Burrowyrm

Splitting from its ancestor, the burrowyrms have spread deeper inland into Vivus and have even gained ground in Darwin itself. While their ancestors along the cold, polar coasts of the continent continue to dwindle in population, the burrowyrms have instead gone on to thrive, having evolved better adaptations to the cold that serve to compliment their semi-subterranean lifestyle. Filling out the niche of a small predator, they help to keep the populations of various small fauna in check, and are in turn kept in check by various larger predators.

One of the most prominent features this species has evolved is their bright colors, a highly visible trait which they utilize to warn off potential predators. The reason for this of their mildly venomous bite which has recently evolved. This poison does not involve the usage of poison sacs connected to fangs and is instead produced by the salivary glands and coats the teeth. While said poison is deadly to small prey items, paralyzing them outright, it can still cause a painful burning sensation for anything larger than 20 centimeters long. Another noticeable feature is the numerous thorn-like spines that form rows along their backs. Anchored in the chainmail-like formation of bony nodules located just beneath the skin, each spine possesses several muscular attachments, allowing them to be flexed about to a limited degree. While individually this achieves little, when done en masse this allows better digging through both leaf litter and soil, especially with the aid of their spade-like specialized tooth.

For most of the colder parts of the year, the habitats that burrowyrms call home are distinctly barren of them. This is because during these times they will burrow several meters underground in small hollows they have dug out, sleeping away the winter in a state of brumation. They await for the return of warm weather, for only that - or prolonged exposure to the body heat of another organism - is what is capable of awakening them from their slumber. In fact, so deep is this state of dormancy that they remain utterly motionless towards most external stimuli, and will not even react to being dug up, at least not immediately so. Once spring has returned, however, they will begin to eagerly return to the surface and gorge themselves on a wide variety of small prey items, utilizing their venomous saliva to incapacitate them so that they may be crushed in their jaws and then devoured.

Besides the seasonal gorging that burrowyrms undergo with the arrival of warm weather, so too do they seek out mates. Intertwining themselves with one another, a mated pair will remain in such a position for hours at a time, after which they will go their separate ways. Burrowyrms choose a new partner every year over their ten year lifespan, and each mating typically produces several tiny squirming offspring for whom the parents show no parental care. The young will need to rely on their venomous saliva and capacity to burrow if they are to survive the numerous predators that would otherwise make a quick meal of such small offspring.

Because of the change in their diet towards small, mouth-sized prey, the size of several of their fangs - outside the large, modified one - have reduced significantly, to the point where they are no longer exposed when their mouths are closed, much like the majority of their teeth.