Os oris

**Os Oris (Or bone mouth)**
A Medium sized predator that lives in the estuaries and it's distant ancestor being the Gomphiobia, it can grow over 3 meters long and has evolved "jaw" like appendage on the top of it's bottom part of the skull which has the ability to close. 2 of its proboscis's evolved into long tentacles that help it taste and locate prey and a mate, they can also be used for hunting, only 1/5 of the length of the tentacles are outside because how long they are. The 3rd proboscis which is in the middle is short but large to help it swallow prey, it also swallows water trough the throat which the water runs trough 2 large gill openings that let the carbon out and the openings can be used for prepolsion. The 2 fin like spikes are used to latch onto large objects that are underwater such as rocks to stay and rest in the current when migrating. They reproduce in bodies of water that are in higher altitude so they use their powerful tails to swim up and build ditches to lay their eggs in. They don't have the greatest eye sight as they mainly are active in dawn and Dusk.

## **Species from the genus *Neos***

#### -**Silver os *(Neos argentum)***

**Creator:** M o t h/gonb

**Clade:** Os Oris (Ostrigonia)

**Habitat:** Both slow moving and fast moving waters of the taiga in Terra septentrionis.

**Size:** 50cm to a meter in length and about 20 cm wide.

**Diet:** Carnivore.

**Reproduction:** Eggs, spawning.

Being the smallest of the three species, the Silver os is very common in the these fast flowing rivers. Travelling in large schools which insures their safety, there can be atleast 50-100 of them in a single school. They posses large eyes that they use to spot both danger and prey. They have a silvery shimmer to them which can sometimes be blinding if the weather is right and in the right direction, however some predators may find this attractive and seek it out as food.

They live for about 5-6 years. The adults build nests in shallow water and in between large boulders which make a good shelter. They make ditches in the ground before they pair up, females are larger and fat with eggs. The female will lay brownish to grey eggs which blend in with the soil to ensure they are well hidden, the adults will usually leave but more experienced males will guard the nest.

These make great food source as they posses special vitamins and fatty acids that may be benificial. Their fatty acids can be pretty good for many carnivores and these fatty acids will help trough the winter as they are energy rich.

#### **-Tawny os *(Neos fuscus)***

**Creator:** M o t h/gonb

**Clade:** Os Oris (Ostrigonia)

**Habitat:** fast and slow flowing rivers in taiga ofTerra septentrionis.

**Size:** 1-1,5 meters in length and 50 cm wide.

**Diet:** Carnivore.

**Reproduction:** Eggs, spawning.

These larger os posses way more fatty acids which gives them their larger appearance, they'll feed on the smaller silver os and cannibalise juveniles of Tawny os's. They travel in small groups of 3-6. These stay more to the bottom and in a single location, waiting for unlucky prey to come to them instead. They'll rest on the bottom aswell, locking their bony fins in between the cracks of rocks.

These live up to 7 years and spawn in early spring. Similarly to the silver os they'll build a nest in a shallow spot or in the cover of large boulders. The males fight over females and display their "tusks" which are i front of the eyes. They lay up to 200 young and they hatch in 12 days in their larval stage.

#### **Helljaw os (Neos infernomandibula)**

**Creator:** M o t h/gonb

**Clade:** Os Oris (Ostrigonia)

**Habitat:** juveniles inhabit cold fast and slow flowing rivers and adults inhabit terasept Lake.

**Size:** 1,8-2 meters in length and 80 cm wide.

**Diet:** Carnivore.

**Reproduction:** Eggs, spawning.

This is one of the largest Os's that are currently living, feeding on just about anything, from small silver os to medium land animals that fall in or try to cross, even flying animals will be on it's menu if they get too close. It'll get them by jumping out of the water and into the air and catching it with it's formidable Jaws. They are mainly solitary and will usually fight off their opponents.

These predators are fast and streamlined in their environment, easily gaining the role of the apex in the water. Their tail type is perfect for powerful beats trough the strong current which they manage to get trough easily due to how powerful they are. These are more pike like than most other os but still have a trout like profile. They are observed building gravel nests, which are just ditches in the ground. Due to their nesting method, they end up digging up lots of nutrients which flora can take and will good for growing. These nests are made by the beasts by simply beating their tail into the gravel. Due to their cold water Habitat, they live longer and need to eat less, they live up to be 20 years and eat less, only once a week mainly due to their activity. They lay up to 100 eggs which blend in with the substrate, after 27 days they hatch and will usually hide in the substrate and rocks, feeding on tiny organisms, once they reach a more reasonable size they'll swim out into smaller rivers and streams and start feeding more proper prey.

## **Species from the genus *Characios***

#### **Characin os (*Characios characios*)**

**Creator:** M o t h/gonb

**Clade:** Os Oris, Ostrigonia

**Habitat:** colder regions of Terra septentrionis and lake Terasept.

**Size:** 5-10 cm long.

**Diet:** Omnivorous, both plant matter and small animals.

**Reproduction:** spawning, eggs.

Named after tetras whivh are on earth, these cold dwelling fish have similar behaviours and such. They can live in giant schools, largest ones can have up to 30 000 individuals that wary in size, from 5-10 cm. Males are on the smaller scale while females are bigger. These are mainly diurnal and travel quiet abit in rivers and lakes, however their main lake is Terasept. Many animals feed on them, including other species of os that live in the lake and rivers. They are believed to be closely related to the genus *Neos* and maybe even what *Neos* evolved from.

They have have synchronised spawning, where all individuals release sperm and eggs at the same time. Each female can produce up to 100 young which in a school of 30 000 can be up to 3 000 000 eggs. The eggs will float for several days before the young hatch, they are now 1 mm long and still have a yolk sack to absorb before they start feeding, that may be other small organisms, not fully developed eggs, others that haven't absorbed their yolk or phytoplankton. These will become adults in 2 months and continue living 2-4 years, males live generally shorter than females.

#### **Redspot characin os (Characios rubrummacula)**

**Creator:** M o t h/gonb

**Clade:** Os Oris, Ostrigonia.

**Habitat:** endemic to lake terasept.

**Size:** 5-6 cm.

**Diet:** herbivore.

**Reproduction:** spawning.

These small os travel in large schools which can have couple thousand individuals, largest of schools have 50 000 individuals and some even exceeding 100 000 individuals. These feed primarily on plants and mainly visible wit their blunt skulls and small sharp teeth which cut trough plant matter. They'll shred and tear off pieces of vegetation and even will eat dead plant matter. However they are quiet a common food source for many larger predators that swim in the waters and their main defence is by living in shallow water and staying near the bottom of the lake. Rarely they can be driven into a bait ball but their small and size allows them to escape and into the safety of rocks and some vegetation.

They mass spawn into 1 giant balls, and release everything at the same time and 1 individual can have 200 tiny eggs which float. They hatch within a week and begin eating tiny food particles until they reach a size of 2 mm and stay near the bottom in groups where they feed on dead plant matter and small plants that grow on rocks and around.

## **Species from the genus Vesperachios**

#### **Vesper os (Vesperachios vesperachios)**

Creator: M o t h, gonb

Clade: Os Oris, Ostrigonia

Habitat: Temperate rainforests of Terra septentrionis.

Size: usually 10-15 cm but in some locations up to 30 cm long

Diet: omnivore

Reproduction: eggs, spawning

Vesperachios is a highly unique species among the oses as it possesses 3 more eyes which are on top of it's head and help it spot predators. The 3 eyes weren't always there though and are believed to be a mutation which turned out to be highly useful and quiet quickly spread trough a population and had a larger survival chance of seeing predators from above. They feed on both plant matter and smaller animals, they mostly feed on smaller animals when they are abundant but when there's not alot they will swap their diet to a more herbivorous one.

They spawn when the climate is warm and have a unique way of doing so. A pair will jump to low overhanging vegetation that may be above the waters surface and lay eggs under the leaves. The male jumps and fertilises them. The eggs are covered in a thick mucus that keeps them humid and after 48 hours they hatch as tiny planktonic larvae and will fully grow up in 5 months. Size variation will depend on how big the water area where they live is, smaller waterways they will generally be 10 cm max while in larger rivers they can get up to 30 cm long but large specimins will travel trough shallow and smaller waters in order to get to different places which can make them vulnerable to predators.

## **Species from the genus *Spinosuos***

#### **Mangojaw stickle os (*Spinosuos mangomala*)**

**Creator:** M o t h/gonb

**Clade:** Os Oris, Ostrigonia.

**Habitat:** terra septentrionis, endemic to lake terasept.

**Size:** 5-6 cm long.

**Diet:** Carnivore, a micro carnivore.

**Reproduction:** spawning, eggs.

One of the more interesting of the Os species and belonging in their own family even. There have been countless fossils found of them near lake septentrionis and where the ocean used to be. These are believed to be the first os inhabitants to live on terra septentrionis. There are currently 2 species in their genus and about 5 more fossil species discovered but they went extinct. Largest fossil discovered of one is a 15 cm long skull nearby south of Terra septentrionis. Males are mostly solitary while females will travel in small groups.

Males will attempt to get as many females into their harem as possible for breeding. Males will usually pick a good and a secure spot where the young will be safe, under a rock works well, the male will dig out and use larger gravel bits to make a small entrance. Once the females have laid their eggs the male will fertilise them and start guarding. They'll fan their eggs with water so they can get oxygen and clean water in for their eggs. Females will usually lay up to 50 eggs which slowly expand as the juveniles inside grow. The male will guard them for 12 days without eating and just waving, however the male will still guard them until they reach a size of 3 mm. Then young will grow up in a month and live for a surprising 8 years and even more surprising, 15 years in captivity.

#### **Bigeyed stickle os (*Spinosuos magnuoculus*)**

**Creator**: M o t h/gonb

**Clade:** Os Oris, Ostrigonia.

**Habitat:** terra septentrionis, endemic to lake terasept.

**Size:** 15-20 cm long.

**Diet:** Carnivore, meat.

**Reproduction:** spawning, eggs.

Another species of the genus, which is still alive is the bigeyed stickle os. These have reduced armor and spines unlike their living relative, Spinosuos Mangomala. This reduction is most likely for speed. These os are truly solitary with them being rather aggressive to each other. They are highly nocturnal, hence their larger eyes and their size is also larger mostly due to them being nocturnal. They are also deep dwelling, passively swimming above rocky and sandy substrate of lake terasept. During day they'll be mostly deep down or hiding among rocks. However at night they swim in open water and in shallower places in search of food, anything that fits in their Jaws will be consumed, even their smaller Stickle os relative. But as light starts appearing they'll quickly head back into the cold deep, if trapped in shallow areas they'll quickly hide and wait until the next night.

Their breeding habits are mysterious but it's believed they breed similarly to the smaller *Spinosuos Mangomala*. Making dens and males guarding them ferociously. Their life cycle is also quiet unknown. The oldest specimin found in the wild was 11 years old yet how much longer they live is a mystery and needs more collecting and exploration to be done.