Nix Illustration – Paleontology and science illustration

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Hello there!

Welcome to the ~~long-overdue~~ new version of Nix Illustration!

Pardon our dust – we’re still working on getting everything properly set up here, and also gradually importing in multiple years’ worth of archived content from tumblr.

Please note that unless otherwise stated, all original non-commissioned work here is published here under a Creative Commons Attribution-NonCommercial license (CC BY-NC 4.0) – you are welcome to use images for non-profit , educational, or personal purposes, provided you credit me and give proper attribution.

Please contact via email (mail@nixillustration.com) to inquire about commercial image licensing or custom commission work.

In the meantime, you can find more complete selections of work at any of these places:
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Current archive status:
–posts from pre-2018 still in progress

Postschizotherium

Postschizotherium intermedium was a large hyrax that lived during the late Pliocene and early Pleistocene, about 2.5-2.2 million years ago, in what is now northern China.

About 1.5m long (~5′), it had very high-set and sideways projecting eye sockets similar to those of modern hippos, indicating it probably had a similar sort of semi-aquatic lifestyle. The shape of its skull also suggests it may have had a short tapir-like trunk.

Much like modern hippos or capybaras Postschizotherium probably spent much of its time wallowing in bodies of water, and emerging onto land to graze on grasses. Its habitat would have been humid forest and grasslands, alongside other animals such as large horses and bovines, one of the last chalicotheres, woolly rhinos, beavers, macaques, bears, big cats, early lynxes, and scimitar-toothed cats.

Ubaghsicystis

Ubaghsicystis segurae was an echinoderm that lived during the mid Cambrian, about 506-497 million years ago, in what is now Spain. Similar fossils are also known from Morocco, Mexico and Canada, suggesting this genus was quite widespread in marine continental shelf habitats at the time.

It was part of an extinct group known as eocrinoids, which were the earliest known echinoderms to develop stalked bodies and specialized feeding appendages — but despite the name and similar body plan, their resemblance to crinoids was due to convergent evolution rather than any direct relation.

Its globular body was only about 5mm in diameter (~0.2″), with a long stalk at least twice that length ending in a small disc that attached it to the substrate. The upper half of its body was dotted with small holes (called epispires) that probably served a respiratory function, and unlike most other eocrinoids it seems to have had just two slender flexible feeding appendages.

It would have been a suspension feeder, using tube feet to catch food particles floating around in the water, then move it down to its mouth positioned at the base of the two “arms”.

Luoxiongichthys

Luoxiongichthys hyperdorsalis was an early ginglymodian ray-finned fish, related to the ancestors of modern gars, living during the Middle Triassic (~244 million years ago) in coastal tropical marine waters covering what is now southwestern China.

About 15cm long (~6″), it had a large hump on its back shaped like a backwards shark fin. Its deep body was wider at the base, giving it a triangular shape when viewed from the front similar to some modern tropical fish – and suggesting it may have had a similar sort of ecology as a slow but highly maneuverable swimmer feeding on small seabed invertebrates.

Austriadactylus

Austriadactylus cristatus was an early pterosaur that lived during the Late Triassic, about 215 million years ago, in what is now Austria and Italy.

It’s one of the most basal (“primitive”) pterosaurs currently known, with its long tail lacking the stiffening bony rods seen in other early “rhamphorhynchoid-grade” forms.

It had a wingspan of around 1.2m (~2′), and a bony crest on its snout that grew taller towards the front. Its jaws contained a mix of two different tooth types – a few long pointed teeth and numerous smaller three-pointed teeth – with wear patterns that suggest its diet primarily consisted of hard-shelled invertebrates.

Megabalaena

Megabalaena sapporoensis was a member of the balaenid baleen whale lineage, related to modern right whales and bowhead whales. Living in marine waters covering what is now northern Japan during the late Miocene, about 9 million years ago, it helps to fill in a significant gap in the fossil record of this group.

Known from a partial skeleton about 12.7m long (~42′), it was much larger than earlier balaenids, but smaller than modern forms. It also had a narrower flipper shape compared to its modern relatives, a less arched jaw, and its neck vertebrae were only partially fused.

Modern right whales are slow-swimming ram feeders, but since Megabalaena was less specialized for this particular filter feeding style it’s unclear what its ecology was.

Dimacrodon

Dimacrodon hottoni was a synapsid that lived during the mid-Permian, about 272 million years ago, in what is now Texas, USA.

Known only from incomplete skull material, it had a thin bony crest on its forehead and a long snout with unusually toothless jaw tips — which had a rough bone texture suggesting there was a small keratinous beak there.

Its full body proportions aren’t known, but since its skull measured around 50cm (~1’8″) it was probably at least 2.5-3m long (~8-10′).

When its fossil remains were first discovered in the mid-20^th century it was thought to be a dicynodont-like anomodont, but later examination in the 1990s suggested it was actually a more basal “pelycosaur-grade” synapsid, possibly a sphenacodont close to early therapsids. There hasn’t been any further study on Dimacrodon since then, though, so its exact evolutionary relationships remain very murky.

Its ecology is equally unclear, but its beak-like jaws suggest it may have been somewhat herbivorous. It would have lived around a coastal river delta in a semi-arid climate, alongside herbivorous caseids like Cotylorhynchus and Angelosaurus, predatory sphenacodontids like Dimetrodon, small lizard-like parareptiles and captorhinids, and aquatic temnospondyl amphibians.

Xiphodracon

Xiphodracon goldencapensis was an ichthyosaur that lived in marine waters covering what is now the Jurassic Coast of the southern United Kingdom during the Early Jurassic, about 188 million years ago.

Around 3m long (~10′), it had fairly large eyes and a long narrow snout lined with small slender pointed teeth.

It was part of the leptonectid family, closely related to other long-snouted forms like Eurhinosaurus. Although currently only represented by a single fossil specimen, it’s actually the most complete ichthyosaur known from the Pliensbachian age of the Early Jurassic.

Preserved gut contents show that it primarily fed on fish, and also that its stomach was positioned on the left side of its body. The fossilized individual also suffered from multiple injuries during its life, including malformed teeth, a fractured clavicle, and avascular necrosis in its upper limb bones. It appears to have died after a bite to the skull from a predator – likely the larger ichthyosaur Temnodontosaurus – and additional bite marks on one hindlimb may be evidence of scavenger activity.

Spectember/Spectober 2025 #08: Alphabugs

One last entry for this year!

Dwoll suggested “a family of creatures that have evolved to look like every letter of the Roman/English alphabet”:

A digital sketch of a speculative treehopper bug. It has a large elaborate "helmet" crest on the back of its neck forming a shape that resembles the letter A.

Grafficimex dwolli is a domesticated species of treehopper closely related to the neotropical genus Cladonota.

Its wild ancestor, the now-extinct species Grafficimex ignotus, had an elaborate pronotum “helmet” with a close resemblance to the English letter F. It proved to be surprisingly easy to raise in captivity, being docile around humans and happily using common houseplants such as Monstera as hosts, and it was also quite morphologically variable. Varieties resembling letters such as E, C, and U were quickly developed, and hobbyists began competing to breed more and more new shapes.

Now, after centuries of selective breeding, the English alphabet has been completed, along with a couple of recently-developed breeds with bulbous protrusions that resemble question mark and exclamation mark shapes.

An "alphabet" of speculative Grafficimex treehoppers with crests that resemble the letters from A to Z, along with a pair that resemble a question mark and an exclamation mark.

(Breeds resembling the alphabets of other languages are also in development.)

At about 2cm long (~0.8″), Grafficimex dwolli is rather large for a treehopper, and much like the domestic silk moth it has almost entirely lost the ability to fly.

Along with being kept as novelty pets, often carefully lined up on plant stems to spell out amusing messages, these insects are also quite popular with beekeepers – the honeydew produced by Grafficimex nymphs and adults can be harvested by bees to make dark strong-flavored honeydew honey.

Spectember/Spectober 2025 #07: Kelp Yourself

An anonymous submission asked for a “live bearing bird”:

A digital sketch of a speculative aquatic descendant of moa birds, shown swimming in a kelp forest. It has a small head with a turtle-like beak, a long neck, no wings at all, a streamlined body, and large flipper-like webbed feet. Clumps of long ribbon-like feathers run down its back, vaguely mimicking the appearing of kelp fronds.

Rimurimuornis ovovivipara is a future descendant of the broad-billed moa, in a timeline where these Aotearoan birds weren’t hunted to extinction.

About 2m long (~6’6″), this fully aquatic bird grazes in kelp forests and seagrass meadows. It’s a rather slow swimmer, propelled solely by its large flipper-like feet – because like all moa it completely lacks wings.

Its ancestors’ laid incredibly thin-shelled eggs, and a combination of reducing the hard shell away even further to a more leathery state, then increasing egg retention time inside females’ bodies, has led to this lineage evolving an ovoviviparous form of live birth at sea.

It also has long ribbon-like feathers along its back that mimic the appearance of seaweed fronds. While terrestrial moa have few large predators to worry about, Rimurimuornis has to contend with sharks, orca-like whales, and leopard seal-like pinnipeds, and if its camouflage fails its primary tactic to discourage attacks is defensive defecation.

Spectember/Spectober 2025 #06: A Curiously Charged Choristodere

The Dark Master requested: “Maybe a speculative Placodont or choristoderes. Feel free to do anything, just if they had continued to evolve and survive”

A digital sketch of a speculative descendant of choristodere reptiles. It's an aquatic lizard-like animal with a wide flat head with long narrow jaws, a long neck, four webbed paddle-like limbs, and a long eel-like tail.

In a slightly different timeline to our own, the last surviving choristodere Lazarussuchus didn’t go extinct during the Miocene. Instead it survived in European waterways until the Messinian salinity crisis, and dispersed down into northern Africa when the Strait of Gibraltar closed up.

During one of the “Green Sahara” humid periods its descendants made their way further south, and now Keravnodraco dominusobscuri is found in lakes and rivers throughout the rainforests of West and Central Africa.

About 1m long (3’3″), it hunts small fish and aquatic invertebrates in dark murky waters, using a unique set of electrogenic organs in its elongated neck to actively sense the bioelectric fields of prey in dark murky waters – and also generating electric shocks that can stun its targets or deter predators.