Stonepoles: Neotenic Trogolobites

In the underground rivers and lakes of siberian glowcaves, biomes that make up about 25% of the caves, bioluminescent fungi are completely absent and everything relies on gravity and rain to keep everything functioning. In these lakes, there are no fish, but there are stonepoles (caenura translucidus, transparent blind-frog), small neotenic tadpoles with a love of climbing.

Evolution

Stonepoles are descendants of the Common Frog. The Common frog first entered the caves in search of insects, the frogs can still be found near the entrance. The stonepoles were first descended from a long gone population found in the dark aquatic areas. Due to primarily being in the water for most of the time, the development of the frogs started to become stunted without a need for walking. In a short time the frogs evolve to live in a neotenic form for their whole lives.

As most trogolobites do, they completely lost their eyesight and pigmentation.

Biology

Stonepoles measure at about 7/8ths of an inch and live for about 1.5 years.

Stonepoles have no eyes. Instead they rely on chemoreceptors and hearing to navigate their way through the dark waterways. They have a strong tail and 2 small sticky nubs that were once legs on their hind quarters. These nubs are used to help climb waterfalls as well as give an extra boost while underwater. 

Stonepoles are omnivores and eat small crustaceans, whatever comes down to them from the caves, and in cases of starvation, their eggs or each other. They have a downward facing, suction cup mouth similar to a pleco fish.

When stonepoles breed, they lay a large clump of eggs under a rock and lay some unfertilized eggs for the young to eat. Not many stonepoles make it to adulthood but the ones that do stay as tadpoles, the only remnants of metamorphisis are the development of the nubs at maturity.

Behavior

Stonepoles have a tendency to climb waterfalls and swim upstream in search of food. When climbing waterfalls, they latch onto the rock with their mouth and push themselves up with their nubs.