Tjaetsiimaj

Also known as 'Twilight Hunter', 'Cave Pterac'

Public sentientologic record
Property of the Royal Atheneum of Hövnís, Eörpe

The tjaetsiimaj is the most well-known and thoroughly studies species on Biegjun, catching the interest of the present Suszukoro researchers early on due to its peculiar behavior and its abundant appearances in bieggjan mythos and stories.

Etymology & Definition

The origin of the native’s name of the species is unclear, as is its exact meaning. It’s believed to belong to an older gjevasudit language and may be a composite word made out of the roots ‘tjaets’, ‘siima’, and ‘aju’.
'Aju' is a pronoun for ‘I’ and ‘me’. ‘Tjaets’ is speculated to be related to ‘tjakha’ which translates to ‘stone’ or ‘rock’. It’s thus possible ‘tjaets’ is an older word for ‘cave’, ‘burrow’, or ‘hole’. The meaning of ‘siima’ is still unclear but could be related to ‘cold’ or ‘coldness’.
In some tribes, the name Tjaetsiimaj and the term for evil spirits, Oniijavat, are used interchangeably.

History

Current Day

The tjaetsiimaj is considered the most aggressive and dangerous predator found on Biegjun, despite its appearance on the surface is heavily dependent on seasonality. They appear the primary natural controlling measure against overpopulation as their seasonal swarming typically leads to drastic reduction in numbers among both herbivorous and other carnivorous species. Their only natural enemy is the highly specialized, lepticidan mursamuul.

Habitat & Population

The tjaetsiimaj’s primary habitat is found below the surface, in large subterrain cave systems and grottos beneath most of the planet’s larger mountain ranges. Several underground rivers and lakes have their own ecosystems featuring a surprisingly varied amount of reptilian, amphibian, and piscine herbivores living off of algae, grasses, ferns, mushrooms, seagrasses, and kelps. The tjaetsiimaj appear to be the main predator of these ecosystems, only competing for food with two aquatic-bound carnivores.
They appear to follow a predicable sharp rise and slow decline in population based on their seasonal mating patterns, but at average seem unusually numerous compared to most other predators found on Biegjun. It could be that they’re outcompeting other extant and extinct predators, which would also explain the relative lack of variation in carnivorous species.
They live in dark and damp areas that has access to pools of water with at least a portion containing silt or mud. Most of the subterrain habitats are cold but not frigid, but they can also be found living in warmer temperatures. They actively avoid sunlight and arid environments.

Geographic Origin

Most entrances to tjaetsiimaj subterrain habitats are found along the largest mountain chains, the Aapimosii and Kuusamaj. These are commonly natural cave openings and river outlets.

Galactic Distribution

The tjaetsiimaj are exclusive to the planet of Biegjun, and export of the animal dead or alive is strictly forbidden under the Suszukoro Reserve Zone policies.

Taxological Data

Status

Least Concern (LD)

Designation

Sentient

Aggression

Extreme

Numerus

One Tjaetsiimaj
Many Tjaetsiimaj

Binomen

Scutispinaensis Litusvenoris

Ancestry

Unknown

Descendants

None known

Variations

None known

Biological Data

Composition

Organic

Biochemistry

Carbon

Morphology

Pteran

Metamorphality

Bitroph

Hybritism

Pedigree

Respiration

Type I Solyxide-Base

Diet

Carnivorous

Locomotion

Bipedal
Crawling
Flying
Swimming

Expected Lifespan

15 years

Average Height

40cm

Average Length

130cm

Average Weight

40kg

Natural Habitat

Subterrain
Wet/Dry Climate

Homeworld

Biegjun

Verse

Realverse
The Rosepetal

Biology

Morphology

Tadpole

Prior to metamorphosis into adult form, the tjaetsiimaj live as aquatic tadpoles. Three external gills with soft, feather-like frills are used for underwater breathing. Newly hatched tadpoles are roughly 30cm in length and weight around 2kg.
They have streamlined bodies and a triangular head with a thin, pointed snout. Two sets of pointed cartilage extremeties extend along the lateral sides and are connected together with a thin membrane that serve as its main means of underwater propulsion. The tadpoles feature the same gill-like nasal openings on the top of the head as the adult specimens, and rely on them as well as their developed sense of touch for orientation.

Adult

The mature tjaetsiimaj are pteran-form, ectothermic, amphibious animals that perpetually continue to grow in size throughout their lives. The average life span is 15 years, by which time most specimens range between 130-150cm in length from nose to tail, with a wingspan between 250-300cm, and weight around 35-45kg. The females are smaller than the males and have shorter crests.
A wedge-shaped, heavy head with four crests connects to a muscular neck. The body is oddly triangular, the ventral side being close to wedge-shaped, and the dorsal side is more rounded. They only feature a pair of front legs to use for locomotion, using the head and tail for balance during terrestrial movement.
The front limbs are positioned laterally close to the base of the neck and sprawling out on the sides of the body and during terrestrial locomotion typically won’t lift it more than is necessary to avoid the underside from touching the surface. Two fingers serve as gripping appendages with curved claws suitable for scaling rough, vertical surfaces. The two outer fingers see significant extension to support the capacity to fly. A thin membrane is stretched between all fingers, connects to the skin of the body just below the lateral ‘flaps’, and continues to extend along the entire length of the tail. The membrane is supported with several pairs of spines made from cartilage.
A long and powerful tail serve as an off-balance for the large head during terrestrial movement, providing extra lifting power during flight, and is used as propulsion when swimming.

by Nimin N.

Anatomy & Physiology

The tjaetsiimaj’s many physiological and anatomical adaptions is likely a large factor in it becoming the most widespread and successful apex predator on Biegjun.

Skeleton

The skeletal structure of the tjaetsiimaj shares several characteristics with other pteran-form, flight-capable species such as a keeled breastbone and hollow bones. The skeleton is unusually light-weight and extremely strong, very closely resembling graphene in structure.
Similar to the skeletons of many other Biegjun species it’s semi-conductive, and also appear to have a higher-than-expected thermal conductivity.

Calefaction Pulp

The hollowing of the bones appears to not be constant, as some specimens caught in their subterrain habitats featured a marrow-replacement substance in any number of their bones. It appears to be in a jelly-like state upon formation and after a time dries to a pulp. The substance is broken down and absorbed by the body in preparation for flight.
Specimens caught during surface swarming entirely lacked it. The substance has proven to be very effective at absorbing and storing heat, and combined with the thermal conductivity of their skeleton might be an adaptive mechanism to maintain body temperature for longer in cold environments.

by Nimin N.

Helmet

The tjaetsiimaj’s head is covered by a thin exoskeletal shell that’s connected to the skull with stems extending from the base of its four crests. The snout forms a long, sharp beak with the mouth appearing as a lining on the inside. It's construction and the alignment of the teeth lead to an inability to fully close the mouth. During diving, water is stopped from entering the esophagus by a ring of muscular tissue and the tongue forming an airtight ‘lid’.
The helmet feature four symmetrically aligned crests, with males' being more impressive in size. Two of the crests are laterally aligned between the mouth’s beginning and the back edge of the helmet. The other two crests are ventral- and dorsally aligned and begin all the way at the tip of the beak and end at the back edge of the helmet. The dorsal crest is more than twice the length of the ventral, while the ventral crest is thicker by the base. All four crests curve backward and taper off into a half-crescent shape.
The crests have several functions: their sharpened sides aid in aerial and aquatic hunting, where they ram prey head-first and then tear off bite-sized pieces with their razor-like teeth. Males will use them to compete for female attention during the mating season, and females appear to be more attracted to males with larger crests. The dorsal crest also functions as an extension of the olfactory organ and hosts two hollowed out spaces connected to the large nasal openings situated on the sides of the head. You can read more about their sense of smell and the olfactory organ under Sensory Capabilities below.

Neurology

The tjaetsiimaj utilize the higher than usual conductivity of their skeleton by having the central nervous system form a thin mesh along surface of the skeleton. The peripheral nervous system branches out from this mesh through countless of individual axons in order to connect it with all limbs and organs. This has led to a heightened sense of touch that serve as their primary means of orientation, which is more closely described under Sensory Capabilities below.

Respiratory System

Tadpoles are exclusively aquatic and utilize three pairs of external gill stalks lined with filaments for respiration. These gills are dropped upon metamorphosis.
Adult specimens observe primarily cutaneous respiration, where they exchange gas across the skin and the tissues lining their mouths. Scale-like ‘flaps’ made from cartilage discs covered with skin increases the available surface and helps increase rate of Respiration. During flight and dives these flaps are typically pressed flat against the body.
They can also, if necessary, utilize buccal pumping to provide oxygen to their lungs. This is usually done in a two-stroke manner that pumps air from the mouth to the lungs, and in a four-stroke manner that reverses the pathway through compression force.

Skin, Tissue & Blood

The tjaetsiimaj’s skin is permeable to water, serves as a respiratory membrane, and is well-supplied with glands. The majority of the glands discharge a mucus that helps keeping the skin moist with is important for both respiration and thermoregulation in the species. It also aids in preventing bacterial and mold infections, reduces friction when swimming and makes it slippery and more difficult to catch for other predators.

Both sexes observe similar a coloration ranging from dark indigo to ultramarine blue depending of region, with a lighter underside.
During mating season, the males are far more colorful and feature biofluorescent patterning in bright blue and green colors. These colors appear to be a byproduct from a chemical reaction that occurs when secretions from glands situated by the central-dorsal thorns are exposed to air. The secretions contain pheromones that along with physical displays are used to attract females.

Sensory Capabilities

The tjaetsiimaj only feature three different senses: smell, touch, and taste. All specimens lack aural and optical organs and are thus both deaf and blind.

Smell

Their most developed sense is smell and it also appear to be their primary means of locating prey. The large opening on either side of the helmet, filled with gill-like filaments, serve as the nasal opening. These nasal openings are connected directly to a large olfactory organ that take up both part of the skull cavity and also occupies a pair of hollows in its dorsal crest.
The olfactory organ is incredibly highly developed and sensitive, and they are capable of sensing very low amounts of different chemicals in both air and water.

Touch

The composition of its nervous system has given the tjaetsiimaj a well-developed sense of touch that’s capable of sensing certain sound waves, physical vibrations, and magnetic fields. It’s theorized that they use the planet’s magnetic field to orient themselves.
They also seem capable of discerning light levels, though exactly how isn’t yet known. At first it was thought heat generation or UV-levels played a part, but the tjaetsiimaj have been found to flee from mechanically powered lamps as well.

Taste

Of the three senses, their sense of smell is the least developed and appear to mostly serve as a means of – together with smell – discern matters that aren’t considered edible.
The tjaetsiimaj won’t eat carrion and appear to avoid the smell of decaying or rotting meat if possible. There are also certain other smells and tastes that repel them.

Genetics

Life Cycle

Tjaetsiimaj has an average life span of 15 years, though could possibly live much longer. There are no known specimens to date that have died from age and instead it appears to be extremely common for them to eventually either fall prey to each other or to other predators.

Reproduction

The tjaetsiimaj reproduce through internal fertilization, where a male deposits its sperm directly into a female’s cloaca. The sperm will be stored in a spermatheca, a chamber in the roof of the cloaca, until the female has returned to its underground habitat and found a suitable pond of water to spawn eggs inside.
A single female typically lay 20-30 eggs in an underwater crevice and guards them until they hatch about 50 days later. Once hatched, the female leaves and the tadpoles fend for themselves.

Growth Rate & Stages

The tadpoles’ growth is directly relative to its consumption of food, and feeding will remain its sole concern up until reaching a length of roughly 50-60cm. If food is abundant, this typically takes about six months. While normally not cannibalistic, they will resort to eating their own kind if food is too scarce. Otherwise they are exclusive piscivores and live off of small fishes and shrimps. Once a tadpole is sufficiently sized, they’ll find a location with lots of silt or mud to submerse in and go through metamorphosis into their adult form.
During the metamorphic process, which typically takes two weeks, a tadpole undergoes several physiological changes such as having the external gills grow back into the body while the helmet forms around its head and developing a pair of forelimbs for climbing and flight. Once the metamorphosis is complete the new adult specimen crawls out of the water to primarily live on land.
After metamorphosis the tjaetsiimaj have a much more varied diet consisting of fish, crustacean, meat, and insects. They are very indiscriminate feeders and there’s only a rare few species they’re known to avoid, including the surface-dwelling mursamuul as well as a couple of poisonous amphibians and insects. The mursamuul’s musk is a particularly well-known tjaetsiimaj repellent. It'll take roughly another year for the young, adult-form tjaetsiimaj to reach sexual maturity.

Behavior

Social Structure

In their subterrain habitat, newly hatched and young tjaetsiimaj are often found living solitary lives up until reaching mature age. Once having partaken in, and survived, their first mating season they’ll typically integrate into any of the pre-existing colonies after they all retreat back into the subterrain habitat.
A colony can host anywhere between 10 and 400 individuals depending on food source availability. Its normal for colonies to hunt in large groups, either the entire colony at once or in smaller subgroups. They also tend to observe synchronized cycles of activity and rest, with the entire colony clumping together along a vertical surface or inside a crevice for shared safety and warmth.

Pheromone-Mixing

Glands located along the tails produce a pheromone that mix into the mucus covering their skin. By rubbing tails regularly, the pheromonal scents of a colony’s individuals mix together and make it easier for a colony to identify individuals as belonging to their colony.
This makes it difficult for outside tjaetsiimaj to integrate into a colony unless taking advantage of the chaotic conditions arising during the mating seasons. While a swarm segregates back into their respective colonies, solitary individuals can successfully sneak in and manage to mix their own pheromones with enough colony individuals to become accepted in. In all other circumstances, tjaetsiimaj identified as not belonging to the colony are typically attacked and eaten.

Culling

Tjaetsiimaj colonies appear prone to removing individuals from their numbers that are sick, wounded, or otherwise weak. In most cases this is done through cannibalization, where the individual is attacked by a part of or the whole colony and eaten. It’s rare for a singled out individual to escape, and if it does it’s usually only a question of time before it’s found again by either its former colony or another predator.

Communication

The tjaetsiimaj are thought to communicate using physical touch and pheromones.

Mating Patterns

The tjaetsiimaj only mate during the late half of the normal winter season. Due to the cyclical nature of the planet’s seasons, normal winter season occur on a yearly basis for roughly 13-16 years in a row before being replaced by the bright winter season for the following 34-37 years.
Males and females, if sufficiently gorged from the first half of the season’s feeding frenzy, will shift their focus from hunting to finding suitable partners to breed with once midwinter has passed and the days begin to grow brighter again. It’s not uncommon for the sexually mature tjaetsiimaj to gather in massive swarms above the entrances to their normal habitats and commit to explosive group breeding. The mating season will last either until the days grow too bright for them to stay on the surface, or until the swarm runs out of females. On average, this can be between 10-12 days.
The males of these swarms typically begin to secrete a pheromone that’s considered enticing to females and may heighten their willingness to mate. This secretion is what gives the males their bright coloration during this period, which appear to be a side effect from a chemical reaction occurring as its exposed to air, and the scent it gives off also uniquely identifies that particular male. They will viciously compete for the attention of as many females as possible, with wounding and killing rivals being common.
It’s exclusively the female’s decision of whom to partner with and they appear to generally favor larger males featuring impressive crests. Once a female has picked a mate, it’ll do several flybys to touch the chosen partner and have its pheromonal secretions rubbed onto her body. The female will then make a sharp rise, high up in the air, hopefully followed by the male she picked.
Once sufficiently far up in the air, they latch onto each other, and mate while free falling toward the ground. Mating relatively quick and typically concluded well before being close to hitting the ground, and afterward the male rejoins the swarm in hopes of getting to mate with additional females, while the newly fertilized female retreats to the underground habitat.

Interspecies Relations

The tjaetsiimaj is a major predator on Biegjun, sharing spot as the planet’s apex together with the muursamul and the tursatjek. As far as is known, these other two predators - along with a few insects - are the only ones known to not be part of the tjaetsiimaj’s diet. Rather, the tjaetsiimaj have proven to be common parts of these two’s diets.
The muursamul have adapted to nocturnal hunting during the seasons that have twilight hours and specialize at catching swarming tjaetsiimaj through high leaps into the air. The tursatjek is a more opportunistic feeder that observes clear advantages over the tjaetsiimaj within its aquatic environment. It’s not uncommon for younger tursatjek to find their way into the subterrain rivers and lakes, and feed on both tadpoles and adults that enter the water.

The shadow dove from the sky and Amatolja held their breath. They thanked Jusokyahka for having painted the Hyssna so they could see it coming. It’s beak was like the point of a spear, aimed straight at their chest.
They tightly held the pot of murkrot prepared the day before, but still feared it’d slip out of their hands. It was one of many doubts that plagued their mind while waiting for the exact right moment. That they’d fumble or drop it. Or worse, that the murkrot wouldn’t work at all.

— From the myth 'Soha Oppalil Amatolja'

Tjaetsiimaj & the Bieggjan

The natives of Biegjun hold a deep-seated fear for the tjaetsiimaj, and many tribes even synonymizes the animal with the evil spirits of their mythology called Oniijavat. This likely stem from a common belief that these spirits tend to favor tjaetsiimaj as “nests”.
Many heroic stories tend to feature tjaetsiimaj as a villainous entity, often driven by the deity-beast Seempola, that the story’s hero must outsmart and defeat to save themselves and their family. The most famous of them is the ‘Soha Oppalil Amatolja’ (nonlit. ‘The Saga of Amatolja’) which is told in numerous tribes, many of them as well claiming it originated from them.
It’s very likely that the tjaetsiimaj played a part in why the bieggjan chose to be primarily nomadic. Many tribes’ trails follow the migrations of larger herbivores, such as the hukhayja, and can be up to a year long in one direction. It’s been ascertained that their travel patterns are very dependent on the seasons and that they keep track of passing time in order to predict weather and seasonal changes. While they can’t avoid all twilight hours, the bieggjan appear to have learnt how to plan their trails in order to not be caught living in a region that’s expecting a normal winter season.