Serina: Tree Gup

When snarks rafted to the continent of Serinaustra ten million years ago, they, and many new immigrants to the defrosting lands, discovered a slate wiped clean, with endless food, no competition, and a balmy climate. It was a perfect petri dish from which the small populations that had been lucky enough to be carried by the sea to such prosperity could rapidly grow in number. Dozens became hundreds, hundreds became thousands, thousands became millions. Two founder species, the prismatic gupgop and the speckled gupgop, became over three-hundred species over countless millennia. What fuelled their massive diversification was not merely lack of competition, but the variety of habitats which developed alongside them as plant life colonized the surface of Serinaustra. In the evolutionary blink of an eye, forests began carpeting the continent, and following them were so many forest-dwelling animals. To the gups, this was uncharted territory; it had been millions of years since the last snarks had encountered groves of towering vegetation. But if their diversity under the waves had not already proven, snarks are nothing if not willing to adapt.

Clambering amongst the boughs of the fast-growing and highly abundant dancing trees is one of Serina's most peculiar arboreal fauna. Growing only about a foot long, it crawls across the trunks and branches, with back and forth shuffling like a lizard, hugging its flattened body close to the surface and using stick pad-like fingers on its four appendages to cling to the bark. Its mottled dark and pale body and numerous fleshy lobes make the outline of its body difficult to see while it lies still upon the algae and lichen-encrusted trees, with only its stalked eyes and sensitive feelers twitching to detect food and foe alike. Often it seems nearly as immobile as the tree trunks it sits upon, until it suddenly leaps from branch to branch, darts with swift jolts up and down the canopy in erratic and unpredictable spurts, or launches its projectile proboscis at a small invertebrate that got too close. It was not long ago that this animal's ancestors scurried in the leaf litter far below, but the flitting of flying insects far above was an enticing enough lure for some of them to make a living beyond the undergrowth. This is a gup which has grown slimmer, faster, and more agile to live in a more precarious world.

Although it evolved from a poison ancestor that brightly advertised its toxicity, the tree gup has long since lost this defence. As it ventured in land, it could not longer rely on its diet to provide its toxins, and instead turned to more practical and mundane camouflage to keep itself protected. Like most snarks, it can alter the hues of its skin to darken and lighten itself, or make the spots and stripes stronger or more faded as needed to better match its surroundings. When cornered by a threat, it can also pull out a spectacular last-resort maneuver to deftly dodge its pursuer; the gup peels away, pushing off with its tail and enters a domain previously unknown to mollusc-kind: the air. Spreading its four appendages out, the fleshy lobes provide a crude lifting surface, carrying the gastropod across the sky for a distance of up to two-hundred feet. Its sticky finger pads allow it to immediately latch onto any branch or tree trunk it lands on, but its small size and soft body prevents any chance of serious injury from a botched landing either way.

Tree gups have adapted so well to their new environment that it is theoretically possible for one to never once touch the ground from birth to death. When this rare event does occur, the gup is very quick to find the nearest tree and starts climbing back up; the modifications granted by natural selection to better suit its arboreal life have now rendered it more cumbersome on the forest floor. Even courting and mating occurs in the trees; because they are so well camouflaged,  tree gups must rely on the auditory signals of their mating calls to find one another from a distance, making their ability to pick out the distinct vibrational wavelengths from other sounds in the forest far more attuned. Their feelers have many minute hair-like filaments which allow them to pick out sounds from the air similar to many insects, rather than simply relying on vibrations travelling through the ground. This is an ability that can also mean the difference between life or death when detecting the soft flutter of a wingbeat from an approaching predator tribbat or bird-of-prey homing in.