Palefin Coeaai

Much like the sharks of Earth, the coeaaien of Eryobis are subject to rather simplistic names. A prime example of this is the palefin coeaai (Psittacopristis pterochrio), a species of plated coeaai (order Laminocoeaiida) that inhabits the shallow waters along the northern and western coasts of Bloëcan Miesjeta.

As is typical for coeaaien, this species also has two large pectoral fins that are permanently oriented upward to function as dual dorsal fins. While these are mostly fixed, they do possess a small degree of mobility and allow coeaaien, such as this species, a surprising amount of maneuverability and makes them able to turn on a dime. Usually slow cruisers, coeaaien can perform quick bursts of speed to catch their prey and their maneuverability and flexibility allows them to strike fast in many directions around them.

A medium sized species with an overblown ego, palefins are known to be very inquisitive and border on aggression with their tendency to bite and nip things to investigate them. Chain mail is therefore a must for divers.

While they are generally known to feed mostly on small fish and nienktvissen, their plate-like fused teeth are self sharpening and extremely durable, which also allows them to feed on tougher prey such as pectinauts. 

In addition, palefin coeaaien have been reported as avid scavengers that seem to get attracted to spilled blood in a fashion often described to sharks.

Being far from the largest coeaai species that lives around the Bloëcan coasts, they often congregate in groups of up to 30 individuals as protection. This however, also contributes to their perceived aggressive behavior, as they need to be quick and fierce in order to secure food for themselves.

Like many other members of the Laminocoeaiida, they possess a sharp spine in front of their true dorsal fin. Curiously, this spine seems to have evolved and been modified from the "spines" already present in the original first dorsal fin of the ancestral coelacanths.

Tiger Wangvin

The seas of Eryobis are full of horrors and monstrosities with faces hard to love. Evolutionary abominations like llamplelgans, creatures that look like squid-scorpion hybrids that turned out to have evolved from polychaetes, are often considered by explorers to be among the most cursed looking creatures to be found on Eryobis.

Looks are one thing, behavior is another.

Fermourodonts easily take the title of the creatures most unfriendly towards humans, given that they go out of their way to destroy our electric equipment and vehicles, while coeaaien tend to get a bad reputation because of their superficial resemblance to sharks.

There are however a few nienktvissen that also often end up high in the rankings of the most horrible creatures to be found on this world. While this is largely based on appearance, there are real life precedents of nienktvis encounters ending up lethal on our side. While this was likely an accidental anomaly that was only caused by poor handling on the explorer's part, there are other nienktvissen that do actually have a taste for human blood. The losqulas are predatory nienktvissen that regularly feed on large prey, which includes us.

But losqulas are not the only type of nienkvis that prey on large, usually live prey. Considered to be reasonably close relatives to the true squidn'ts, these carnivorous nienktvissen are often referred to as wangvins (Zygopterichthyidae). One the first things anyone remotely familiar with nienktvis anatomy will notice are the large "fins" that flare out from below the eyes. These fins are derived from the barbels seen in other nienktvissen and likely serve as stabilizers and lift generators. An adaptation seen in at least two other unrelated kinds of nienktvissen.

The tiger wangvin (Malascellus tigris), known to live in the Riatis Ocean, is a medium sized species that grows between 150-180 cm long. These wangvins, like most others, are predators with long protruding teeth based on large plates that can all move independently. While they look scary, wangvins are significantly less dangerous than losqulas as they tend to be more wary of their surroundings. It is thought that this wariness might be due to them not wanting to risk their cheek fins getting damaged, as it could pose a large hindrance to their hunting and general life. That said, wangvins are known to get aggressive when they detect blood in the water and there are at least a dozens reports of divers getting bitten in the legs or arms by curious wangvins. Our standard diving suits are multi colored with striped limbs to break the silhouette and deter large predators from attacking, but it seems that these striped limbs can seem like separate, smaller prey animals to the wangvins.

These fish tend not to venture too far out to the open ocean and will usually patrol deeper zones of reefs during the day and come up to the surface at night.

 

Brown Richibi

Most nienktvissen possess 6 or 7 gill slits, with the latter seemingly being the ancestral state. There are a handful however that have even less. The richibi's, as they are often referred to, are conodonts that only have 5 gill slits. That is hardly the only strange thing about them however, as these fish are known to possess a far greater number of functional fins than most other nienktvissen do, moving them in a wavelike fashion similar to how the extinct Anomalocarids of Earth are speculated to have done.

Some researchers have suggested that richibi's might not even be actual nienktvissen at all, but rather another kind of conodont that independently evolved a similar style of locomotion by splitting the ancestral caudal fin into a number of finlets. There is however, hardly enough evidence to confirm this theory and there is too little genetic testing on nienktvissen as a whole draw support from.

Richibi's are almost exclusively found swimming in the coastlines and river mouths tropical and subtropical Miesjeta. The brown richibi (Virrateops fulvus) is a species that can be found inhabiting estuaries, deltas and the waters near river mouths in Bloëca. Spending a lot of time in murky waters, this fish has long barbels with which it can detect food and foe when visibility becomes too low.

It is thought to feed predominantly on plant matter and mollusks, but too little about its lifestyle is known to say for sure.

Whitetip Meadow Coeaai

Much like the sharks of Earth, the coeaaien of Eryobis are subject to rather simplistic names. A prime example of this is the whitetip meadow coeaai (Livadiselache leucacrus), a species of toothed coeaai (order Odontocoeaiida) that inhabits the shallow waters along the eastern coast of Hatèmica. As its name suggests, it has a distinctive white tip on its caudal fin that distinguishes it from other meadow coeaaien.

It is a medium sized species, with the largest individuals reaching around 2 meters long and poses little threat to human divers. It feeds mostly on relatively soft bodied animals smaller than itself such as small fish, nienktvissen and llamplelgans as well occasionally scavenging on deceased megafauna.

As is typical for coeaaien, this species also has two large pectoral fins that are permanently oriented upward to function as dual dorsal fins. While these are mostly fixed, they do possess a small degree of mobility and allow coeaaien, such as this species, a surprising amount of maneuverability and makes them able to turn on a dime. Usually slow cruisers, coeaaien can perform quick bursts of speed to catch their prey and their maneuverability and flexibility allows them to strike fast in many directions around them.

A common species around Hatèmica, it can often be found as bycatch in fish markets on the eastern coast of this continent. It is said that the small, but numerous scales of coeaaien make their skin very tough to chew through, but that the meat underneath is quite tasty. The fact that coeaaien do not excrete urine through their skin like sharks do probably makes them a lot more palpable.

While coeaaien such as this species often remind us of the sharks back home and on many colonies, there is one behavioral trait these fish possess that is most unsharklike. Namely their breeding habits. While sharks practice internal fertilization and often give live birth, the method coeaaien use is more like that of most bony fish. They perform a behavior called spawning, where the male and female freely release their gametes into the water. It likely differs per species and location, but whitetip meadow coeaaien have been observed to dig shallow holes in the sediment or make small "nests" in the vegetation for the breeding pair to spawn into. Curiously, it is often the male that stays behind to guard the eggs while the female goes on to mate with another male, only to repeat the process. This makes them seem like quite dedicated parents and indeed, the male will even keep guarding the young after they hatch, but as soon they start growing teeth, which is usually after around a week, the male is just as likely to eat them as guard them.

Green Sjaul

Far out in the open ocean is where you can often find the fastest swimming animals. Nowhere to hide, in this watery desert, the only defense for anything that isn't translucent is speed. Fish that live here are often thunniform and carangiform in body shape for hydrodynamic efficiency.

It should therefore be little surprise that nienktvissen, conodonts that do not possess a typical fish like body, are not that common far out in the ocean. There are a number of very large bodied nienktvissen that carve out a living in the open ocean by feeding on plankton or small shoaling crustaceans and fish, but these do not typically frequent the surface.

There is one kind of nienktvis that can be found at high sea, the sjaul. Scientifically known as the genus Cephalopteron (and possibly others), there likely at least a dozen species of sjaul to be found in the oceans of Eryobis. 

These are peculiar looking animals, even for nienktvis standards.

Their bodies are cone shaped and possess four very large fins, behind which a much smaller fin is located. It is thought that the large fins are used for propulsion while the smaller ones provide stability or aid in changing or maintaining direction and stability. In addition, sjauls have another pair of "fins" located on top and below their head. These derive from the ancestral barbels present in most nienktvissen and are likely a feature that sjauls evolved convergentlty with some other unrelated nienktvissen such as vlagops. It is still unclear what exactly these are used for.

The green sjaul (Cephalopteron virens) is a species that can be found cruising the open waters of the Tinjis Ocean in its warmer regions. Here it feeds mostly on free swimming arthropods, small fish and plankton. The tooth elements in the back of its mouth are blunt and rounded, which helps them crush the food that they cannot swallow whole.

Sjauls are a much desired catch for fishermen because of their muscular bodies and crustacean induced flavor. But it is not just fishermen that want to eat sjauls.

Because these fish are quite common and often form shoals of several hundred individuals, they get preyed upon by a wide variety of both marine and aerial predators.

The soft bodies of sjauls make them favorable prey for ritsuara's and other Fermourodonts, which often emply hit and run tactics where they will slice a sjaul in half and come back to eat when it has become incapacitated. 

Blueside Molula

Tropical reefs are home to some of the most colorful and diverse wildlife in the oceans. This is as true for Earth as it is for Eryobis. The Caddis Sea and the shallow waters around the Rubiëran archipelago are home to some of the largest reefs on Eryobis and consequently, are home to some of the most stunning aquatic creatures to be found on this world.

A prime example of this is the blueside molula (Molula cyanopleurus), a splendidly colored species of nienktvis. Named for its outward resemblance to the molas from Earth and given the Latin suffix -ula for its diminutive size. Molulas are quite common in tropical regions all around Eryobis, but Rubiëra appears to be especially rich in molula species, with possibly over a dozen having been observed.

The blueside molula is a quite typical molula species most easily distinguishable by its bright blue side with yellow under-borders and white stripes. Like all molulas, it has evolved four of its barbels into large and flat palps for the purpose of feeding. This adaptation is also seen in cyclopses and it is currently thought that molulas share a fairly recent common ancestor with these creatures.

Like some other molulas, it is a carnivore that feed predominately on small arthropods that live in the reefs. With their palps, they are able to manipulate their food to a great degree and have been observed using them to break the pincers off crustaceans in order to eat them without getting injured.

While we have no evidence supporting the fact, Rubiëran natives claim that molulas are poisonous to eat. It is said they occasionally rub dead molulas on their darts to weaponize their alleged toxins.

Sixgill Vibrissotact

The Vibrissotactus hexanchus, more often known as the sixgill vibrissotact, is a small species of nienktvis native to the coastal regions of eastern Guralta. It is commonly found in algae forests where it perfectly blends in with the vegetation.

Based on stomach contents and the morphology of its teeth, it has been determined that these fish are omnivores, feeding on both algae and invertebrates such as various mollusks, echinoderms and crustaceans. Compared to its relatives Vardichthys and Xegeloichthys, which are also members of the family Vibrissotactidae, the sixgill- is a lot less carnivorous. Due to the fact that sixgills- do not possess the bioluminescent organs that other members of the family possess, it is currently thought that sixgills- and other surface dwelling members are the "standard" for the family, while various lineages have independently colonized the deep sea over time.

Sixgill vibrissotact are territorial animals that passionately defend their own little "gardens" of algae against intruders and small carnivores. Because of this, they are not particularly common and not often consumed by the natives or our explorers. Despite this, they are said to taste quite good, with a decent fat content and sweet buttery taste that reminds of crayfish, which is likely due to the fact these fish consume a lot of crustaceans.

Trichasterops riaticus

In the depths of the Riatis Ocean in the north of Eryobis lives a funny looking creature. Akin to a small black squid with four large fins and six small tentacles tipped with bioluminescent bulbs. But it is no squid, it is in fact a type of nienktvis. 

Known as Trichasterops riaticus, this hand sized little fish is best known for its black, leathery skin and bioluminescent organs on the ends of their flattened barbels. It is theorized that these are used to lure and guide plankton and other prey towards its mouth in a similar manner to the lantern leviathan, of which it is suspected to be a close relative.

Not much is known about its lifestyle because it has never been properly observed in the wild. All we have of it are dead specimens that were trapped on deep lines and fleeting ROV footage often rarely more than a few second long. One thing we can say for sure is that Trichasterops are afraid of light, which could indicate that there are other, possibly larger predators in the abyss of the Riatis that also use bioluminescence to hunt.

 

Horse Headed Squidn't

First discovered on a native fish market in the region of Lotharcan Miesjeta known as Vermilijë, a strange looking fish with a face only a mother could love and teeth that reminded of ancient 20th century caricatures instantly caught the attention of the researchers that saw it. They wished to buy the fish to further study it and, as was and still is pretty common, the salesman scammed the hell out of them. While the researchers that bought the fish have never confirmed the price they paid, it is rumored that they paid with a silver wristwatch or some other precious metal jewelry. What ever they might have traded the fish for, the salesman they bought it from had soon after bought out nearly every fisherman in the town, meaning that the price the researchers paid for the fish equated to several million in local currency.

The fish they bought would later be identified as a horse headed squidn't (Thlipsiodon bucephalus), a fish which is actually quite common in the tropical, subtropical and temperate waters of the Tinjis Ocean.

The peculiar teeth that caught the attention of those researchers are quite unique among nienktvissen due to the fact that they are large, blunt and globular, which is pretty much the opposite of the teeth that most nienktvissen have. These teeth, combined with the stomach content the researchers examined in their overpriced specimen led to the conclusion that horse headed squidn'ts are durophages, specializing in feeding on tough and armored prey.

As later live observations would confirm, the bulk of their diet consists of planktonic and nektonic pectinauts, which in many ways seem to fill ecological roles that the extinct ammonites did back on Earth in the Mesozoic period. Like these prehistoric cephalopods, pectinauts are extremely abundant in the oceans of Eryobis. It is therefore no wonder that creatures such as the Thlipsiodon would specialize in such an common and reliable food source.

Since the horse headed squidn't tends to stay near the surface and does not seem to dive more than a hundred meters below the waves, it has been able to become among the best studied nienktvissen to date.

These fish usually grow between 1 and 1.7 meters in length with a wingspan of roughly 80% that length. They only have two, long whiskers that sprout from the lower jaw. Autopsies have revealed that these barbels essentially serve to detect pressure changes and sound waves in the water. 

The seven gillslits of this fish are peculiar in that the exhausts seem to be angled to various degrees per individual slit. This is very likely evidence that nienktvissen use their gills as a way to steer and change direction. 

While not much is known about the mating habits of this species as yet, what observations have shown is that they exclusively happen at night at around 30 meters or below.

Despite being called the horse headed "squidn't", Thlipsiodon is not a member of the Teuthomorphichthyidae, better known as the "true squidn'ts". Its colloquial name is the result of early explorers giving animals that looked superficially similar the same name for the sake of simplicity.

Thlipsiodon is in fact not even that closely related to the true squidn'ts and rather came from a different lineage that convergently evolved a similar body shape. Unfortunate as it may be for classification, the name seems to have stuck.

Umbral Losqula

For those who have thalassophobia, Eryobis is a very pleasant place to be. While there may not be any true sharks present in the seas of this world, some would argue that the realm beneath the waves of Eryobis harbors creatures that are even more terrifying.

While squidn'ts tend to get a bad reputation because of one tragic incident that very early after the first explorers set to sea, they are typically quite harmless. The same can not be said for another type of nienktvis. 

The Pleuropristidae, commonly known as losqulas by the explorers, are a family of carnivorous nienktvissen that are ranked as being the most predatory among their kind. Most nienktvissen and squid'ts are known to feed on prey smaller than themselves that can be easily swallowed. Losqulas on the other hand, seem to have a preference for prey equally to- or larger than themselves. They often seem to specialize in shredding their prey to bits while its still alive. Their teeth are long, sharp and serrated and with the various tooth elements being able to independently from each other, losqulas excel at mincing their prey and inflicting great blood loss. 

That said, they do not shy away from scavenging and it is not uncommon to see them congregating around the carcass of a large deceased animal.

The umbral losqula (Teutharpax umbrosus) that occurs in the Voûlic Ocean south of Miesjeta is a large member of this family that can grow over 2.5 meters long. One might look at these creatures and presume they are awkward swimmers, but these fish are deceptively fast. With two very large frontal fins and four auxiliary posterior fins, umbral losqulas can reach over 30 km/h in short bursts of speed. This, combined with their inquisitive nature makes them quite a nuisance for divers, who nowadays always need to be armed whenever they go on a dive in the Voûlic Ocean.

Umbral losqulas have been observed often following boats to feed on scraps and to steal the harvest of fishermen and are known to hang around native port cities in the south of Miesjeta, occasionally taking their toll in the form of people, most often children, going for a swim.

What makes these fish so dangerous is the fact that they most often hunt around dusk and dawn when they are the least visible to the eye. While one could be forgiven for thinking losqulas do not come close to shore due to their morphology, these carnivores are very much capable of swimming on their sides to enter water as little as 50 centimeters deep.

Not much is known about the lifestyle of these losqulas. As of yet it is uncertain if they are sedentary, territorial or migrate between feeding grounds. What is known however is that they always seem to stick to the continental shelf and will not be encountered in the deep open ocean.

Lesser Sideray

All along the northern shorelines of tropical Miesjeta, you can find a most peculiar looking creature swimming through the sand. From a glance it resembles a Batomorph from Earth, better known as a ray, but the resemblance is only superficial.

Upon closer inspection the differences become more apparent. One anatomical trait that instantly determines this animal to not be a Batomorph is the fact it has gills on its "upper side". To those less knowledgeable on the anatomy of Batomorphs, there is another trait this Eryobian animal possesses that should make it clear that this no true ray.

The creature has but a singular eye on its entire body, adorned with a pupil possessing three prongs to form a "Y" shape. No vertebrate animal from Earth is known to naturally have such a trait. For this reason, many researchers refer to these ray like creatures as cyclopses. Unfortunately for them, the scientific name of Cylopoida is already taken by a group of copepod crustaceans from Earth. Instead, a name that is often used in addition to cyclops is sideray. There are also many researchers who prefer to refer to these creatures by their scientific name solely, as Monobatopsids.

Further research revealed Monobatopsids to actually not only be related to nienktvissen, but that they are actually very derived members of this group. In hindisight, it should have been quite obvious that siderays are nienktvissen. They share some key characteristics such as the lack of jaws, but presence of well developed plate like tooth elements. The six individual gillslits should also have been a dead giveaway since no other non-conodont animal on Eryobis possesses this trait. The presence of a number of barbels sprouting from the lips is also a strong indicator of their identity as nienktvissen.

So it became clear that cylopses are merely nienktvissen that opted for a demersal lifestyle by laying on their sides, but they are not born this way.

When siderays hatch from their eggs, they are extremely small and are virtually indistinguishable from other, related nienktvis larvae. For their first weeks of life, they develop much like other nienktvissen, gaining their characteristic large fins to propel themselves with and this stage, they possess two eyes, one on each side of the body.

But as they mature, they start changing. They start living closer to the seafloor and begin favoring one side over the other. Whether this is left or right usually differs per species or subfamily. They start living near the substrate and will instinctively hide in the sand. It is at this stage that the eye on the side that faces the seafloor starts atrophying until it is completely resorbed into the body.

Why this happens instead of the migration of the eye like is seen in Pleuronectiformes and Planosolincolans is unclear. One would be forgiven for thinking that the entirely cartilage "skulls" of nienktvissen would make such a migration easier than if the skull was bone.

One of the first aquatic animals to ever be encountered on Eryobis by explorers was the lesser sideray (Rajacyclops minor). This creature can commonly seen inhabiting the shallow coastal waters all along the northern coast of Bloëcan Miesjeta, which is ofcourse where the first landing site and colony were made.

It is a small critter, barely two hands wide and only a few centimeters thick. This makes it perfectly adapted for a life in the sand in waters where few predators can reach it.

Yet this little cyclops is often the largest predator in its sandy environment. It feeds on a plethora of invertebrates such as gastropods, sedentary bivalves, pectinauts, brachiopods and small llamplelgans. 

As with many sideray species, the lesser sideray possesses a three pronged pupil in its singular eye. It is thought that this peculiar shape helps siderays see from multiple angles. An imperative ability for an animal that spends most of its time hidden in the sand.

Common Vlagop

The common vlagop (Veleovoltus communis) is one of several species in the genus Veleovoltus that can be found in the Vyaris Ocean, but as its name suggests it is the most common. 

This small nienktvis often occurs in huge shoals of several thousand strong and undertakes long seasonal migrations between the continents of Miesjeta, Guralta and southern Tlèëa. Curiously, the seasonal behavior of this species is largely restricted to the populations that live north of the equator, while the populations south of the equator tend to be more sedentary. As of yet, no solid explanation for this phenomenon has been offered.

As small and abundant planktivores, these conodonts are near the base of many food-chains where they permanently occur and often become seasonal feasts along their migration route.

Being small than a human hand on average, there is a great many predators that will happily make a meal out of a vlagop.

This includes the native peoples of Eryobis, who often harvest these small fish by the dozens by casting nets. Human explorers and researchers are also no strangers to eating vlagops. These creatures are so common in the Vyaris Ocean that even our colonists are allowed to occasionally catch them.

One characteristic of vlagop that immediately catches one's eye is the "dorsal fin" that goes from the mouth to the second gillslit. This "fin" is actually a membrane that stretches from a single large cartilage reinforced barbel on the upper lip that permanently stands upright.

It is thought that this fin serves to stabilize the vlagop as it swims, although it does appear that there are surprisingly many small muscles attached to this fin, which could indicate that it might also serve as a rudder that works in tandem with the terminal posterior fin.

 

Northern Stonesprite

When explorers go wade or swim near rocky beaches in Tlèëa, they often come back with fresh bite wounds. Four small punctures, usually on the feet or ankles, that can bleed for a surprisingly long time.

The perpetrator?

The northern stonesprite (Talusictus borealis), a small species of llamplelgan that lives in shallow rocky habitats all along the coast of Tlèëa. It is grey in coloration and blends in perfectly with the rocks and for a good reason. It is an ambush predator that lies in wait for some unsuspecting prey to swim by.

It mainly feeds on pectinauts, but crustaceans, small fish, conodonts and other llamplelgans are also on the menu. 

Once prey is in range, it rapidly extends its esophagus and turns it inside out to reveal four large copper coated teeth. If prey is impaled by these teeth, it is game over and the stonesprite quickly draws its esophagus back in.

Additionally, these teeth seem to be coated with an anticoagulant venom that prevents blood from clotting. So when one of our researchers gets bitten by a stonesprite, either out of self defense or mistaken for prey, the researcher has actually been envenomed by a substance that could prove deadly if it was injected in a larger dose.
 

Red Paddlepalp

If you ever find yourself exploring the vast underwater meadows off the east coast of Hatèmica, keep your eyes peeled for a most curious little critter.

They are small and lightning fast if they need to be and to top it off, incredibly well camouflaged for their environment.

Red paddlepalps (Remmanula rubeus) are small llamplelgans that, while seemingly elusive, are actually very common in the shallow coastal waters of Hatèmica. These critters often seem to walk along the seaweed, but what they are actually doing is "tasting" them for traces of food.

Red paddlepalps are carnivores that feed mainly on gastropods and small pectinauts that they share the meadows with. Once they have located their prey, they will grab onto it with the hooked pads on the ends of their tentacles before inverting their esophagus to swallow their prey whole.

Despite being called "red" paddlepalps, further examination has revealed that they aren't universally red in coloration. They can come in various shades of grey, brown and even blue, although this is most likely because they contain chromatophores within their skin which allows them to change color based on their environment.

 

Ægiric Smooth Llamplelgan

While Eryobis might lack Cephalopods of any kind, it has become clear that llamplelgans like this species fill the niche of Coleoids for a large part. Being able to swim almost omnidirectional and with all those tentacles, the resemblance is actually uncanny.

A common sight for our exploratory vessels and a common catch for fishermen, the Ægiric smooth llamplelgan (Leiodrilos aegiricus) measures between 30 and 50 centimeters long in body on average, with the tentacles adding another 20 or so centimeters.

This species feeds mostly on small crustaceans, fish, pectinauts and other llamplelgans that live in the upper water column. It travels in large shoals up to several hundred individuals strong, although this is mainly for protection, as this species is preyed on by numerous larger predators.

It can often be found in native fish markets that border the Ægiric Ocean. Curiously, some explorers have stated that the flesh of llamplelgans resembles that of squid in both taste and texture.

Clade overview: Coeaaien and Bunnyfish

Some of the earliest reports from explorers mentioned the presence of sharks in Eryobian waters. 

Knowing that Eryobis is world where all its life has a terran origin, this mention of sharks was initially overlooked and shrugged off as a quite likely plausibility, given the incredible age of Elasmobranchs.

However, when footage of these supposed Eryobian sharks was properly examined, something about them immediately seemed off.

They did not have the 5 to 7 gill slits typically associated with sharks, instead possessing an operculum and thus only one gill opening.

They appeared to have no pelvic fins at all, their first dorsal fin looked as if it was laterally split in two and the caudal fin, while heterocercal like a shark's, appeared to have three distinct lobes.

Those among the explorers with knowledge of terran paleontology suggested that these creatures could be Holocephalians, related to the chimaera's of Earth. For quite some time, this was considered to be the most likely origin of these "sharks", since it technically fitted within the suggested Eryobian evolutionary timeline.

As specimens were examined up close and subjected to testing however, the idea that these were even Chondrichthyians at all was quickly discarded.

In pretty much all genetic tests, they came out as being closest related to the coelacanths and more specifically, with their closest relatives being the Anisospondyls. 

When more fossils of prehistoric Eryobian fish were unearthed, the pieces fell into their place.

These were no sharks, they were Lagotoichthyiiformes or rather, bunnyfish.

Their close relation to the Anisospondyls now made sense, for these now land dwelling creatures are Planosolincolans and thus technically bunnyfish themselves.

The "dorsal fin split in two" are actually the pectoral fins which had shifted far up the body to act as dorsal fins and what seemed to be the pectoral fins are actually the pelvic fins that moved far to the front of the body, as is seen in all bunnyfish.

Reconstruction of Lagoselache durus, the likely ancestor all coeaaien and kin

It seems that bunnyfish were hit extremely hard in the mass extinction known as the World Scarring, with most genetic evidence suggesting all modern forms can be traced to a single ancestor that lived around 120 million Eryobian years ago.

In fact, a likely candidate for this supposed ancestor has actually been found in rocks dating to the early Thyellian: a small fish named Lagoselache durus. 

This fish shows the characteristic "double dorsal fins" and three lobed heterocercal caudal fin, demonstrating that this condition was ancestral to all modern forms.

 

Some examples of living coeaaien and kin

At some point, the term "coeaai" (pronounced "koo-aye") became widely used among explorers to refer to the more shark like bunnyfish, likely a contraption of coelacanth and the ancient dutch word for shark "haai". 

All the modern bunnyfish have been classified as supergroup named Lagoselachia, after the oldest known member. Despite this name, not nearly all of them look shark-like. And apparently some of the most shark-like members of this group evolved largely independently. A good example of this are the toothed coeaaien and the plated coeaaien. Both of these look very much like sharks and resemble each other quite a bit in overall anatomy, yet genetic testing suggests these split over 80 million years ago and both have many relatives that do not look particularly shark-like.

Then ofcourse there are also Lagoselachians that surrendered their ancestral body shape for that of a more typical bony fish or even turned it into something else entirely.

The modern bunnyfish and coeaaien are very diverse in body shape, yet they are not very numerous in species compared some other Eryobian fish orders. Still, they are not an uncommon sight in any Eryobian waters and often fill critical parts of the ecosystem they find themselves in.

Rubiëran Sandsprite

The shallow waters of Rubiëra and the Caddis Sea are a hotspot for marine life because of the warm tropical climate and nutrient rich currents that feed its inhabitants.

In in the shallowest parts, where the sand is barely below the surface, it is not uncommon to see a llamplelgan fluttering and darting around below the gentle waves, more specifically a Rubiëran sandsprite (Ammoxoticus orientalis). 

This species can grow to around 25 centimeters long and is primarily a scavenger that feeds on what ever the waves carry to the beach. 

Living in the shallows where they are very much visible to predators from above, Rubiëran sand sprites are able to dart away in very quick bursts of speed and will hide in the sand if they feel the need to. Additionally, iridescent, almost mirror like skin and translucent fins to help them blend into the environment.

Rightfully so, because a great number of predators from flying Stauropterygians and Chalacheiropterans to fish and other llampelgans will try to make a meal of a sandsprite whenever they see one. Even the native Eryobians are known to catch sandsprites on occasion.

 

Ægiric Whiskerlure

Five thousand meters below sea-level is hardly a place one would expect to find light.

Yet, when an ROV was sent down into the abyss of the Ægiric Ocean, it countered light.

Not just any light, but reddish orange light. A color that should have no place this deep underwater because most animals that live this deep cannot even perceive this color.

But that was the exact purpose of the creature the light was attached to.

The Ægiric whiskerlure (Xegeloichthys fotophoneus) is a species of nienktvis that is among the few Eryobian deep sea creatures capable of seeing red and orange light, a fact which it exploits to the fullest. By utilizing this "invisible" light, it is able to see its surroundings and prey quite clear, while its prey has no idea it is even there.

Art by BobsicleG

Although this is not actually completely true. The whiskerlure has another tool in its arsenal, one which it uses to lure its prey closer.

As the name might suggest, this abyssal nienktvis has a lure on the end of one of its whiskers. This lure however is far more complex than what is commonly seen in deep sea creatures. 

The lure itself is shaped like a small nienktvis.

This form of predatory mimicry is very rare and was only ever documented in certain squid and snake species from old Earth.

The lure of this species even has small bio photophores to create the illusion of eyes.

This lure, together with its use of "invisible light" make the Ægiric whiskerlure an excellent predator that uses its built-in headlights to spot its prey and then deploys its specialized barbel to lure its prey toward its mouth, where rows upon rows of sharp needle like teeth are waiting.

The Ægiric whiskerlure grows to around 13 centimeters long, making quite a sizable creature this deep below the waves.

 

Night-sky Fish

 Deep down, in the cold dark abyss of the Ægiric Ocean, lives a creature that looks like it should have no place in this mortal universe. 

Skin black as coal, sunken eyes through which no light shines. 
Massive translucent teeth and a face full of barbels that wriggle in every direction.

Yet at the tips of these fleshy whiskers are small bulbs of light.

The skin of this hideous creature soaks up all the light so all that can be seen are ten tiny lights, flickering like stars in the dark of night.

The identity of this monstrosity? 

It is actually just a night-sky fish (Vardichthys devorator), an abyssopelagic nienktvis barely 7 centimeters in length. 

Art by BobsicleG

This animal behaves much like an anglerfish from Earth. It hangs in the water column, waiting for prey to swim by and get attracted by its bioluminescent lures.

Its terrifying teeth serve not to impale or slash, but rather just to trap and make sure prey does not escape from its maw.

As with many other deep sea fish, it has a very flexible stomach that can expand to a great size to encompass a meal.

Not much else is known, for this creature was not observed in its natural habitat. Rather it was pulled to the surface when it became ensnared on a deep line.

Good for us so we can study it, less for it because it died from decompression sickness.

Clade overview: Nienktvissen

The oceans of Eryobis are teeming with life, from worms that look like straight up aliens to scallops that decided they wanted to be fish.

Obviously there are also still vertebrates in the oceans in the form of fish and secondarily aquatic land vertebrates, but there is also another kind of "vertebrate" that lives in these oceans. Conodonts, while completely extinct on Earth for hundreds of millions of years, are still alive and thriving in the Eryobian seas.

Genetic testing suggests there were at least seven different conodont lineages to survive the mass extinction known as the World Scarring. 

As they always were, many of the still living conodonts are small, eel-like inconspicuous creatures. But there is one order that stands out, being among the most recognizable animals on Eryobis: the Teuthomorphichthyes. 

Better known as the nienktvissen, squidn'ts or "murder-molas", after one terrible incident, these conodonts are some of the most objectively easily identifiable creatures in the oceans. 

Nearly all of them swim not by undulating as most condonts would, but by flapping their very large dorsal and ventral fins, which were modified from the ancestral caudal fin. This gives them a style of swimming akin to the Molidae of Earth, which is ofcourse where the nickname "murder-mola" comes from. The majority of nienktvissen also possess from five to seven gill-slits and numerous long whiskers and tendrils near the mouth, which serve all kinds of purposes from feeding to steering.

Another common characteristic is their tooth elements which are often plate like and tend to stick out.

The hypothetical ancestor of the Nienktvissen

Nienktvissen are incredibly diverse and can be found in every ocean, sea and even in some freshwater habitats. They range in size from just a few centimeters long to gigantic oceanic cruisers like the lantern leviathan with its ten meter wingspan. There are even some forms which have evolved to live close to- and in the sediment, adapting to live on their sides like flounders and Planosolincolans. Unlike these true fish however, such nienktvissen have instead lost the eye that would permanently face down, essentially becoming cylcopean. 

Some examples of living nienktvissen

Despite their incredible diversity and richness in species, nienktvissen are notoriously difficult to classify among themselves. The terms "nienktvis" and "squidn't" were often interchangeable for early explorers, but recently it was established that squidn'ts are a type of nienktvis, specifically those within the Teuthomorphichthyidae, which are the true squidn'ts. But because of the interchangeability of the names in the early days of exploration, there is a lot of animals called "nienktvis" that should be classified as a "true squidn't" and vice verse a lot of "squidn'ts" that are outside Teutomorphichthyidae and are thus nienktvissen or "false squidn'ts". 

The fact that genetic testing has also yielded little result so far does not help with classifying them either. So while species and genera can be placed within families, those families can often not really be placed within a larger group.

Cladistics: Rubieroptera

Stauropterygians are a very old group. Possibly diverging as early the late Thyellian and being even older than the Monotoalosia, they are the most basal living Eusymmetrodactyls.

But they are by no means primitive. In fact, Stauropterygians are the single most diverse species rich and diverse order of Anisospondyls to have ever existed.

But because they are so old, they have a decent number of ancient "leftovers" among their ranks.

While there a good amount of those leftovers are true relics and often the last remaining members of their respective prehistoric families, there is one group of basal Stauropterygians that does actually appear to be a (mostly) monophyletic grouping: the Rubieroptera.

This group of mostly, but not exclusively flightless Stauropterygians are hypothesized to have evolved from some of the very first Stauropterygians to reach the paleo-continent Magna-Rubiëra, which ofcourse was completely isolated from the paleo-continent Kwispuul where Stauropterygians evolved. Even to this day, the majority of morphological diversity among Rubieroptera can be found in the Rubiëran archipelago, from which the group draws its name.

The most basal living members of the group look exactly like what one would expect a secondarily flightless basal Stauropterygian to look like.

They are usually small bodied creatures no bigger than a turkey, with a long tail, a short beakless but toothed skull and small arms with clawed fingers and often a small remnant of what used to be the wings.

It is likely all other Rubieropterans evolved from animals like this.

One noticeable family of Rubieropterans that still live in Rubiëra are the Thanatrigidae, a family of large bodies predators that are the undisputed terrestrial apex predators of the Rubiëran isles. Some species like Thanatrix imperator can weigh up to 400 kilograms. These fierce predators often hunt by lying in ambush or lunging from trees and will try to impale their prey with their large and strong claws before delivering the killing bite. 

A family of Rubieropterans that are relatively closely related to the Thanatrigidae are the Inermavidae. The bulk of this family lives in Augadrian Tlèëa, with some species also occuring in Wyndraë and Lehseppi. These flightless and in fact completely armless Rubieropterans did not reach Tlèëa by island hopping, but were brought there by plate tectonics as Magna-Rubiëra broke apart and the Inermavids were marooned on the northern part that drifted towards Tlèëa.

The largest group within Rubieroptera is the Exypnophonea. The most basal members of this group are small to medium sized arboreal carnivores that live all over the Rubiëran archipelago. Uniquely among Stauropterygians, Exypnophoneans have wrists that can be pronated and possess opposable "thumbs", allowing for incredible maneuverability in the canopy.

This, combined with their high intelligence, makes such Exypnophoneans a threat for everything that lived in the trees in the Rubiëran isles.

But a strange thing happened when some Exypnophoneans got stranded on Lotharca when it broke apart from Magna-Rubiëra. As the landmass started becoming more arid and the forests the Exypnophoneans called home started disappearing, they were forced to adapt or go extinct. And adapt they did.

From these Exypnophoneans that were forced out of the trees evolved the Keshtaridae, a family of large to very large hypercarnivores. With their long legs, straight backs, long tails and large arms and claws, they bear some resemblance to the Megaraptorids of Cretaceous Earth. Like them, the Keshtarids mainly hunt by using their sharp claws to inflict deep slashing wounds and cuts on their prey to induce massive blood-loss. 

Curiously, they evolved their caecal pair of front limbs to be permanently held below the mouth and act in tandem with the jaws, an adaptation akin to the Brachiostome condition. 

These claws have been observed to be used to help manipulate food, serve a function in communication and to be used to dig deep into (often still living) prey. Additionally, the skin between these arms has grown together and has created a pouch which they often use to transport their young, food and trophies.

Which is perhaps the most terrifying aspect of the Keshtarids. They are extremely intelligent.

They are social creatures that typically live in family groups, communicate through a great number of vocalizations and body language and have been observed to use tools and elaborate schemes to hunt their prey. 

Just exactly how intelligent they are has not yet been determined, but it seems that all of them are at least on par with Hominids and Corvids, although some legends among the natives suggests that they are able to understand and even speak the languages of the native tribes they share territory with.

Slender tailed Gingûr + Brown Flailear

On one of our first expeditions to the continent known as Guralta, we arrived at a coastal marshland. A vast salt- and brackish water delta stretched for many miles along the coastline and extended deep inland, following much of the length of the main river that fed it. 

This region of eastern Guralta is known as Kwispuulië. It is a variable land with a largely tropical, but also somewhat seasonal climate that depends on monsoons for much of its water. This vast delta however, seemed less dependent on the monsoons and appeared to be lively and moisturized for most of the year.

Disembarking from the main research vessel, a team took a couple of smaller boats to enter the delta. 

It was teeming with wildlife. Six winged insect like animals were buzzing around their ears and all over the forest they could hear the screams, cries and songs of numerous untold creatures.

At some point, they spotted a large, eight legged, vaguely mammal like creature with two long tendrils sprouting from its what appeared to be its ears. It was an Arachnothere for sure, but not one they had seen before. It appeared to be foraging along the river bank for washed up vegetation and plants growing on the waters edge.

Before long however, the peace was disturbed. 

A massive animal lunged from the water in a way reminiscent of crocodiles of Earth. As it prepared to strike, its "lower jaw" split open. Large spikes lined the jaws, perfectly adapted to impale prey.

It was over in a second...but the predator missed. It had lunged too early and came in short, allowing the Arachnothere to flee.

 

The crocodile like predator was later determined to be a Slender tailed Gingûr (Gingurius leptouros). This species is native to eastern Guralta and grows to about 7 meters long. 

Gingûrs (Ginguridae) are Parasymmetrodactyl Cryptognath Anisospondyls and are a common sight in many tropical and subtropical regions around the world.

In general, these creatures are near perfect analogues to Earth's crocodillians, being largely semi-aquatic, cold blooded ambush predators covered in osteoderms and tough scales. 

They are Anisospondyls, but there's one thing about that their appearance that does not exactly fit the stereotype: their jaws. Gingûrs possess a long "upper jaw" that, while toothless, is lined with sharp keratinized bony spikes. 

But this is no true jaw.

Rather it is an extended bone that sprouts from below the eyes. A gingûrs true jaws are below it. These jaws, like those of all Anisospondyls, open sideways to reveal a large number of teeth inside. But they, like the "upper jaw", are also lined with keratinzed bony spiked on the visendal side. 

Curiously, gingûrs possess a unique jaw mechanism that allows their true jaws to open both sideways and be moved up and down. This reveals the purpose of their strange heads. These jaws work together to impale prey and slam it against the "upper jaw". This mechanism bears some similarities to the jaws of the Haidomyrmecinae ants of Cretaceous Earth.

The eight legged creature that was initially spotted was a Brown Flailear (Kopanotus spadix), a large herbivorous Hesparachnine native exclusively to the forested regions of Kwispuulië. 

These animals possess sharp rounded beaks, perfectly adapted to cut plants with. They are toothless, but to compensate they ingest stones to function as gastroliths. 

The males of this species, similar to most flailear species, grow long tendrils from the base of their ears. These ears, unlike those of mammals, are supported by many small bones. As such, they possess a large degree of control over the motions of these "flails". 

These tendrils have rhombus shaped tips that are lined with small iridescent scales, giving them a blue, green and yellow shine. Predictably, these are used for sexual display and serve little purpose otherwise.