Darwinauts
Darwinauts are various freshwater Nautstars found in Darwin’s rivers and watersheds. They live a similar lifestyle to their distant ancestor, the Wandering Shellstar, swimming near the river bed filtering out microbes and waste to consume. Similar to their counterparts in Wright, the Wright Nautstars, they help keep the waters clean and clear by consuming waste that would otherwise build up, and their commonly-fossilized shells add a colorful sparkle to the riverbeds.
Darwinauts come in brown, purple, emerald, silver, or red to camouflage against different substrate or flora. Living in water, they have little in the way of environmental adaptations apart from hibernating deep underwater in the winter to avoid freezing where relevant. The many species are difficult to distinguish from one another. Like their ancestor, they can retreat into their shells and reproduce with spore-like gametes.