Umbraworms

Splitting from their ancestor, the umbraworms have flourished and multiplied almost exponentially, spreading across the globe and dominating the vast expanses of the seafloor. Because of how rare mates can be in the deep waters of Sagan IV, hermaphroditism has become rampant in this genus, with species possessing distinctly separate genders being incredibly rare. Mobility is increased, and there is a clear distinction between adults and larvae, the latter of which are free-swimming and play an important role as zooplankton in the ocean depths.

All umbraworms are scavengers, a part of the cleaner crews of the seafloor, feeding upon whatever corpses manage to make their way down there. A decently sized corpse can attracts hundreds of individuals - consisting of well over a dozen species - all attracted there using highly sensitive chemoreceptors that pick up the minute particles of decay in the water. They will ravage these corpses, feasting on them and, depending on the species, focusing on specific parts of the body or burrowing into its internal organs. Mating is common at such morbid feasts, with pairs sharing gametes with one another before both release clouds of eggs into the water column. Depending on the size of the corpse, as well as the amount of umbraworms drawn to it, it can take several weeks to months for them to be stripped clean to the bone. In the periods of time between such meals, most species of umbraworms will enter periods of hibernation as they wait for their next meal.

Despite this scavenging lifestyle, umbraworms still retain their tiny but prominent claws. With them, they may finish off any small, dying sea life that is unable to escape their domain of the seafloor.

Most species of umbraworms only vary from one another slightly, though several different lineages have independently developed symbiotic relationships with various bioluminescent microorganisms, such as the many members of the glow detritis genus. They typically use them as a form of defense, shedding them to form an enveloping glowing cloud that clings to would-be attackers. In return, such microorganisms gain access to whatever food sources the umbraworms utilize, as well as some degree of protection.