphinctozoan sponges, while clustered Encrinus liliiformis crinoids filter food from clear tropical water above the reef base. Small schools of the ray-finned fish Peltopleurus flash overhead, capturing a stage in reef evolution when coral–sponge communities were rebuilding complex marine ecosystems long before modern-style reefs appeared.

Ticinosuchus rauisuchian on waterlogged Carnian Pluvial coastal plain

On a storm-lashed coastal plain along the western Tethys during the Carnian Pluvial Episode, about 233 million years ago, a slender rauisuchian, Ticinosuchus, moves cautiously through waterlogged red-brown mud beside a swollen estuarine channel. Around it grow dense stands of Equisetites horsetails, Cladophlebis fern-like foliage, and scattered Voltzia conifers—plants typical of Late Triassic wetlands before the rise of flowering plants and grasses. The scene captures a warm, monsoonal world in which seasonal flooding reshaped low coastal floodbasins at the edge of the Tethyan seaway.

Long-necked Tanystropheus hunting in Late Triassic Tethyan lagoon

On the shore of a warm Late Triassic lagoon in the western Tethys, an adult Tanystropheus longobardicus stands half-submerged in shallow, carbonate-rich water, its remarkably elongated striped neck stretched low above the surface as it searches for prey. Around it lie pale micritic limestone ledges, tidal-flat muds, sparse Pterophyllum cycadophytes, and Voltzia conifers typical of arid coastal settings on Tethyan carbonate platforms. Dating to roughly 237–227 million years ago, this strange reptile was not a dinosaur but a specialized archosauromorph, famous for a neck that made up more than half its total body length.

Gondwana

Late Triassic Antarctic Dicroidium seed-fern forest

In the Late Triassic, about 230–201 million years ago, high-latitude Antarctica lay within Gondwana yet supported dense Dicroidium seed-fern forests rather than ice sheets. This scene reconstructs a cool, humid floodplain in the Transantarctic region, where forked fronds of Dicroidium mingle with slender early conifers, true ferns, horsetails, and damp leaf litter along a dark freshwater channel. Such polar woodlands reflect the greenhouse climate of Triassic Earth, when even southern polar regions experienced strongly seasonal light but remained largely ice-free.

Saurosuchus predator hunting Hyperodapedon on Ischigualasto plains

On a hot, dusty floodplain of the Ischigualasto–Villa Unión Basin in what is now northwestern Argentina, a large rauisuchian predator, Saurosuchus galilei, strides past a wary group of Hyperodapedon rhynchosaurs. This scene represents southwestern Gondwana during the Late Triassic (Carnian, about 231–228 million years ago), when seasonal river plains, red mudstones, and patchy stands of Dicroidium seed ferns and conifers supported diverse reptile-dominated ecosystems before dinosaurs became fully dominant.

Temnospondyl Xenotosuchus in seasonal Gondwanan waterhole

On a hot Late Triassic floodplain of Gondwana, around 230–210 million years ago, a broad-headed temnospondyl amphibian resembling Xenotosuchus waits half-submerged in a shrinking seasonal waterhole as lungfish cruise through the murky shallows. Cracked red mud, sparse horsetails, seed ferns, and shell-rich conchostracan patches reflect the strongly seasonal climates common across southern Pangaea’s interior basins. Such scenes capture the persistence of ancient amphibian lineages in drought-prone freshwater habitats even as Triassic ecosystems were becoming increasingly dominated by reptiles.

Early dinosaurs Eoraptor and Panphagia at dusk

At dusk on a Late Triassic riverbank in what is now northwestern Argentina, two of the earliest dinosaurs move through a ribbon of lush vegetation: the small theropod-like Eoraptor lunensis and the slightly larger basal sauropodomorph Panphagia protos. This scene is set in the Carnian Stage, about 231–228 million years ago, within the Ischigualasto-Villa Unión Basin, where seasonal rivers crossed red, ash-dusted floodplains under a warm, semi-arid climate. Ferns, Dicroidium seed ferns, and Neocalamites reeds frame these lightly built early saurischians, highlighting a world before flowering plants and long before giant dinosaurs came to dominate Jurassic landscapes.

Ichthyosaur Cymbospondylus hunting fish in Triassic Tethys

In the open waters off northern Gondwana during the Late Triassic, about 235–220 million years ago, a single Cymbospondylus surges upward beneath a school of small ray-finned fishes while nearby Arcestes ammonoids drift in the plankton-rich blue. This early ichthyosaur, with its long tooth-filled snout, large eyes, and streamlined body powered by paddle-like limbs and a crescent tail, was among the top marine predators of its time. The scene captures the growing diversity of Triassic seas as marine ecosystems recovered and expanded after the end-Permian mass extinction.

Scleractinian coral reef recovery in northern Gondwana

In the warm, shallow waters of the northern Gondwanan margin during the Late Triassic, about 237–201 million years ago, low patch reefs spread across a pale carbonate seafloor as marine ecosystems recovered and diversified after the end-Permian crisis. This scene shows scleractinian corals such as Retiophyllia and Volzeia forming modest reef knolls among hypercalcified sponges, microbial crusts, stalked crinoids, and large megalodontid bivalves anchored in the sediment. Unlike modern coral reefs, these Triassic communities were often more open and patchy, reflecting an important transitional stage in the rebuilding of complex reef habitats along the Tethyan shelf.

Nothosaur hunting Saurichthys in a Tethyan lagoon

In a warm Late Triassic lagoon along Gondwana’s northern Tethyan margin, a nothosaur lunges through shallow turquoise water after the sleek predatory fish Saurichthys, stirring sand and mud above a shell-strewn bottom. Around them drift ribbed ammonoids such as Tropites, while clusters of Myophoria bivalves and patches of green algae dot the lagoon floor beneath a dry, seasonally harsh shoreline. This scene captures a marine ecosystem from about 237–227 million years ago, when semi-aquatic reptiles like Nothosaurus hunted in coastal waters fringing the supercontinent Pangaea.

Panthalassa Ocean

Cymbospondylus hunting Perleidus in Triassic Panthalassa Ocean

In the open waters of Triassic Panthalassa, about 247–237 million years ago, a long-bodied Cymbospondylus surges upward beneath a scattering school of Perleidus while small ribbed Trachyceras ammonoids drift near the sunlit surface. This scene captures an early stage in ichthyosaur evolution, when these marine reptiles were already formidable pelagic predators but still retained a more elongated, less tuna-like body than their later descendants. The immense blue expanse around them reflects the scale of Panthalassa, the vast global ocean that dominated Earth during the Middle Triassic.

Late Triassic Volzeia coral reef on volcanic seamount

On a shallow volcanic seamount in the Panthalassa Ocean, patchy reef communities spread across dark basalt ledges and pale carbonate rubble in the Late Triassic, about 237–201 million years ago. Early scleractinian corals such as Volzeia, sponge-microbial buildups, and stalked crinoids like Holocrinus represent marine ecosystems recovering and diversifying after the end-Permian mass extinction, while small shrimp-like crustaceans shelter among the reef framework. The scene captures how isolated oceanic guyots could host surprisingly rich tropical communities far from the continental margins of Pangaea.

Deep Triassic Panthalassa seafloor with radiolarian abyssal rain

Far below the surface of the Triassic Panthalassa Ocean, about 230–210 million years ago, a slow “rain” of microscopic radiolarians and organic debris drifts onto a quiet abyssal plain 4–5 km deep. The seafloor is a broad expanse of fine siliceous mud—the precursor to radiolarian chert—marked only by a few faint worm trails, reflecting a deep marine setting where oxygen was limited and animal activity was sparse. This scene captures one of the great open-ocean environments of the Mesozoic: a dark, low-energy basin dominated not by large animals, but by the steady accumulation of plankton skeletons from the waters above.

Late Triassic monsoonal storm hitting Voltzia conifer shoreline

A violent monsoonal storm lashes a Late Triassic shoreline on the margin of Panthalassa, about 230–210 million years ago, where brown sheet-floods race across red sediment flats toward a dark, wave-battered volcanic coast. Wind-bent stands of Voltzia conifers dominate the open woodland, accompanied by cycad-like and bennettitalean plants adapted to a seasonally dry climate. This scene captures the dynamic meeting of arid coastal plains, active volcanism, and the immense open ocean that surrounded Pangaea.

Panthalassa volcanic island arc with Late Triassic reefs

On a volcanic island arc in the Late Triassic Panthalassa Ocean, roughly 230–210 million years ago, dark basalt cliffs and ash-rich tuffs rise beneath a steaming andesitic stratovolcano, while surf washes a narrow carbonate reef fringe along the shore. In the clear shallows, early scleractinian corals and calcareous sponges form patchy reef communities inhabited by neopterygian fishes and drifting ammonoids, and beyond the breakers a small ichthyosaur surfaces in the open sea. The scene captures a world of active subduction-zone volcanism and recovering marine ecosystems in Earth’s vast global ocean.

Giant Shonisaurus and Saurichthys in Late Triassic Panthalassa

In the Late Triassic, about 220–210 million years ago, a giant Shonisaurus glides over a Panthalassan shelf seafloor strewn with dense beds of the bivalve Monotis, while sleek predatory Saurichthys patrol the water above. This scene captures a productive offshore ecosystem along the margin of western Pangaea, where ichthyosaurs had already evolved into some of the largest marine reptiles of their time. The shell-rich muds, scattered volcanic debris, and blue-green water hint at an active convergent margin shaped by upwelling and nearby island-arc volcanism.

Eudimorphodon pterosaurs soaring over Triassic basalt lagoon cliffs

On a volcanic island coast of the Late Triassic, about 210 million years ago, small pterosaurs called Eudimorphodon soar along dark basalt cliffs above a shallow Panthalassan lagoon. With wingspans of roughly 1 metre, long vane-tipped tails, and distinctive multicusped teeth adapted for catching fish, these early fliers likely fed along warm coastal margins like this one. Sparse ferns, cycads, and conifer-like shrubs cling to the ledges, while guano-streaked rocks and an active island-arc volcano emphasize the dynamic setting of a Triassic ocean world.

Metoposaurus predator lurking in Triassic Panthalassa estuary shallows

In a Late Triassic estuary on the margin of Panthalassa, about 230–210 million years ago, a large Metoposaurus lies nearly hidden in muddy shallows, its broad, flattened skull and upward-facing eyes adapted for ambush in turbid water. Dense stands of Equisetites horsetails fringe the river mouth, while beyond them the coastal plain supports conifers, seed ferns, and cycads typical of Triassic landscapes. This scene captures a temnospondyl amphibian in one of the humid wetland habitats that persisted along parts of Pangaea’s storm-swept Pacific-facing coast.

Next Period

Jurassic