Strong-Jawed Emperor Vinestalker

Thanatomuraena ploíonerochýtis is a species of large Monocaudipinninid Caligobeloid Amphibian from the Najeete's marshes.
The animal lives in the medium to high depth zone, both found in open waters and among the long stalks of the aquatic plants covering the waters in vegetation.
The fin morphology of the second Anal in this species allows for sudden acceleration and even the ability to swim in reverse, making it perfectly adapted to its lifestyle among the vegetation.
The animal evolved as an ambush predator but since human colonization adapted to a more active lifestyle as anthropic activity brought many animals that were once found only in other depth zones into its habitat thanks to human settlements using stilt foundations, an optimal habitat for many species of the low depth zone.
The animal is perhaps most known for its ability to accelerate suddenly to very high speeds, bolting towards prey from its blind spot, often breaching water while doing so.
The animal colouration evolved to be optimal in camouflaging against the muddy sediment, swimming close to the riverbed of the massive water bodies it inhabits while remaining virtually invisible to possible prey looking from above.
Another noteworthy characteristic of the species is the extremely reduced Pectoral and Anal I fins, vestigial at this point, once used by the animal's ancestors for a different swim pattern and lifestyle.
The species is infamous for being very aggressive and extremely dangerous for Humans, going as far as attacking small boats, making short work of wooden hulls and easily capsizing other crafts, actively hunting for humans.
It is among the animals that have to be repelled with the use of Fire Tagumi venom darts, although it's one of the hardest to hit, given the ambushing strategy and acceleration it achieves.
The species is estimated to kill roughly 20 people a year, however the number may be much higher, given the nature of the marshes, as most people that disappear once they enter the deeper vegetation are never found.

Basic Information

Anatomy

• Head massive, armour segmented.

• Eye small compared to the head.

• Teeth of the distal dentary bone much larger than the others.

• Dorsal armour composed of ten large and rectangular Dorsal plates.

• Pectoral and Anal I fins vestigial.

• Dorsal fin spear shaped and moderately large.

• Anal II fin not coupled, running along the entirety of the second half of the abdomen right to the end of the Gill Tail.

• Gill Tail as long as the body, visibly thinner than the body.

• Gill Fan very small.

Genetics and Reproduction

Polyandrous species.
T. ploíonerochýtis mates in the spring, a few months before most other animals migrate to the open waters to mate, timing the hatching of the eggs with said event so that the young can have better chances at survival.
Females will assume a more active lifestyle during this time, swimming upstream and releasing a strong chemical signal that travels with the current to attract males to follow her to the mating site inside the deeper jungle.
Due to the location in which they mate, it's yet unknown how they select mates and which criteria are considered when selecting mating privileges.
After mating in the deep jungle, the animals will make their way downstream; males will stop along the way when they reach a suitable territory to call its hunting grounds while the females will reach the open waters further away from the rivers where most males hunt.
They'll lay their eggs upon arrival into the nesting area, which is also where the females usually live and humans settle.
The eggs hatch in early summer and the young will have to fare on their own from birth, at first feeding near the riverbeds and then progressively moving up in the water column as their prey changes in size.
Subadult specimens will have to be very attentive as to not get cannibalized by the adult females in the area.
When they're big enough they'll move upstream, driven away by the otherwise lethal competition with adult specimens; females will eventually return into the open waters when they're big enough, males will remain in upstream.

Growth Rate & Stages

Ontogenesis in the species very visible.
Hatchlings are born with developed Pectoral and Anal I fins, which helps them hunt during the first stage of life.
These fins wont grow alongside the body, however, forcing the animal to change lifestyle.
Loss of natal aculeus after seven months from birth.

Ecology and Habitats

Species found living near the riverbed or at medium depth.
It likes open spaces to hunt and medium-thick patches of vegetation to hide amongst.
Males often like more densely vegetated areas than females.

Dietary Needs and Habits

Predatory species ambushing medium to large-sized amphibians and land animals it finds swimming in its waters.
Young individuals change their diet while growing, eating everything from Grinning Pumpkinfishes to smaller conspecifics.
Infamous for its aggressiveness towards humans, females living near human settlements can attack boats to try and hunt the people sailing on them.

Biological Cycle

Periannial creature with no major dips in activity year-long.

Additional Information

Social Structure

Lonesome animal that doesn't tolerate Conspecifics outside of the mating season.
Even in mating season females won't tolerate one another, while males will co-exist with eachother.

Domestication

Absolutely impossible to domesticate, the specie is far too aggressive to be kept in captivity outside of certain public aquariums.
Possession of the species is banned worldwide, even though cases of people being found out in possession of one still happen and not always because they get reported for it.

Uses, Products & Exploitation

Humans tend to be preyed upon by the species more than use it themselves.
By many cultures regarded as a guardian, an almost mythological figure keeping foolish people from going deeper in the jungles, regarded by some as an embodiement of mother nature itself.

Geographic Origin and Distribution

Marshes of Najeete, from the Medium to High depth zone.

Perception and Sensory Capabilities

Average Eyesight, excellent echolocatory capabilities.

Symbiotic and Parasitic organisms

Afflicted by Intestinal Tube Worms and Fin-eating parasitosis.

Scientific Name

Eoichthyia; Tartarosomnia; Scutophalidae; Calvatopinnoidea; Caligobeloidea; Xenosteoglossidae ; Monocaudipinninae; Thanatomuraena; T. ploíonerochýtis

Lifespan

60 Years

Conservation Status

Least Concern: No measures under way to protect the species.
Population Trend: STABLE

Average Weight

500 kg to 3.5 tons

Average Length

5.5 m (male) , 7 m (female)

Body Tint, Colouring and Marking

Grey to mud-coloured armour.
Body green to mossy-green.
Dorsal, Pectoral and Anal I fins shaded lighter towards the tip, Anal II fin A bit darker towards the edge,
Tail striped in a lighter colour, single greyish band over the base of the Gill Fan.