Collared Ritsuara + Brown Ebusoir

One day, while out on a sailing trip, one of our research vessels conducting a regular assignment in the southern Riatis Ocean by the Baracenian coast in north Guralta picked up on a lot of commotion happening below the waves.

Their sonars detected a lot of vibrations that sounded like clicks and chirps, as well as growls, wails and even "roars". 

This was not the first time we would have found a baitball event due to the commotion underwater, but this was different.

There were no aerial predators and scavengers around as one would expect during a baitball. Instead, what they saw when they send submersibles underwater was far more horrifying.

They saw an adult Brown Ebusoir (Syntrivodon fuscus), a large durophagous marine Arachnothere, being assaulted by a gang of Collared Ritsuara's (Fermourodus collaris).

No one had ever seen Ritsuara's gang up on a much larger creature like this before. But they were not just harassing it, they were hunting. While we were aware that this particular species of Fermourodontid had more triangular and slightly more serrated teeth than most others in the genus Fermourodus, we did not know what they used these for.

But now it became clear.

While other Ritsuara's use their three jawed mouths and seven rows of teeth to chop smaller prey like a guillotine, something Collared Ritsuara's undoubtedly do as well, these Fermourodonts use their more triangular teeth to inflict lacerating wounds on larger prey items.

They do not hunt with just brute force, but rather they aim to weaken their prey and bleed them out to the point where they can no longer fight.

At up to six meters long however, a Brown Ebusoir is no easy pickings. These massive marine Arachnotheres possess eight strong flippers that can easily cause a concussion and have insanely strong jaws lined with rows of teeth designed for crushing the shells of huge sedentary bivalves and large Pectinauts. One well placed bite from an Ebusoir could crush a Ritsuara into a bloody pulp.

Malar-striped Ritsuara

It is no secret that the oceans of Eryobis are filled to the brim with life. You do not have to go far to encounter a marine creature in one way or another.

There are however some animals that prefer to avoid us. Fermourodonts are one such case. 

Their electric senses make have caused them to develop a resentment towards anything man-made with an even remotely detectable electronic signature. Their excellent sense of smell also allows them to distance themselves from us without us ever even knowing they were there.

Because of this, our understanding of how Fermourodonts live is quite limited, but occasionally we get treated with a surprise.

One such surprise was when one of our ROV's was observing a shoal of squidn't like nienktvissen of a yet undetermined species, when a Malar-striped Ritsuara (Fermourodus balatrius) came up from the depth with great speed.

It seems to have used the distraction our ROV caused to perform an ambush on the nienktvissen and provided us with the first time we could witness their hunting methods up close.

Quite brutally, the Ritsuara used its three jawed mouth and seven rows of sharp, blade like teeth to literally slice the nienktvissen in half. Upon closer inspection of the footage, it became clear that the visendal rows on the mandibles and the central row of teeth on the trapezium were larger than the other teeth. When Ritsuara's close their jaws, they essentially become guillotines.

Malar-striped Ritsuara's seem to average at around three meters long, not too large, but definitely big enough to cause some serious harm.

Cladistics: Oxysalpincoidea

Oxysalpincidia are the most widespread Diplaulote Trapezostomes on Eryobis and include a myriad of families and species.

But perhaps the most recognizable members belong to a subdivision of the group, the superfamily called Oxysalpincoidea.

Members of this subfamily are more bipedal than their relatives and the majority of their kind are completely bipedal with greatly reduced front limbs.

While Oxysalpincoids likely came from the continent of Tlèëa, these bidepal forms seem have had their origin in Guralta. These creatures are almost exclusively herbivorous and occasionally enrich their diet with arthropods and other invertebrates like fallen skysquirts. 

Some of the most commonly encountered Oxysalpincoids are the Tachyornithids. These highly cursorial herbivores can often be seen roaming the savannas and plains of Guralta and southern Tlèëa in huge flocks. They are known for their short faces and beaks, extremely short arms with clawless rudimentary digits. In the males, these arms are often brightly colored and only serve for sexual display. 

Additionally, Tachyornithids often have elaborate headgear and spiracular tubes and that are usually just as brightly colored as the arms in males. 

Compared to these slender athletes, their closest relatives are completely on the other side of the spectrum. The Behemopods, while equally bipedal as Tachyornithids, went in the other direction and instead of becoming long legged runners, became massive tanks. 

Behemopods dubbled down even more on reducing their arms to the point where they get fused into the skin. But since running no longer became a viable option as they grew in stature, they needed some kind of defense. So these titans derived what they still had to an extreme extent. In a very Kadrian way, they turned the claws from their arms into massive spikes for self defense. These fearsome claws, combined with their strong scaly and often armored tails and immense sizes make Behemopods a force to be reconed with.

The majority of their kind are at least 8 meters long from head to tail, with the very largest species having been recorded at over 21 meters in length. This makes Behemopods the biggest animals in Guralta, some of the largest terrestrial animals alive and by far the greatest land based Trapezostomes to have ever lived.

There's also the basal genus Xenulops, which is kind of an enigma. It lives in the dense forests of Lachoba, far more southern than other Oxysalpincoids. 

Any DNA tests on it have come back inconclusive, with some placing closer to Tachyornithids while others place it closer to Behemopods and then there are a few that suggests its more basal than either.

Unlike either other family, Xenulops retains its arms with all of its digits and claws intact. Its feet are similar to those of Behemopods while its overall leg anatomy is more akin to Tachyornithids. It is an odd genus that is likely to continue being enigmatic for the foreseeable future.

Mantleback Ritsuara

When you dive into the Voûlic Ocean in the south of Eryobis, there is a good chance you will encounter wildlife in one form or another. 

This south polar ocean has some of the most nutrient rich waters in all of Eryobis and thus is booming with sealife.

One of the most common large animals you can encounter here is the Mantleback Ritsuara (Tristinectes amictus). This medium sized Fermourodontid averages around 3.5 meters in length and is an avid piscivore. 

Its seven rows of small needle like teeth are perfectly suited for catching slippery prey like fish, smaller conodonts and llamplelgans. 

They can often be seen traveling in small pods of related individuals and tend to be found a couple kilometers from shore, although they do sometimes come closer to the coast to hunt or birth.

This species of Ritsuara is one of the friendlier ones we've encountered so far. Like all Fermourodonts, they have an electromagnetic field around their mouths, electric whiskers if you will. Because of this, they tend not to respond all too well to our mechanical equipment.

Mantlebacks, thankfully, will not go out of their way to attack and destroy said equipment...unlike some other species. 

Because of this, we do get a fair amount of opportunities to see them in the wild if we go in the water with just traditional equipment that doesn't really have an electrical signal.

Cladistics: Trapezostomata

Modern Anisospondyls can be placed into one of three major categories. There are the Brachiostomata, a group which was apparently very diverse in Eryobis' her past but is now only represented by a handful of species. There are the Cryptognatha, the Anisospondyls that evolved a second set of jaws derived from their palates and tongue bones and the group that by far the most modern Anispondyls fall into.

And then there the Trapezostomata. These creatures are most easily recognized by a feature seen in no other Anisospondyl living or dead: an elongated bony plate below the mouth called the trapezium. 

It is theorized that they evolved this feature to combat the ever existing issue caused by having horizontally opening mouths, food falling out. The trapezium prevents this. To accompany this, many Trapezesotomes also have fleshly, often muscular lips and cheeks.

Trapezostomes are likely just as old as, if not even older of a clade than the Cryptognaths. Genetic evidence suggests that the two lineages had already split around 160 million years ago in the Swifterbantian stage of the Bobossic period. The two main branches, as well as likely a few more, of Trapezostomata were already well established by the Jerounian and Kikilian stages, as is shown by a rather derived member of Liomedactylomorpha having been found in the Reinaut Formation dated to the end of the Bobossic.

In modern times, we can place Trapezostomes into one of two groups, the Liomedactylomorpha and the Strotopalates. The molecular clock suggests these groups differentiated between 145 and 130 million years ago and thus must have survived the cataclysm known as the World Scarring at the end of the Bobossic independently. 

Of these two groups, the Strotopalates are typically regarded as the more primitive of the two. 

Strotopalates are most easily distinguishable by their jaw anatomy. The seem to have lost their palatine teeth very early in their history and evolved to have a completely closed palate that bears a striking resemblance to those of placental mammals. Their dentary likewise has also been sealed off. This likely evolved to grant early Strotopalates a stronger bite.

Their land based representatives are relatively few in number and are reptilian in appearance, usually being scaly and ectothermic. The most basal members, the Tardosaurids, are medium sized slow moving herbivores that inhabit a number of small islands in the central and southern regions of Rubiëra. The Novalacertoids are bit more diverse and widespread, being found in virtually every corner of the Rubiëran archipelago. They are usually small with very elongated, almost serpentine bodies, consequently they mostly feed on burrowing arthropods and annelids. 

The Hastamentids are perhaps some of the most recognizable Trapezostomes alive. Some of their species can stand up to 1.5 meters at the shoulder and all can be quickly recognized by the long spear like trapezium sticking out far beyond their jaws. This peculiar trapezium is, quite obviously, used to spear prey. Most Hastamentids are semi-aquatic and often hunt by standing by the waters edge and impale aquatic prey that comes to close.

Their visendal arms are permanently held off the ground and are mainly used to manipulate food speared up on their trapezium.

But there is another superfamily that belongs to Strotopalates that strayed quite far from their other kin. These are the Fermourodonts, fully marine creatures that are neither scaly nor ectothermic like other Strotopalates. One of their most defining traits are their jaws and skulls. Anisospondyl skulls in general are odd looking and appear twisted and disfigured compared to Tetrapod and Arachnopod skulls, but Fermourodonts take this a step further. Their caecal spircales have migrated to the visendal side and as a result warped the entire skull. Fermourodonts thus possess the unique ability to open their jaws at wide and odd angles that, in combination with the trapezium, results in them having a three part jaw. This allows them to chop and slice their prey in ways that no other animal can.

It is unclear where Fermourdonts came from since they have no close terrestrial relatives anywhere. Because of this, there are some that suggest Fermourodonts might have evolved somewhere other than Rubiëra, where all other Strotopalates can be found, but until some fossils are discovered, we cannot know. In modern times, we see two distinct kinds of Fermourodonts, the Palaionychids that somewhat resemble the prehistoric Metriorhynchids of Earth and the Fermourodontoids, the infamous "zipper dolphins" or ritsuara's of Eryobis. 

Both of these groups are fully aquatic, although Palaionychids still do possess some functional digits and claws, these are mainly used to help them navigate through reefs, crevices and vegetation. Another unique trait that all Fermourodonts possess is what can best be described as "electrical whiskers". Their jaws are covered in rows small of electric organs that create a small electromagnetic field around the snout. This allows them to perceive living things without needing to see them. This adaptation is also a reason why Fermourodonts seem to despite humans. Our electrical equipment and ROVs seem to agitate them to the point where some will actively attack and destroy our devices whenever they encounter us. 

It is a shame really, because Fermourodonts have proven to be among the most intelligent creatures on Eryobis, yet we evidently cannot examine them up close in their natural habitat.

Liomedactylomorpha are regarded as more advanved compared to Strotopalates. One of the reasons for this is the fact that Liomedactylomorphs symmetrized the toes on their front limbs. While several other groups like Eusymmetrodactyl and Parasymmetrodactyl also symmetrized their toes by reducing a toe of their lacrimal limbs, Liomedactylomorphs instead fused the 3rd and 4th digits into one.

Another is the removal of the ancestral "fish nostrils" from the jaws and having those be replaced by new olfactory organs derived from glands near their eyes. These drape down from the eyes and end around the corner of the mouth between the mandibles and the trapezium.

Without the exception of the Trapezosauridae, all Liomedactylomorphs fall into Liomedactylae. Likewise, all except the former all endothermic creatures possess some kind of fur covering. Liomedactyls possess prominent spiracle structures made out of bony rings and cartilage. These resemble the spiracle structures of Eusymmetrodactyls in the fact that they are also covered in hard keratin, but unlike those, the spiracle structures of Liomedactyls split into two separate tubes akin to the fleshy spiracle structures of some Effingodactyls. 

Uniquely, Liomedactyls have evolved to use these largely hollow tubes to detect sound and as such, usually have several disc like shaped and pressure points spread over their headgear.

The most basal members, the Trochotheroids, are Mustelid like omnivores that typically have long bodies with relatively short legs. 

Triprotodontia

Other Liomedactyls seem to be largely divisible into three major lineages.

The first of these is the branch that leads up to the Triprotodontia. All members of this branch can be identified by the orientation of their toes on the hind legs, with the first, second and third digits being mainly used for walking while the fourth and fifth digits are reduced and often vestigial. Odd looking creatures like herbivorous Kormerpetontids and the rat/ shrew like Projunctinariids belong at the base of this branch. 

The latter represent a transitional form between more basal Liomedactyls and the advanced Triprotodonts. These have a number of unique features, like their spiracular structures that feature large auricule spheres at the back of the head and tube openings that always face out- or backwards. They also possess the ability to open their jaws at an odd angle, giving them an almost three part jaw, although it is nowhere near as developed as those seen in Fermourodonts. 

But perhaps the most unique feature of Triprotodonts is the fact that they have fused their caecal spiracle opening with their olfactory organs and moved this newly evolved "nose" to the very front of the trapezium. This makes them look as if they have an inverted mammal snout and is an adaptation seen in no other group of Anisospondyls.

Triprotodonts are the most successful and widespread clade of non-flighted terrestrial Anisospondyls ever. These rodent like creatues are present on every major landmass except the continent of Hatèmica and often dominate the niches of small sized herbi- and omnivores. They are divided into three groups mostly based on where they can be found.

On the continents of Tlèëa, Guralta and Lachoba, we can find the Boreoglires that were named because they took the northern route to spread across the continents.

The other two groups are generally considered to be more closely related to each other than either is to Boreoglires. The Rubioglires are the group of Triprotodonts that mostly restricted to the Rubiëran archipelago, while the Austroglires are almost exclusively found on the continent of Miesjeta.

Diplaulotes

Besides the Triprotodontia, there are two other, often more noticeable lineages of Liomedactyls.

Both of these have features that easily set them apart from any other Anisospondyl family dead or alive.

The clade known as the Diplaulotes possess some of the most charismatic headgear of any animal on Eryobis. At some point in their evolution, a mutation occurred that caused them to grow a spiracular structure not just on the visendal spiracle, but on the caecal side as well, giving them their iconic quadruple tubed look.

The most basal Diplaulotes are the Tetramyteiids, a family of civet like creatures that are quite similar to the Trochotheroids in appearance and lifestyle.

The other Diplaulote groups are united by a few characteristics in their foot anatomy such as the sideways orientation of their hands on their front feet and the loss of the fifth digit on the hind-limbs. 

While nearly all members of this group are devoted herbivores and occasional omnivores, they do contain one family of hypercarnivores, the Machairoplatids. These feline looking predators have evolved a large sharp spike on the edge of their trapezium which they use to kill, much like the saberteeth of various prehistoric carnivores from Earth. Machairoplatids always hold their caecal limbs, which are set further towards the middle than the visendal limbs, permanently off the ground. These free arms have opposable fingers that sport large claws for restraining prey before they can deploy their sabers as well as for carrying their offspring.

The other "higher" Diplaulotes are nearly all herbivores. Some of these, like the Grothiacheirids have evolved one pair of their front limbs into club like appendages. These are made out of their modified foot bones and are lined by their stud like hooves.

The Liotelares are typically more stocky in build that other Diplaulotes and have shorter tails. These creatures can best be recognized by their tubes that have fused together and meet in the middle of the head.

The Oxysalpincidia are the most widespread of the Diplaulotes and contain a myriad of species ranging from small and slender hexapods to titanic bipedal behemoths. Indeed, some of the largest terrestrial animals alive and consequently, the largest terrestrial Trapezostomes to ever exist are Oxysalpincidians.

Exolophodontia

The final of the three major branches of Liomedactylae are the Exolophodontia. These creatures are perhaps the most un-Trapezostome like Trapezostomes ever. In fact, for the first decade or so after explorations on Eryobis began, the Exolophodonts were not even considered to be Trapezostomes because they often have strongly reduced- or completely lack trapeziums. 

Exolophodonts gain their name from their teeth which are, peculiar to say the least.

Liomedactyls all started out with a full set of teeth on their maxilla, dentary and a row of palatine teeth. At some point in their evolution, the ancestors of Exolophodonts suffered a mutation that caused their maxillary teeth to turn outwards and would end up forming a "crest" of teeth that stuck out of the mouth.

For most Anisospondyls this would be disadvantageous in several ways, but since these Liomedactyls still had fully functional palatine teeth, they were able to compensate.

It is likely that individuals with these odd teeth were selected for because it likely showed their fitness and ability to live with a feature that would seem like a hindrance. Soon these teeth would be developed into all kinds of shapes and sizes. 

Some of the most basal Exolophodonts are the Ankylotalariidae, a family of arboreal omnivores with strangely shaped ankle bones and prehensile tails. Typical of many basal Exolophodonts, their toothy crests give their face an appearance akin to a leiomano or macuahuitl. Despite this seemingly fearsome look, the teeth are brittle and are exclusively meant for display.

The Choeromelidae are another quite basal family of Exolophodonts, although these creatures have more specialized maxillary teeth than other basal members. The tusks of Choeromelids are strong and are used for digging up food, scratching the bark of trees and for combat. Curisouly, these critters have some of the most well retained trapeziums of any Exolophodontian family.

The family that the order derives it name from, the Exolophodontidae, are a family of medium to very large sized herbivores native to the Rubiëran archipelago. These pachyderms have spade like crest teeth that are often larger on the visendal side than on the caecal side. They are the largest land animals in Rubiëra and they permanently hold their caecal limbs off the ground. These are used for digging, collecting food and fighting.

In a curious case of convergent evolution, a family of Exolophodonts evolved a very similar body shape and lifestyle to the Cryptognaths known as Kadrians. The aptly named Pseudokadridae are also a family of long, slender legged herbivores that, like their namesakes, walk quadrupedally while having reduced one pair of their front limbs. Unlike actual Kadrians whose non walking front limbs have turned into defensive weaponry, the Pseudokadrids use theirs to hold and transport food, other materials and offspring. The tooth crests of Pseuodkadrians can vary wildly between different genera and even species, but they are generally quite sturdy and are often used for both intraspecific combat and defense if necessary. Their spiracular tubes are also often quite elaborate and brightly colored, especially in the males and are mostly used for display.

Pseudokadrids are also one of the very few members of a group called the Choritrapezioidea that are found outside the continent of Miesjeta. Most other members of this group can be in Miesjeta, with the subcontinent called Lotharca being especially rich in their diversity.

One of the most charismatic families of this group are the carnivorous Hemerosmilids. These predators are best known for having reduced all their maxillary teeth except for one, which they turned into a large blade shaped tusk with serrated edges. With this, they are the second family of Liomedactyls to evolve into sabertoothed carnivores along side the Diplaulote Machairoplatids. They are not closely related at all however and evolved on opposite sides of the world. Hemerosmilids are also known for their peculiarly shaped headgear that often resemble caricatured wings. Because of this, some explorers call them "cats of Hermes". 

Perhaps the most widespread family of Choritrapeziods are the Polemotheriidae. These squat, pig to rhino sized herbivores can be found all over Miesjeta as well as some islands surrounding the continent. Like the Hemerosmilids, these creatures have also greatly reduced their number of maxillary teeth in favor of a few, but very large tusks. These are used for all kinds of daily activities like digging, stripping vegetation, combat and breaking through ice.

When one observes the locations of where terrestrial Trapezostomes can found in Eryobis, it becomes noticeable how the majority of their more basal taxa can be found in Rubiëra. 

Rubiëra ofcourse, is a massive archipelago that consists of the remnants of highlands of a sunken continent that was once much larger. Based on its unique flora and fauna, researchers think that Rubiëra has been more or less isolated from the rest of Eryobis since the World Scarring occurred. 

Because of this Trapezostomes were able to evolve and diversify unhindered by the Cryptognaths that dominated all other continents. 

Back in the early Afthonozoic, Rubiëra as well as Lotharca and Augadrië and possibly parts of Wyndraë were united in a much larger continent dubbed Magna-Rubiëra. It is likely that Liomedactyls used the breaking up of this paleocontinent to spread across the world. 

Exolophodonts and Austroglires hitched a ride on Lotharca to spread to the rest of Miesjeta and the Diplaulotes seem to have evolved in Augadrian Tlèëa after the breakup of Magna-Rubiëra. Boreoglires likewise used Augadrië and Wyndraë to spread to the rest of Tlèëa, Guralta and Lachoba.

Currently, the only continent without any terrestrial Trapezostomes is Hatèmica. This continent was likely already isolated from all others by the time Liomedactyls spread out from Rubiëra.

Hatèmica however seems to be on a collision course with Guralta, is moving exceptionally fast for a continent and is likely to make contact within the next 20 milion years. So its apparent lack of Trapezostomes is destined to come to an end.

Cladistics: Monotoalosia (Kadriomorpha)

Among modern Anisospondyls, there are few as diverse as the Eusymmetrodactyla. The bulk of their species and diversity comes from their flying members, the Stauropterygians, which were obviously able to disperse and diversify around the globe quite easily.

But the second most successful group of Eusymmetrodactyls is nothing to scoff at either. 

The Monotoalosia are often considered to be the dominant macrofaunal herbivores of Eryobis. They can be found on every major landmass except Rubiëra and are usually counted among the megafauna wherever they exist.

The Monotoalosia are a rather odd looking group, even for Eryobian standards, and have an interesting but unexpected evolutionary past. Genetic testing and paleontological evidence suggests they split off from other Eusymmetrodactyls shortly after the Stauroptergyians split off, possibly placing their origin as early as the start of the Recrescian, some 106 million years ago. Their earliest and most basal members seem to have been small, gliding, rodent like animals and curiously, one family of these most basal members survived to modern times in the tropical rainforests of Bloëca, the Paleovolyidae.

The revelation of Paleovolyids as Monotoalosians was a quite recent one. It was previously assumed that they were members of Polyotoalosia that simply had only one pair of auricular filaments and a beak at the end of their mandibles. But a reexamination of their foot anatomy, in which their front feet are oriented "sideways", and some molecular testing revealed that they were in fact closer related to Kadriomorpha than to any other Eusymmetrodactyls. 

It would be this discovery that led to the answer of a question that scientists had been asking since the very beginning of Eryobian exploration: how did Kadriomorphs get those odd traits?

Indeed, Kadriomorpha are ranked among the strangest looking of Anisospondyls. But not for their alien looks, no rather for the fact that they don't look like aliens. Their appearance has a lot of similarities with hoofed animals from Earth and like them, Kadriomorphs are almost all completely quadrupedal with heavily reduced visendal front limbs. Often all that remains of their former front limbs is a long spike like claw, sprouting from their shoulders.

No one could figure out why until Paleovolyids were revealed as their cousins and the group Monotoalosia was officially created. The Kadriomorphs inherited their traits from ancestors that were specialized in gliding.

It is speculated that Kadriomorphs evolved from Paleovolyid like creatures that left the trees and instead decided to make a living on the ground. They would have used their caecal front limbs and hind limbs to walk, while their visendal front limbs supported the patagium and were likely held off the ground.

Soon they would have lost the ability to climb and glide completely in favor of a terrestrial lifestyle.

Some of these early Kadriomorphs would have used their former wing arms to grab and manipulate food, eventually leading to modern creatures like the Nothrungulatids.

Others were reducing the wing arms and elongating the claws to serve as defense weaponry to attacks from above. Prokadrians and Bounindriids are leftovers from this stage.

As Kadriomorphs were becoming more and more adapted to a cursorial lifestyle, the visendal limbs became more reduced, their other legs become longer and stronger and their claws would become hooves. They became the Kadrians.

The Kadrians are easy to recognize. They often bear an uncanny resemblance to terran herbivores like antelopes, rhinoceroses and horses. 

The most basal Kadrians are the aptly named Protokadrids. These creatures are some of the only Kadrians alive that still walk on their toes and just their hooves and sport visendal limbs that still very much resemble hands with long claws. Some scientists doubt whether Protokadrids aren't even true Kadrians at all and not just advanced Kadriomorphs because of these primitive traits.

All other Kadrians share a number of traits that distinguish them from Protokadrids. The most noticeable of these are their completely unguligrade feet and visendal limbs that have been reduced to nothing but a single metacarpal that supports a large claw. 

Or so we thought. 

Turns out there are two families of Kadrians that do not conform to these standards. The Lagokadrids of Tlèëa have two digits and thus two claws on their visendal limbs and the Camelokadrids of western Miesjeta also still have two visendal claws and do not walk on their hooves, rather being digitigrade.

Because of this, a new group was made: the Eukadria, the true Kadrians. Besides all the aforementioned traits, Eukadrians also all share a large and well developed, chambered digestive tract that extends beyond their hips and makes the base of their tails look bulbous. In addition to their beaks, they have highly specialized linguopalatal jaws that are very long for Cryptognath standards. This second pair of jaws is able slide and can move both back-and-forth and up-and-down, making them extremely efficient in chewing tough plant matter.

The Rhamphoceratids are the most basal of the Eukadrians. In the past, this family also contained a number of gracile genera that resembled other Eukadrians more, but nowadays the Rhamphoceratids are large bulky animals that are the most massive of the living Kadrians.

Eukadria knows two major branches that are ever so slightly more related to each other than either is to the Rhamphoceratids. The less "derived" of the two are the Plesiokadria. These are typically stocky and heavy set animals with primitive hooves.

The other branch, the Neokadria, on the other hand are the more typical animals people imagine when they hear the word Kadrians. They are gracile, slender legged, often vaguely deer or antelope like animals that put all their body weight on a single hoof per leg.

Curiously, the hippopotamus like Lurdukadrids of Hatèmica have recently been proven to be more closely related to Neokadrians than to Plesiokadrians, despite bearing a greater resemblance to the latter. 

The Kadrians and Eukadria as an extension are a very old clade, which is best exemplified by their peculiar global distribution.

Back when Kadriomorphs first started appearing, the landmasses of Guralta, Lachoba, Hatèmica, Bloëca, Azchèda and western parts of Tlèëa were united in the supercontinent called Kwispuul. This may partially explain why some relatively closely related groups can be found oceans apart. 

Eukdria appear to have their origin in Guralta, which is where the Rhamphoceratids, a number of Plesiokadrians and basal Neokadrians can be found.

It seems however that some groups like the Acanthatheriids and Lurdukadrids managed to get to other continents before Kwispuul had fully broken apart.

But then there the Embolokadrids of Hatèmica and the Ceratokadria of Miesjeta. The molecular clocks of these groups suggest that they only appeared after Kwispuul was already supposed to have broken up. 

Some scientists suggest that the ancestors of these groups rafted over, but given the nature of Kadrians, that is rather unlikely. 

Most seem to believe in the theory that there must have been island chains or temporary landbridges connecting Hatèmica and Miesjeta to Guralta at some point in the past, and that these wayward Kadrians island hopped to their current locations.

In the last few years, researchers added a new and highly unexpected member to the Monotoalosia family tree: the bizarre Bouvijasiren.

This cat sized aquatic creature was for a long time, and due to a lack of proper studying, considered to be a Brachiostomatan because of its arms located below its mouth. An actual proper examination of the animal however revealed that it was not a Brachiostome at all, but rather a Cryptognath. Not just any Cryptognath too, but a relative of the Kadriomorpha whose closest living relatives appear to be the gliding Paleovolyids.

How exactly this odd critter evolved or where it came from is not yet understood, although some fragmentary fossil evidence seems to hint at it being the last relic of a once more diverse group. All that is currently known about it is that it lives exclusively in brackish and freshwater systems of the island called Bouvija and its surrounding smaller islands in the farsouthern regions of Rubiëra.

Cladistics: Arachnopoda

There are few creatures as synonymous with the name Eryobis as the Arachnopods. These aptly named eight legged terrestrial vertebrates can be found in nearly every corner of Eryobis and are perhaps even more recognizable than the Anispondyls they share the land with.

Nearly all Arachnopods share a similar basic body plan as they all have vaguely tetrapod like heads on bodies supported by eight spider like legs. But they are no tetrapods, nor are they even closely related. Matter of fact, they're not even Sarcopterygians. They are ray-finned fish of the order Holostei, which on Earth were represented by bowfin fish and gars.>

Arachnopods look rather little like their terran counterparts however, so how did they come to be?

Arachnopoda are part of the Octopodichthyes, a member of the "spiderfish" clade. It is hard to determine if spiderfish are a natural group or if its various members evolved their legs independently since we only observe one other taxon of spiderfish alive today, and those have four legs instead of eight.

Spiderfish in general often fossilize poorly, so we do not know a lot of their early history compared Planosolincolans, which tend to fossilize a lot better.

It is theorized that spiderfish evolved their legs when they separated a number of pelvic finrays from the main fin in order to prod the sediment for sustenance. This would have later led to them moving around on their free finrays until they developed into proper ossified legs. 

At some point, probably in the late Narthian period, some Octopodichthyans made their way to land and would give rise to the Arachnopods we are familiar with today.

As their legs sprouted from the pelvic girdle, Arachnopods needed to hypertrophy their hips in order to support their weight on land. Their pectoral fins on the other hand atrophied since the no longer really served a use on land. 

Many Arachnopods heavily reduced them or lost them completely, while one group known as the Osteotarida modified their pectoral fins to aid in detecting sounds, essentially turning them into ear pinnae.

Because of their massive pelvic girdles, that sometimes heavily resemble the plastrons of turtles, Arachnopods usually have rather stiff torsos. Their eight sprawling legs somewhat negate this issue however, since they provide the animals with a lot of mobility in several directions.

A rather peculiar feature of Arachnopods are their skulls. More specifically, their jaws.

Many Arachnopods have a unique jaw mechanism wherein both the maxilla, premaxilla are separated from the cranium and a dentary that is not connected to the rest of the mandible.

The maxilla is connected to the cranium with a joint that allows it to swivel and is able to slide in a groove in the mandible where a number of muscles and tendons connect to it, creating a "deadbolt mechanism" where the jaw can be locked at a certain angle.

When the maxilla swivels, it usually also causes the premaxilla and dentary to move.

We do not completely understand why this strange jaw mechanism evolved, but we do know that it adds a lot of strength to their jaws opening and closing.

Modern Arachnopods can for the most part be categorized as belonging to one of three groups: Dactylourae, Euarachnopoda and Pulvinopoda.

While the first two likely descend from a single ancestor that survived the catastrophic mass extinction known as the World Scarring, Pulvinopoda appears to have come from two distinct survivors of that cataclysm. Of these two lineages, the Neopulvinopods are the most successful and widespread while Polytryposternians are quite restricted in where they occur nowadays. Hence why Arachnopods are typically placed in one of three categories instead of four.

Pulvinopoda are considered to be the most primitive of the living Arachnopods. They are all ectothermic, often scaleless, amphibian like creatures that lack ear pinnae. Calling them basal would be an insult however. Their skull morphology is highly divergent from the earliest Arachnopods and has close to zero resemblance to those of the other Arachnopod groups.

The Dactylourae are perhaps the oddest of the Arachnopods. These almost exclusively arboreal creatures are most easily recognized by the claw at the end of their tails. While a number of basal genera still exist, most Dactylourans can be placed either within Kremasmasauria or Aioratheria. 

Kremasmasaurs are reptilian or and serpentine in appearance and often completely lack ear pinnae. 

Aioratheres are homeothermic and are typically covered in filaments, which are actually hair like keratin projections of the scales underneath.

Where the other Arachnopods ruled the land, the Dactylourans adapted by specializing in the arboreal lifestyle, being among the very few Arachnopods with an affinity for climbing.

The Euarachnopods are what most explorers first image when they hear the word Eryobis.

These Arachnopods tend to grow much larger than their other relatives, live mostly on the ground and are not dependent on close proximity to water for survival, so they are often much more easy to spot.

While basal Euarachnopods look rather similar on the outside, one can quickly determine their origin by examining their skulls. Usually, they can either be placed in Pseudozygomia or Panhesparachnes.

Both these groups have a temporal fenestra in their skull, but they evolved them independently and from different structures.

Pseudozygomians evolved a fenestra by closing a section of the oral cavity in order to create more muscle attachments and to reinforce the skull. Pseudozygomians can mostly be found in the eastern hemisphere of Eryobis, existing in parts of Tlèëa, Lotharca and Rubiëra, with the subgroup Rubiarachnes being almost exclusively restricted to Rubiëra.

Panhesparachnes evolved their fenestra by forming a bony ring to give more support to the eye and thus essentially splitting the orbit in two. Basal Panhesparachnes often don't have a completely formed fenestra, but all members of Arachnotheria do.

Arachnotheres, the famous spider beasts of Eryobis, are fully endothermic and like the Aioratheres, are covered in hair derived from thin projections on their scales.

Arachnotheres can be found on every continent except Rubiëra and possesses a great number of families, but most of them can be placed in Bloëcatheria, Kentrotaria or Hesparachnes.