Artist note:
Borissiakia is an extinct genus of chalicothere, a group of herbivorous, odd-toed ungulate (perissodactyl) mammals, that lived during the late Oligocene in Kazakhstan. They had claws that were likely used in a hook-like manner to pull down branches, suggesting they lived as bipedal browsers.
Artist note:
Hyaenodon gigas was the largest species of the genus Hyaenodon, a prehistoric carnivorous mammal of the now-extinct order Creodonta. It inhabited Asia, North America, and Europe from the Middle Eocene to the Early Miocene (42 to 11.4 million years ago). Despite its name, it was not related to modern hyenas, but rather resembled a large wolf or feline.
Artist note:
Paraceratherium is an extinct genus of hornless rhinocerotoids belonging to the family Paraceratheriidae. It is one of the largest terrestrial mammals that has ever existed and lived from the Early to Late Oligocene epoch (34–23 million years ago). The first fossils were discovered in what is now Pakistan, and remains have been found across Eurasia between China and the Balkans. Paraceratherium means "near the hornless beast", in reference to Aceratherium, the genus in which the type species P. bugtiense was originally placed.
Art credit goes to agustindiazart
Sanciusart, MrBlueShark, brianj996b and SameerPrehistorica
Artist note:
A selection of pterodactyloid pterosaurs known as pterodontians, to scale.
Ask the average person to describe a pterosaur/'pterodactyl', and one can expect that Pteranodon would almost certainly fit the answer: a large flying reptile with long wings, a big head with a large backwards-pointing crest and narrow beak. Admittedly there might be some other inconsistent and incorrect features included, such as sharp teeth, a long tail and talon-like feet for lifting prey! It became the iconic pterosaur following the unearthing of fossils during the late 19th century Cope/Marsh 'Bone Wars'. Pteranodon was impressively large (up to 7 metre wingspan) and had a unique appearance, so it wasn't surprising that it became the mainstay in many prehistoric illustrations, soaring over the heads of ground-dwelling dinosaurs, even if placed in the wrong location and time. However it was not ubiquitous, being restricted to Late Cretaceous deposits in North America and tied to the inland seaway. The behaviour of Pteranodon and their closest relatives was like modern albatrosses, living much of their lives at sea using dynamic soaring to efficiently cover long distances while foraging. Like other pterosaurs, they launched into the air from a quadrupedal stance, generating thrust from the powerful forelimbs. It seems likely that Pteranodon was also able to do from the water's surface, and also dive deeply underwater to catch prey.
The most distinctive feature of Pteranodon is the long crest at the back of the skull. Initially it was assumed that the crest was an aerodynamic counterbalance to the long beak, however other long-skulled pterosaurs (azhdarchids, anhanguerids, ctenochasmatids) lacked a similar counterbalance. Other suggestions that it acted as a brake or for heat exchange are similarly been dismissed. Head crest shape varies widely between specimens, such that multiple species of Pteranodon have been named. While two species (longiceps and sternbergi) are considered valid, the shorter triangular crest prevalent in smaller individuals actually represents females. Crest shape and skull material is unknown in other pteranodontid species.
Even more specialised and extravagant were the head crests of the closely related nyctosaurids. Not all individuals of Nyctosaurus bear crests (indicating immatures and females, or damage), several fossils display very large distinctive antler-like crests which can reach 55 cms tall. Initially it was thought that a headsail stretched between the two spars of the crest, however the rounded edge of the bone lacked any attachment points. In comparison the Muzquizopteryx had a short rounded crest at the rear of the skull. Nyctosaurids also uniquely lack the three small clawed fingers on the hand which are present in all other pterosaurs. It is probable that they spent relatively little time on land, and were generally pelagic soarers.
Pterandontian pterosaurs survived right up to the K-Pg extinction event.
Artist note:
A slighty belated render of the Newly described, beautiful and unusual Triassic reptile Mirasaura grauvogeli from the Middle Triassic of France.
Mirasaura is distinctive for an unusual sail of elongate feather-like structures, a feature only seen before in the enigmatic and closely related Longisquama of Kyrgyzstan.
The superb preservation of Mirasaura, including these striking soft tissue structures and a near complete skull have helped solved a phylogenetic mystery by determining it an the previously untraceable Longisquama as primitive offshoot of the drepanosaurs, an equally strange group of Arboreal Triassic reptiles, known for their chimeric mix of bird-like skulls giant hand claws, unusual arm bones, humped backs, and strange hook-tipped prehensile tails.
Art credit goes to ValkkArt
Artist note:
The main head differences between both species of Spinosaurus
Artist note:
A Smilesaurus relaxes in the shade of a Glossopteris tree and a Cistecephalus comes out of its burrow.
This image was a private commission. I do not own this image and can not give consent to anyone wanting to use it, so contact me if you do want to use it! The image was uploaded only with the buyer's consent.
The scene takes place during the Late Permian in South Africa, around 255 million years ago.
Smilesaurus was a large gorgonopsian, a group of carnivorous therapsids, and had a skull length of around 31 cm (1 ft). Its most notable feature are the very long canine teeth, which remind of saber-toothed cats.
In this painting, I also tried to depict the parietal eye and the reflected lamina of the angular bone, two very interesting structures that I won't explain in detail here.
Glossopteris trees were very common during the Late Permian in the southern regions of Pangaea. They probably were deciduous, since their long, tongue-shaped leaves have often been found in dense accumulations.
Cistecephalus was a dycinodont therapsid that was likely a burrower. It dominated the fauna in the Cistecephalus Asselmblage Zone, part of the Karoo Supergroup.
Digital painting by Peter Nickolaus, 2026.
Artist note:
In the early Permian, a little less than 300 million years ago, life on land was rich and diverse, but most of the animals were still a bit... goofy.
This is a scene from the ecosystem preserved in the Texas Red Beds, where early relatives of today's amphibians, reptiles and mammals all still looked more or less like heavily built lizards. Eryops, a large predatory temnospondyl, is chasing down one of its smaller relatives, a Platyhystrix. The commotion has startled some large palaeodictyopterans, winged insects not closely related to anything living today. You can also find a couple of cockroaches and millipedes, not much changed since, and a bird-sized griffinfly in a background.
The area was mostly quite arid, but crisscrossed by many rivers. Along the rivers it was probably more humid and green, much like you can still see where rivers flow through deserts. The dry leaves on the ground are drawn after actual species known from fossils, but the little epiphytic ferns and fungi are mostly hypothetical.