Animal | Age (Millions of Years Ago) | Type | Significance |
Haikouichthys | ~530 | Fish | Earliest known fish-like vertebrate, providing insights into the early evolution of vertebrates. |
Eusthenopteron | ~385 | Amphibian | Early lobe-finned fish, considered a close relative of tetrapods and illustrating early vertebrate evolution. |
Tiktaalik | ~375 | Amphibian | Transitional fossil between fish and tetrapods, providing insights into the evolutionary steps to land adaptation. |
Cladoselache | ~370 | Shark | One of the earliest known sharks, characterized by its streamlined body and fossilized remains found in North America. |
Hylonomus | ~315 | Sauropsid | One of the earliest known sauropsids, resembling modern lizards in some features. |
Archaeothyris | ~306 | Synapsid | One of the earliest known synapsids, representing the transition from reptilian ancestors to synapsids. |
Paleothyris | ~306 | Reptile | Early reptile considered a basal member of reptiliomorphs, the group from which reptiles evolved. |
Edaphosaurus | ~303-272 | Synapsid | Early synapsid known for its sail-like structure, showcasing herbivorous adaptations. |
Dimetrodon | ~295-272 | Synapsid | Iconic sail-backed synapsid, not a direct ancestor of mammals but an important part of synapsid evolution. |
Araeoscelis | ~290 | Sauropsid | Early diapsid reptile known for its elongated body and adaptations for terrestrial life. |
Proterosuchus | ~252 | Archosaur | One of the earliest archosaurs, known for its semi-aquatic lifestyle and sprawling gait. |
Procynosuchus | ~252 | Synapsid | Early cynodont, a group of advanced synapsids that eventually gave rise to mammals. |
Dongusuchus | ~251 | Archosaur | An early archosauriform, contributing to our understanding of the diversity and distribution of early archosaurs. |
Chaohusaurus | ~250-248 | Ichthyosaur | Early ichthyosaur that provides insight into the early evolution and adaptation of ichthyosaurs to aquatic life. |
Keichousaurus | ~248-240 | Sauropterygian | One of the earliest known sauropterygians, providing insights into the early adaptations to marine life. |
Cartorhynchus | ~248 | Ichthyosaur | One of the earliest known ichthyosaurs, showcasing transitional features between terrestrial reptiles and more derived ichthyosaurs. |
Erythrosuchus | ~247 | Archosaur | A large, early archosaur, providing insights into the evolution of terrestrial apex predators. |
Nyasasaurus | ~243 | Dinosaur | Potentially the earliest known dinosaur, from the Middle Triassic, though its classification is debated. |
Mixosaurus | ~242-235 | Ichthyosaur | One of the more well-known early ichthyosaurs, showcasing a blend of features found in both primitive and more advanced ichthyosaurs. |
Turfanosuchus | ~242 | Archosaur | An early archosaur that helps bridge the morphological gap between more primitive archosauriforms and later archosaurs. |
Nothosaurus | ~240-210 | Sauropterygian | Early sauropterygian that bridges the gap between primitive forms and more advanced plesiosaurs. |
Prestosuchus | ~238 | Archosaur | A well-known early archosaur that provides insight into the morphology and lifestyle of early terrestrial predators. |
Megalancosaurus | ~237-201 | Squamate | An early lizard-like reptile from the Late Triassic, showing some features similar to those of squamates. |
Staurikosaurus | ~233 | Dinosaur | Early theropod. |
Saturnalia | ~233 | Dinosaur | Early sauropodomorph. |
Buriolestes | ~233 | Dinosaur | Early sauropodomorph. |
Eoraptor | ~231-228 | Dinosaur | One of the earliest known dinosaurs. |
Herrerasaurus | ~231-228 | Dinosaur | One of the earliest theropods. |
Eodromaeus | ~231 | Dinosaur | Early theropod. |
Panphagia | ~231 | Dinosaur | One of the earliest sauropodomorphs. |
Preondactylus | ~228-216 | Pterosaur | One of the earliest and most primitive pterosaurs known. |
Scleromochlus | ~228-210 | Pterosaur | Considered a close relative or an early form of pterosaur. |
Pisanosaurus | ~228 | Dinosaur | One of the earliest ornithischians. |
Guaibasaurus | ~228 | Dinosaur | Early dinosaur that may belong to the theropod lineage. |
Adelobasileus | ~225 | Mammal | Early mammal-like cynodont, considered to be one of the closest relatives to true mammals. |
Postosuchus | ~221 | Archosaur | A later archosaur but still early in the lineage leading to crocodylomorphs. |
Hesperosuchus | ~220 | Crocodylomorph | One of the earliest known crocodylomorphs, showing transitional features between early archosaurs and later crocodilians. |
Sphenosuchus | ~220 | Crocodylomorph | Early crocodylomorph known for its slender build and adaptations for hunting in aquatic environments. |
Eudimorphodon | ~210 | Pterosaur | Early pterosaur with well-preserved remains, showing early adaptations for flight. |
Thalassiodracon | ~201 | Plesiosaur | One of the earliest plesiosaurs, showing a mix of primitive and derived features. |
Attenborosaurus | ~201 | Plesiosaur | Early plesiosaur. |
Megazostrodon | ~200 | Mammal | One of the earliest known mammals, representing the transition from reptilian ancestors to true mammals. |
Morganucodon | ~200 | Mammal | Early mammal with fossil evidence of fur and differentiated teeth, showing early mammalian adaptations. |
Plesiosaurus | ~199-175 | Plesiosaur | The genus after which the group is named, with well-preserved specimens providing key anatomical insights. |
Scelidosaurus | ~193 | Ankylosaur | One of the earliest known armored dinosaurs, showcasing early features that later ankylosaurs evolved from. |
Huayangosaurus | ~168 | Stegosaur | One of the earliest known stegosaurs, found in China. |
Tingitana | ~166 | Squamate | One of the earliest well-preserved squamates from the Middle Jurassic. |
Yinlong | ~161 | Ceratopsian | One of the earliest known ceratopsians, found in China. |
Protopteryx | ~160 | Bird | Early bird from China, providing insights into the early stages of bird evolution. |
Kentrosaurus | ~155 | Stegosaur | Early stegosaur from Africa, known for its smaller size and well-developed defensive spikes on its body. |
Gargoyleosaurus | ~155 | Ankylosaur | Early ankylosaur known from North America. |
Archaeopteryx | ~150 | Bird | One of the most famous early birds, known from fossils in Germany, showcasing a mix of reptilian and avian features. |
Eoconfuciusornis | ~130 | Bird | Early bird from China, bridging the gap between non-avian dinosaurs and modern birds. |
Psittacosaurus | ~125-100 | Ceratopsian | Early ceratopsian known for its parrot-like beak and relatively primitive features compared to later ceratopsians. |