Best Synapsid
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Dimetrodon grandis is an extinct synapsid from the Early Permian of North America. It was a large terrestrial predator with differentiated teeth and elongated vertebral spines that supported a prominent sail along its back. Although frequently depicted alongside dinosaurs, Dimetrodon lived tens of m...
Lystrosaurus declivis is an extinct species of dicynodont therapsid known from southern Africa and dating to the interval around the Permian-Triassic boundary and Early Triassic. Like other members of its genus, it was a stocky, tusked herbivore with a beak adapted for cropping vegetation. Its abund...
Thrinaxodon liorhinus was a small cynodont synapsid from the Early Triassic, known principally from South Africa and Antarctica. Its skeleton combined reptile-like features with traits approaching those of mammals, including differentiated teeth and changes to the jaw and palate. Small pits and cana...
Cynognathus crateronotus was a large, predatory cynodont that lived during the Triassic Period and belonged to the synapsid lineage leading toward mammals. Fossils assigned to Cynognathus are particularly well known from South Africa, with related occurrences across parts of Gondwana, including Sout...
Inostrancevia alexandri is a large gorgonopsian therapsid from the Late Permian of European Russia. It was a predatory non-mammalian synapsid with an elongated skull, powerful jaws, and prominent saber-like upper canine teeth, while some reconstructed skulls exceed 50 centimeters in length. As one o...
Edaphosaurus pogonias was a large plant-eating synapsid from the Early Permian of North America. It had a relatively small skull, a deep body, and elongated neural spines supporting a prominent dorsal sail; many of those spines carried distinctive lateral crossbars. Although superficially similar to...
Lycaenops ornatus is an extinct gorgonopsian therapsid known from Late Permian rocks of South Africa's Karoo Basin. Like other gorgonopsians, it was a predatory non-mammalian synapsid with an elongated skull and enlarged, saber-like canine teeth adapted for seizing prey. Fossils of the species help...
Estemmenosuchus mirabilis is a large dinocephalian therapsid from the Middle Permian of what is now Russia. It is recognized by massive, outward-projecting bony structures on the skull, including prominent growths above and beside the head. As an early synapsid rather than a dinosaur, it helps docum...
Moschops capensis is a large, heavily built herbivorous therapsid from the middle Permian rocks of South Africa's Karoo Basin. It belonged to the dinocephalians, an early synapsid group that lived long before mammals and dinosaurs. Moschops is distinguished by a massively thickened skull roof, robus...
Cotylorhynchus romeri is the largest known caseian pelycosaur, a Permian herbivore from North America with a massive barrel-shaped body and disproportionately small head.
Ophiacodon mirus is an Early Permian synapsid from North America, one of the earliest large semi-aquatic predatory pelycosaurs in the vertebrate fossil record.
