Cretaceous
Aquatic, water-plant eating relative of Nigersaurus. Rebbachisauridae.
A primitive ceratopsian with quill-like protofeathers, affording it defences like a porcupine. Archaeoceratopsidae.
A relative of Hyphalosaurus which reaches a length of 3 meters, similar in size to Champsosaurus. Hyphalosauridae.
A giant ammonite that has an array of ornamental spikes. Ancyloceratidae.
A primitive oviraptorosaur that is able to fly with large feathered wings. Stem Oviraptorosauria.
A relative of Kaprosuchus, which has a sabre-toothed-cat-like arrangement of fangs. Mahajangasuchidae.
An enantiornithine which is adapted to feed on flower nectar. Longipterygidae.
An oviraptorosaur which is able to ferment plant matter in its enlarged crop, much like a hoatzin. Oviraptorosauria.
Fully aquatic spinosaur, living in large rivers or estuaries, only returning to land in order to lay eggs. Spinosaurinae.
Burrow-digging ornithopod which has large clawed forelimbs for excavating its burrows. Parksosauridae.
Ankylosaur with a tail club that is pointed on each side. Ankylosaurinae.
A pachycephalosaur which has a tall, conical dome that is used solely for display, as opposed to physical combat. Pachycephalosauridae.
A small pterosaur which is adapted to clamber amongst the branches of flowering trees, drinking nectar. Pterodactyloidea.
An abyssal-dwelling relative of Enchodus, having anglerfish-like bioluminescent lures. Enchodontidae.
An abyssal-dwelling relative of Lepidotes, having somewhat reduced scalation. Semionotiformes.
An abyssal-dwelling relative of Dercetis, having fewer, much larger teeth. Dercetidae.
An abyssal-dwelling relative of Ancyloceras, feeding like a vampire-squid. Ancyloceratidae.
A pachycephalosaur species with large spikes resembling those of Stygimoloch, which are still present when the animal is mature. Pachycephalosauridae.
A titanosaur which has an extensive covering of spiny osteoderms, affording it some protection from predators. Lithostrotia.
A relictual xenacanthid shark occurring in Madagascar, having a ghost lineage since the Triassic. Xenacanthidae.
An ankylosaur which is aquatic much like a hippopotamus, and accordingly has shorter legs and an even stouter body for buoyancy. Ankylosaurinae.
A relative of Troodon that has become an obligate herbivore, even possessing a beak. Troodontidae.
A Pachyrhizodus-like fish which is similar to a tuna, in its size, and adaptations for speed. Pachyrhizodontidae.
A fossil sturgeon that has back plates resembling those of a stegosaur. Acipenseriformes.
A dromaeosaur that is adapted for swimming in order to prey on fish. Unenlagiinae.
A relictual stegosaur inhabiting India, that has evolved in isolation since India separated from Gondwana. Stegosauridae.
A giant alvarezsaur, perhaps 4 meters long. Alvarezsauridae.
A lambeosaur which possesses both a hollow crest and a large, Gryposaurus-like nose. Lambeosaurinae.
A filter-feeding aristonectid which reaches a greater size than any other plesiosaurian, perhaps 18m. Aristonectidae.
Tree-dwelling dromaeosaur, which is not a Microraptorian. Velociraptorinae.
A Maastrichtian relative of Pteranodon which possesses a distinctive crest. Pteranodontidae.