Grovestalker
Splitting from its ancestor, the grovestalker has taken further steps to living on land, a trait it shares in common with its cousin the Tail-Walking Mudhopper. However, while the latter has almost completely abandoned the ocean, the grovestalker has still retained an adequate, though limited, capacity to swim, which it uses primarily for when they are either reproducing or moving about when not participating in their new lifestyle - an arboreal one. Unlike its ancestor, this species has the capacity to climb up the root systems of the Landfall Grove, Crystal Gazebo, and similar such species. It is able to accomplish this task with modifications that have evolved in its fins, which with jointed boney pseudo-claws, allow them to grip onto surfaces. Their tails bear a similar modification, with a covering of boney exoskeleton projecting from the lower portion of it, but this serves less for climbing and more so for helping to secure them in place onto surfaces, which can be a necessity during the monsoon season for those that are unable to find shelter higher within the tangling crystal overgrowth of their homes.
Similarly to its cousin, as an adult the grovestalker no longer relies on gills to breathe but instead relies entirely on directly taking in oxygen from the air. Said air is pulled in from the trio of nostrils on either side of the grovestalker's head, and then pushed through the former gill-chambers turned tubes. These lead directly into the lung-chambers situated on its back, whereupon oxygen is diffused into the blood-rich vessels located within as carbon dioxide is diffused out. The anterior pair of lung-chamber spiracles have sealed over with flesh, rendering them nonfunctional in this species, but the posterior pair remain and it is through them that the grovestalkers breath out. As such, the facial nostrils have effectively replaced the anterior spiracles in terms of function. Other than this, the grovestalker's respiratory system is comparable to that of its ancestors, especially within the larvae which are fully aquatic and must rely primarily upon their still retained gills for the first few weeks of their lives.
The diet of this species has now taken on a more herbivorous trend compared to that of its ancestor. Given its capacity for climbing, they can now more readily reach and consume the stickymosses they share their new habitat with, as well as several species of salt-resilient twistworms and, on rare occasions, wortopedes that failed to sense them in time to escape. To facilitate this new diet, the former fangs of its ancestor have evolved into thicker, flatter serrated plates situated in a shorter, heftier set of tentacle-jaws. They are now capable of shearing off chunks from larger specimens, as well as crushing and shredding smaller ones.
Some more curious specimens have attempted to gnaw on the crystal growths of their new homes, often times mistaking them for particularly well camouflaged species of twistworms. They do not gain much in the way of nutrition from this, primarily due to the fact that their tentacle-jaws simple aren't strong enough to sufficiently damage the crystal flora.
Compared to their ancestors, the boney exoskeletons of the grovestalkers are, while thinner and covered in a thin covering of keratin, more expansive in terms of how much of their bodies they cover, protect, and support via muscle attachments.