Ancestor: Rainbow Trout
Evolved: 2 Myh from an intermediate between itself and the ancestor.
Extinct: Not yet
Location: East Catland South distributed across lowland freshwater habitats.
Viable Habitat: Warm, plant-choked wetlands, rivers and shallow lakes. Intolerant of freezing winters.
Size: Largest Species: Grows up to 2 metres long, Smallest species: Grows up to 1.2 metre long.
Dietary Needs: Newly hatched fish start out omnivorous with a mixed diet of microbial algae and near-microscopic animal life. They slowly move up to bigger and bigger prey and become fully carnivorous, consuming aquatic and land prey of all kinds as long as it's small enough to swallow. Fully grown adults can catch and eat small rabbits.
Life Cycle: In the cool winter adults migrate to the place of their own hatching to spawn. Unlike their ancestors they don't always move upstream to spawn. Spawning is a competitive ordeal, with males employing different strategies to try and get in on the act of spawning, and females taking a more strictly ritualistic and selective approach.
The spawn hatch in about a month and are left to their own survival. These fish are an r-selected species to the extreme. Adults can live for decades, but might not produce offspring that survive to adulthood on every year despite producing (or fertilizing) 1,000 eggs. Variation in weather in comparison to previous years might cause some spawning grounds to dry out in a particularly hot temperate summer, killing any young fish trying to survive there. Other times the competition to survive is just too great, and the batch of offspring was just not strong enough. There are plenty of reasons why all 1,000 young fish might not be alive by the next year. As long as this is offset by more successful years where a good portion of the young fish survived to adulthood, then the parent can still be reasonably successful.
Other: This is a freshwater fish. Although it's ancestors had a saltwater morph, this descendant does not. It still migrates downstream before the dry season in the few areas of it's range that get a significant enough dry season, and it can tolerate brackish water in some wetlands, but never enters the sea.
Although their eyesight is generally fine in clear water, they are at an advantage in murky, brown, water-choked water even though such conditions limit vision. Their long bodies have a sensitive lateral line that can pick up tiny vibrations, and their strong serpentine body can move and react quickly. Sensing where the vibrations are coming from and what kind, they determine unconsciously if it's worth responding to at all. They can also weakly detect the electromagnetic field of other organisms along their bodies via disturbances in their own field. Having a long body spread out and wound loosely about gives them more sensory range and more chance of detecting prey.
If the source of the vibrations or electromagnetic disturbance turns out to be danger, that danger gets a nasty bite when the eeltrout instinctively reacts and might hopefully be startled enough for the eeltrout to get away.