The polar basin is Serina's largest inland body of water, and throughout the hothouse period, it has remained fairly consistent in its size. By 290 million years P.E this vast freshwater lake, or inland sea, is also fairly ancient. Biodiversity is remarkable within its water, little-disturbed for 20 million years. The basin is so large a biome that it directly influences the landscape surrounding it, creating additional biomes unique from itself. To the west, the nightforest grows trees taller than any before them, thanks to the water which evaporates from the basin, forming clouds that hydrate their tallest branches. To the south, the basin overflows its borders and floods, forming what is now the largest contiguous wetland on Serina, the upperglades, including the flood forest. And to the east, the direction the primary winds blow in the northern hemisphere, the basin sits against an environment that is startlingly bizarre and out of place in the hothouse world. A vast field of towering, shifting sand dunes, some over 3,000 feet high. It stretches for hundreds of miles along the eastern shore of the basin, a desert landscape produced by 20 million years of washed-up, wind-blown sand from the basin's beaches. This ancient biome is as old as the basin itself, and has grown consistently in size over time from a series of small shoreline hills to veritable mountains of shifting sand, some over 75 miles inland. Many grains of basin sediment ultimately blow much further away in the wind, fertilizing landscapes hundreds or even thousands of miles away, sometimes even out to sea.
This desert is not dry. It rains frequently at this latitude - and at all latitudes, and the humidity never falls too low. Yet the sand, always blowing loose in the wind, not only drains away all water it receives in a short time, but greatly limits the growth of plant life over its surfaces by burying them beneath its shifting dunes. This vast dune field, at the top of the hothouse world colored green from coast to coast, and on the shore of a vast freshwater sea, can be seen from a great distance, a mountain range of pale sand that rises above the forest and the trees.
This is a raindesert, a phenomenon that has never occurred before the hothouse.
The hyperborean raindesert of northern Serinarcta is one of two such regions worldwide, the other being the much less extensive dune fields that lie along the shore of Serinaustra's great blue salt lake, which are known as the saltspray sands. The formation of such a habitat is very rare, and occurs only along the leeward side of very large inland lakes with relatively shallow sandy substrates. The raindesert formed by the polar basin is especially vast because the lake is so large that it is permanently cooler than the surrounding air, and so is a constant low-pressure system. Wind blows in from all sides at all times and is then gradually carried east by the primary air currents of the atmosphere, producing eastward waves that bring sediment in even from great depths. The loss of sediment, from washing ashore and piling into dunes over time, has increased its depth significantly. During summer, the basin warms under the long hours of daylight, and the temperature difference becomes minor; winds die down, and for a few months the water is calm, allowing plant life to cover its shores. In fall, the water begins to cool without the sun's radiant heat, and the winds pick up. Winter is a time of stormsurges, massive waves and powerful wind gusts, and most dune-building activity occurs over winter. This effect is weaker in the great blue salt lake than in the basin because, being closer to the equator, this lake does not experience polar winter, and never sees the wind speeds that the basin experiences annually. One inland sea which does not produce a dune system at all is the Centralian Sea, as it has a rocky substrate rather than a sandy one. While that sea is oxygenated at all depths year-round due to a combination of deepwater currents produced by the outlets of groundwater rivers and from surface winds, the polar basin is circulated purely by wind. As such, it becomes anoxic at greater depths during the summer, when those winds weaken.
While the polar basin is at its most productive under the long days of summer, the raindesert is then at its least hospitable. Without nights to allow the dunes to cool, and with minimal vegetation to shade it due to the constantly shifting sands often burying plant life, the raindesert heats up like a furnace beneath the sun. It stores vast amounts of energy as heat which can rise air temperatures above the dunes to over 115 degrees Fahrenheit, some 35 degrees above average air temperatures of surrounding regions and most of the hothouse world. Desert life becomes efficient at getting rid of excess heat and may retire below ground during the hottest time of year; many species migrate through the desert and leave seasonally. Though the unique challenges posed by this desert have led many species to become specifically adapted to it, and not found anywhere else, due to the close proximity of the desert to the polar basin, other unexpected animals can also be seen to venture inland, especially if they smell a possible meal, and many seabirds and tribbats which hunt on the water fly inland to the less populated dunes to rear their young.
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Several species depicted in the landscape above have already been explored in adjacent biomes, such as the polar basin and centralian sea, or in dioramas (see seedsnatchers, flameflowers, and firefinches.) A variety of other species found in this globally rare habitat are presented below.
The scissorsprink is an endemic species that only occurs only in the hyperborean raindesert. It is the smallest sawjaw, weighing just one pound. Closest related to the springler, this springheel descendant is endemic to the hyperborean raindesert. Scissorspinks have long, fur-lined digits adapted to support their weight on loose, wind-blown substrates, and are evolved to hop across the dunes, where they hunt for insects and small vertebrates like seedsnatcher molodonts and lumpuses. Scissorsprinks catch prey by pouncing upon it and snatching it in their long, very sharp jaws, which are slightly extendible and resemble a set of scissors. They don't overlap when biting, however, but rather close together with interlocking teeth cusps and so trap animals in a vice-like grip. Each cusp on each tooth is serrated - a mini steak knife, and able to chop up their victims with a few rapid snaps, so that the pieces can be easily swallowed whole.
These tiny sawjaws make their homes in tussocks of dune grasses, amongst the roots of rare trees, or below large boulders - relatively stable landmarks in the landscape. They dig out shallow burrows for shelter from predators and to rear their young, though have little need to avoid extremes of temperature, as the desert is neither extremely hot, nor ever cold. Both sexes of scissorsprink have elongated ears ending in fluffy white hair tufts; these have no use in catching food, as in their close relatives, but are instead used for social communication. Their great size allows individuals to see others on the relatively open sand dunes from far away, and their mobility allows a simple gestural language to exist, communicating intent. The ears are also used to touch one another - a gesture of affection between pairs or toward offspring, and a less risky way to scent a rival at a distance, to check their intentions. Better to have an ear bitten than the face - and if lost, the ear tips regenerate over time, being made up only of cartilage.
Scissorsprinks usually live in groups based on a pair and their offspring, but offspring can take a long time to disperse, so that a clan may be comprised of a pair, several mature offspring whose reproduction is inhibited by pheromones produced by the adults, and one or two younger litters still dependent on more active parental care. Older siblings help care for younger ones, and occasionally larger groups of these animals will hunt together cooperatively, catching an animal they could not kill alone, often bigger than themselves - this is not common among springheels, which are usually solitary hunters, but harks back to their ancestry as fierce pack hunters of thorngrazers in the early hothouse. To kill such prey, the sprinks take turns striking at its backside while others goad the animal into turning to face them, until the animal is weakened by bloodloss or shock, and they can begin dismembering it and storing it piecemeal back at the den. Despite allowing a greater success rate versus hunting smaller prey alone, cooperative hunting like this is infrequent, and rarely seen outside temporarily large family units. This may be because if groups become too large, they attract more attention from larger carnivores that may kill them, or simply take their food, so that by staying more widely spread out most of the time, the species ultimately survives best.
The dune foxhopper is a locally common, though shy and rarely seen, species of foxtrotter native to polar Serinarcta, particularly the sand dunes of the hyperborean raindesert, but not exclusively; a few scattered populations also exist in coastal areas around the polar basin. It is not generally present in the night forest, nor in the upperglades, though it is sometimes found living along large rivers with wide, sandy riverbanks as far as 500 miles south of the basin. A species of foxhopper belonging to a genus of relatively generalized small predators, its closest relatives are native to upland grasslands in northwest and central Serinarcta. Adults are fairly small, weighing no more than twelve pounds - similar to a cat, though somewhat taller. Dune foxhoppers are strongly associated with sandy places, not necessarily only in this desert, but usually so. They favor them forsituating their dens, which are always positioned at an elevation above surrounding land as a defense against flooding. There is no place less likely to flood than the tops of sand dunes, and dune foxhoppers often dig out their homes very high up on old, stable dunes, burrowing to a depth where the sand is damp and compacted; even so, the loose substrate holds dens poorly, and so they are rarely more than small chambers with only one entrance. Groups are the normal social unit for this species, ranging from two to five adults that may or may not be related, plus multiple litters of pups; all adults feed and protect all pups, and multiple females are generally permitted to breed within a group, as the dominance hierarchies between them are not strongly defined.
This species of foxtrotter is very non-aggressive, having very amicable social relations and a wide ranger of affiliation behaviors that help alleviate tension and maintain group cohesion. Social grooming is very common, and reduces stress for both parties while increasing social bonds. When threatened by a predator their instinct is to run, rather than fight, which they can do at great speed even over loose sand thanks to their small size and toes which splay out with each step. Though they are adapted to desert-like conditions, this foxtrotter has smaller paws than many earlier foxtrotters, indicating its adaptation to a sandy environment where large paws might help better distribute weight is quite recent from ancestors living over more stable ground. The dune foxhopper seems able to compensate well by adopting an almost monopedal hopping locomotion when moving quickly, in which the entire hind foot, up to the ankle, strikes the sand with every leap, providing a long, snowshoe-like surface that bounces off the sand and allows a remarkably fast escape, especially when the animal flees down the slope of a high dune.
Dune foxhoppers have small, round faces and appear very cute to most observers. Their eyes are large and expressive, as are their ears. Yet the soft exterior of this little tribbethere hides a set of deadly weapons. The jaws of the dune foxhopper are extensible, like those of early repandors, and very long canine teeth near the front of the upper jaw are mobile within their sockets, extending to their full, large size when the jaw is fully opened. This predator has a strong bite force for its size, and any skittishness demonstrated around other animals is lost when it is hunting. Dune foxhoppers can easily kill animals much smaller than themselves, like insects and seednatchers, but can also successfully bring down victims their own size or even slightly bigger, especially molodonts but also ground-dwelling birds, and even other foxhoppers, thanks to their surprisingly large, strong jaws. Demonstrating a wide range of behavioral adaptability, dune foxhoppers can hunt singly, in pairs, or as a pack - in the latter instance, they have the capability to hunt animals at least three times the size of a single individual by savagely biting at the face, rump, and underside in the manner of wild dogs. Confidence is increased in a group, and such packs hunt with the ferocity of far larger hunters. There are few resident large predators in the raindesert, which allows smaller carnivores to fill their roles opportunistically, while still being able to subsist on small prey when there is no larger option available.
The plumed ploveraptor is a medium-sized skungaru skuorc native to polar Serinarcta, with a range around the polar basin. It is fundamentally adapted to feed on beaches, but has also colonized the raindesert adjacent, as that biome has many characteristics with shoreline habitats. Classified as a more basal species within the genus shared with the ticklemonster, plumed ploveraptors differ from that species in having all three toes on their feet, but one less digit on their hands, a generally longer build, and sturdier elongated fingers with partially fused joints, making them more stable but less flexible. These animals use these digits like forceps to feel for prey in loose sandy terrain, as many other birds use elongated beaks. They often walk rather than leap, taking small steps, poking their fingers into the ground together, lifting them and repeating dozens of times a minute. When some small bug or rarely a small vertebrate is detected, the ploveraptor snatches it up between its two digits and lifts it to the mouth to be consumed. Coastal ploveraptors usually forage at the seashore, poking into wet sand for hidden sea life. In the raindesert, these animals target insects and small animals that hide just beneath the sand during the day and emerge to feed after dark - as such, the plumed ploveraptor is primarily diurnal, though it may find the most hunting success right at dawn and dusk, as its prey starts to stir and be more quickly located by sound as it scuttles under the sand. In this biome they favor hunting in the low-lying areas between dunes, which may fill with shallow water and form small, isolated ponds where small creatures gather. Finding food is usually incidental for this species, which is adapted to walk around slowly and probe the dirt until it happens to bump into something, rather than seek out specific targets. Though this may take a long time, it is not very energy intensive, and a few meals will suffice to nourish it another day.
This species of skungaru is solitary, and females raise one to two chicks on their own. Their young are precocial from birth and at once stick with their mother and begin searching for food in the very same way as she does, with no learning process required. If predators threaten, very young chicks demonstrate an amusing defense mechanism in which they quickly lie flat, and if possible, bury themselves in the sand until only their nostrils are exposed; this is useful for their first few weeks when they are ungainly runners. Mothers will endanger themselves to draw predators away from hidden chicks, feigning leg injury and producing loud distressed calls to lead an enemy in the opposite direction. When it has moved far enough way, she suddenly and miraculously recovers, and darts away back to her family.
Named for the sound of its high-pitched and oft-repeated call, rather than for any resemblance to an aquatic Australian cryptid, the funny little bunyip is an intriguing Serinarctan murd related to the caprichel of the sky islands further south.
Bunyips are adapted to live only in the raindesert, where they are common, fast-breeding herbivores that seem to have found a rare niche here where molodonts are slightly less competitive; running over loose sands at high speeds to escape predators. They do this on their hind legs, and because they have two of them, they are more stable and less prone to trip up. The difference is slight, but may make or break an animal's escape from the sudden approach of a flying predator on such unsteady terrain. The bunyip is one of the most numerous animals of any one species which can be found here, and can often be seen dashing wildly from one patch of dune vegetation to another at dusk and dawn. The scales on its toes are long and flat, increasing the surface area of the foot to better spread its weight on the sand, and its hind legs are a third longer longer than its forelegs, reflecting its preferred bipedal locomotion. Feeding mainly on grasses, it eats all parts of the plant from seed to shoot and root, and caches extra food underground for later.
This murd is social, and lives in large warrens, in which they hide from danger, nest, and care for their young, bringing them food until they are almost fully grown. Though it feeds often on higher sand dunes, the bunyip cannot make its burrows there, as the terrain doesn't hold its shape when dug, and so colony members may travel up to a quarter mile from their dens, positioned in low-lying dune valleys, to their feeding sites. The site of a bunyip warren is very easy to spot, for though the entrances are often covered by sand during the day to hide the resident's presence, such sites are likely to be stripped of the usual vegetation which grows in these damper low-lying patches by the murds, which like to nibble on fresh green shoots, but more so like to line their nests with them. Indeed, the bigger a warren grows, the further its members must venture away from it to find food, and this is ultimately how colonies split up into new groups, if eventually the distance to find forage becomes so great that it becomes easier for animals to make a new den closer to the food. As that vegetation is eventually grazed down, groups move on again, and near the original warrens, now less populated, plant life regrows and the colonies grow again, in a repeating cycle. Occasionally the bunyip experiences population booms to such an extent that all of the dune valleys are overgrazed, causing ecological instability that extends far beyond themselves. Populations of this fast-breeding animal crash when food becomes scarce, and this directly affects their predators, too, with several carnivores which depend on the bunyip as a food source like the dune foxhopper experiencing coinciding boom and bust cycles with their prey. When there are few bunyips, dune valleys grow rich and green, and so remaining bunyips start to breed more, and the cycle starts anew.
Bunyips have prominent, almost feather-like head crests comprised of elongated scales very much like those on their toes, which can be raised or lowered to reflect their emotional states. These are present in both sexes, and are not a sexual signal, but rather facilitate communication between all individuals in complex social groups. Bunyip warrens always have multiple entrances sited in different directions, from which sentries peer out to check for danger before anyone can leave to forage. These look-outs must all affirm the all-clear to each other with their characteristic call - "bun-yiiiip-yiiip", which carries for some distance even when individuals cannot see each other, and means it is safe to venture out. Their crests will also be raised suddenly if a bunyip is caught by a predator; accompanied by a different, harsher sound that can be described only as a loud, wailing scream, this can be just enough to startle an enemy long enough to make a break for it and escape. If not, this last ditch cry serves as a warning to other bunyips that danger is near, and to dash for cover before it gets them, too. Other novel defenses employed include balling up and rolling down steep slopes to lose the trail of a predator, similar to the habit related caprichels in the sky islands use, of throwing themselves off cliffs and rolling away to avoid a persistent attacker.
The snitch is a descendant species of gashhopper adapted to life in the dunes around the polar basin. Weighing only eight ounces, this animal is small and delicately-built, with spindly legs, and long digits to support itself while scuttling over loose, drifting sand. The tail is very long, and now lacks ossified bones, or defined joints; several soft, cartilage rods have replaced the structure of this digit in what was once the animal's hind leg, producing a highly flexible whip-like tail used for balance.
Snitches are fierce predators for their size, that spend much of their time resting in narrow hiding places, such as beneath scattered driftwood and rocks, or in tangles of roots below clumps of dune vegetation. Like all siphonteeth, their hind legs face backwards, and they are good leapers, letting them bound quickly between patches of cover when they do emerge to hunt just before sundown, and giving them an edge in pouncing on their targets from a distance of up to six feet away in a single lightning-fast bound. The snitch's diet includes insects, molodonts, and skuzzards, but its favorite prey of all are small, very fat lumpuses which bury themselves in the desert sand during the polar summer, but which come out to hunt throughout the dark polar winter. These animals are very abundant in the dunes, and yet are all but invisible once the sun rises, retreating deep into the dunes to enter torpor, where they are safe from most predators.
Snitches are not good burrowers, and so when the lumpuses retire below ground, they are safe from this hunter, which must switch to whatever other small prey it can run down in the summer, when the constant sunlight renders the sands so hot that it may alternately stand on just two limbs at a time, lifting the others in order to cool them and prevent burns. But the snitch knows when they will have to leave their shelters, and every autumn, as the sun falls low to the horizon, and the winds change toward their winter alignment, the snitches gather in numbers, and wait for a seasonal feast. Male lumpuses awake first, for this is their mating season, and any which wait too long will lose the chance to be the first to meet a partner. But the snitches, too, are waiting for them, and so there are two selective pressures acting on the male lumpuses, one which pushes them to leave early, and another to leave late. The very first to awake are those most likely to slayed by their waiting predators, but after the first wave, there is a period of safety - snitches do not cache food, for they lack permanent burrows, and the shifting sands would simply render hidden morsels buried out of reach. So once the local snitches are all satiated by the most impatient lumpuses among them, the remaining males which might have bided their time just enough to avoid the onslaught, have a chance to leave the sand and disperse across the dunes. The females, perhaps always wiser, or simply without any pressure to get an early start, always emerge after the first round of males, and so they, too, avoid the worst predation by the snitches. But they must get up and go quickly, breaking into mating pairs, and then scattering every one for itself, because if they don't split up before the snitches are hungry again, they will remain easy targets. Just a few days after the autumn sunset, the prey is no longer concentrated, nor easy to find, and the snitches too have broken up widely over the desert, returned to their solitary lives.
The snitch, like most siphontooths that eat food besides blood, is venomous. It has to be, for it can only ingest liquid food, its teeth permanently locked into a syringe-like structure and unable to open its jaw outside a single hollow tube formed by its lower tooth. Its venom, which breaks down cell tissues into a slurry, both kills and pre-digests the animals its bites, so that it can suck out the resulting semi-dissolved fluids that were once organs and muscle tissue. The siphontooth's bite causes tissue necrosis in a larger animal, too, and can result in infections and even the loss of a limb, providing a good defense. Yet because the snitch is so small, producing its venom is energetically costly; to waste it on a defensive bite is a last resort. This species thus announces the danger it can pose to a would-be predator before it bites, hopefully driving it off without it needing to waste its venom, by producing a shrill rattling shriek, often accompanied by a handstand in which the tail strikes outward like the head of a serpent - a sight unsettling enough to discourage some threats even without the risk of a deadly bite.
The clodlopper is a small descendant of the cyclops, a molodont of the poppit clade, that is endemic to the dunes. Sea-adjacent dune systems like this biome are the hottest regions of the hothouse world, and so many species which live here avoid the midday hours underground, and the clodlopper is not an exception. It is only a small fraction of its precursor's size, weighing some 35 pounds - little enough to take shelter from the daytime heat. It begins digging its shelter in a depression between dunes, in a dog-like manner with its front paws. Once it has moved away the loose sand and reached a depth of several feet, it begins to reach the permanently damp sand layer on which the shifting dunes lie. Now it changes the direction of its burrowing from down to horizontal. Its lower tooth still sports two small, forward-curved cusps, and now it crawls on its belly, striking the compacted sand ahead with its teeth in a left to right motion, to loosen it before pushing it out behind it with its paws. In this way, it can create a substantial burrow extending up to 50 feet beneath the dune, where temperatures stay cool at all times.
The clodlopper spends the daylight hours in this secluded shelter, emerging at night to forage. Their diet is broad and omnivorous, but primarily composed of dune grasses - the starchy roots and tubers more than the coarse foliage. The clodlopper gets it name from its feeding behavior; like a garden fork, its tooth cusps are dug under a clod of sand around a grass tussock, and then used to pry it up and out of the ground with a powerful upward motion of the head and neck, cutting the clump of plant matter away from its deep taproot. The animal then consumes the entire plant in big, grinding mouthfuls - after shaking off most of the sand from its roots, of course. The taproot, left deep in the ground, often regenerates new foliage in a number of months after being grazed and so continues to provide stability to the sand dune. Clodloppers will also eagerly gobble up any and all small animals that may also make their dens beneath the dune grasses, including molodonts and lumpuses, and may also put their large, heat-radiating ears to the sand to listen for the quiet scratching of small creatures moving in burrows underground, then dig them out as prey.
Generally solitary, the male clodlopper is aggressive to its fellows, while the female is avoidant; several female territories are contained entirely within a single, much larger male territory, which he patrols nightly. If two males meet, they may engage in fierce sparring with their "tusks" and shove each other back and forth, trying to break free of the other's tusks and slash at their neck. Females share their burrows temporarily with their young, born in litters of two or three and quick to grow to independence during the short summer season. Though these animals live in a "desert", their world is no less rainy than the rest of the hothouse, and vegetation grows abundant during the summer, so that many dunes are covered in low coverings of grasses, and indeed these plants help to keep the dunes from shifting and blowing away. The dunes do not entirely give way to grasslands or forests, however, for every winter the plants go dormant and the winds return, burying the grasses and blowing away much of the organic material in the sand. Throughout the dark winter, clodloppers must pick through the sand to find the hidden vegetation. Though they feed on the grasses they uncover, they ultimately may aid their long-term survival by returning them to the surface of the dune so that, come spring's light, the roots they leave behind - now near the surface - can send out new green shoots with greater ease than if they were left deeply buried. In this way, the clodlopper improves the productivity of is dune habitat.
The wellwaiter is a flickbill skewer related to the cavecreeper of Serinarcta's coalseam caves. It spends most of its life deep beneath the sand dunes, rarely seen, and living a quiet life. A round, mole-like specimen that tends to be about as big as a hand, the juvenile wellwaiter, at this life stage also called a trudger, is much less ugly than its close relatives. Older larvae develop short, fuzzy plumage and develop their eyes early in life, unlike cavecreepers, lending them an almost endearing hamster-like appearance. Matching their appearance, they are docile, and are a pleasant house guest to those they live with. The young wellwaiter's habitat is primarily the deep tunnel systems of the clodlopper seen just above, and sometimes of other burrowing molodonts, which shelter it from the desert sun and from many potential predators. In exchange for a safe home, the trudger keeps the burrows spotless and clean; it is a scavenger, feeding on a wide range of detritus. Clodlopper droppings, though, are a significant portion of its diet, for they are never in short supply, and though discarded by the clodlopper itself, still contain digestible plant matter as well as protein in the form of discarded blood cells, which are quite usable for the trudger's growth. But it is not just the droppings themselves that the trudger feeds on.
Day in and day out, trudgers patrol the clodlopper burrows, eating the "choice" bits, such as undigested seeds it may find, but collecting the rest of the debris and gathering it to the lowest portions of the burrow where they collect it. Here, so deep beneath the dunes, the water table is reached and so water often pools in its caches. This water, rich in dissolved nutrients, soon attracts flying insects to lay their eggs and hatch their larvae, and it is soon colonized by fungi and the fine young roots of dune trees many meters above the burrow. All of these things are nutritious to the trudger, which uses a radula-like tongue to graze films of organic matter from the edges of the puddle and to graze the mushrooms and roots which appear there. Not just one but many trudgers generally live together; they use their especially large forearm claws to dig small connecting tunnels between many clodlopper burrows, and they pool their resources into a single pool to maximize the production of other foods from the raw material. This is the wellwaiter's well - an underground pool, with its own productive food chain, even far below the reach of the sun.
Trudgers spend many years in their infantile state, working as cleaners of the burrow. Over time, they develop a hierarchy among themselves primarily based on size, with the oldest individuals dominating the younger and so on down the line. This eventually results in the very biggest, strongest larvae acquiring the most food, and so growing even larger until they begin to experience a change, a strange compulsion to dig away from the rest of the colony, to hole up in a private burrow far away. Eventually, after as many as 20 years beneath the desert dunes, the most dominant trudger hides itself away and enters pupation. A full year can pass in this state, as it encases itself first in a thick mucous layer, then rolls itself in the sand to protect itself with a coat of sand grains that hardens like concrete. If they have chosen a sufficiently secluded place, this casing will hide their scent and protect them from other trudgers, which will cannibalize their dormant kin. Meanwhile, in the absence of the former boss, the next most dominant larvae will experience its own growth spurt, and so take its place in the line. Often several pupate within the same year, just months apart, though each at slightly different size. Most often, these will be several males, which take less time to grow, and a single large female. With luck, they will coordinate their emergence together.
When a wellwaiter wakes from pupation, it has transformed. Stubby digging legs now emerge long and spindly; a short, blunt beak now arcs long and dangerous. Tiny eyes open again, having not grown in proportion to a now larger body. Feathers remain, but no longer than before; it is an entirely flightless bird, and no trace of ancient wing plumage remains. The trudger has become a trekker; a short-lived, carnivorous dispersal life stage. Now the adult wellwaiters more resemble their sinister cavecreeper cousins; they are hunters, and they ambush the clodloppers which have hosted them for generations. Females, up to twice as heavy as the males that follow close behind them, need the most food immediately upon emergence in order to produce a clutch of eggs, and they often kill an adult clodlopper as it enters its burrow by skewering it through its neck. Males, which only need to sustain a short period of activity, may get away with scavenging a female's kill, or may simply kill a few younger, less lucky wellwaiter larvae. After a single meal, after which it is grossly engorged with food, the female wellwaiter returns to its secluded pupation den, somewhere deep down in the burrow, and seals itself away for another few weeks to digest and grow its eggs. The males leave the burrow soon after eating; having timed their emergence with the beginning of the polar winter, they wander above ground in the dark to find an unrelated female with which to mate, and after doing so they will die; their total lifespan as a trekker is around 28 days. The female lives around twice as long, and once she feels her eggs are ready, she too leaves the burrow.
She now ignores remaining clodloppers, for she has taken all she needed for the rest of her life. A single sacrifice will perpetuate another 20 years of her kind, and on a population-wide level, the single casualty is little missed, and less significant to overall survival than the benefits she provided earlier in life keeping the burrow clean and free of disease. She enters the open air above the burrow for the first time in her life, and soon attracts one or more males. Her eggs are fertilized, and now she travels up to 25 miles in search of a new clodlopper burrow as far from her home as possible, ensuring less related partners for her young when they ultimately mate many years from now. She enters the burrow when its owners are absent and descends to its lowest depths. Usually, but not always, a colony of trudgers will already be in residence. To benefit only her own genetic line, the mother wellwaiter will swiftly kill all of the unrelated larva she finds there, leaving them uneaten, pushing them into the water. Then, and only then, will she lay her eggs in their well. The bodies of the former colony will now ultimately feed her own larvae, which are initially hairless, blind, and able to respire through their skin; unlike older trudgers, they will feed primarily underwater until they grow a little larger and fully develop lungs. A few of the former colony will no doubt have avoided the mother, hidden in small burrows too narrow for her to reach. They will thus, most likely, manage to mature in a few years. But many will have died, and this will open up a number of rungs in the hierarchy for her own young to fill; thanks to her removing the larger competitors, they may have been saved from years of waiting to get in line to pupate. A high degree of intraspecific predation, as adult females cull unrelated colonies and, conversely, larvae occasionally consume pupating individuals, means that this unusual species never becomes too abundant that they begin to negatively affect the numbers of their clodlopper hosts, which would result in their loss of both habitat and the food adults need to reproduce. One of the weirdest of all the flickbills remains balanced with its environment, and the female, having filled her only duty, will soon weaken and die. Her own body joins the well, ultimately helping feed her offspring in their earliest weeks: a rich source of calories that will help them to grow as big as possible in the shortest possible time. Once the carcasses are decomposed, what food resources the well will still grow are less nourishing and growth then slows; it is thus a race to get her young as big as possible before then, to give them the very best chance at reaching maturity themselves.
The ifrit is a small seraph endemic to the raindesert, unique for its lifelong juvenile-like proportions and highly varied diet. While all pteese begin life significantly longer-winged and less terrestrial than their elders, so that they can feed on insects and avoid competing directly with their parents, eventually most of them change into larger, grazing birds, a transformation that mirrors a swallow becoming a goose. The ifrit is one of very few which exhibits a stalled development. Adult ifrits more closely resemble the chicks of other seraphs than the adults, and are strong, agile, fliers that spend much less time walking overland. This difference in form goes hand in hand with their diet; ifrits are more carnivorous than most pteese, eating around 75% animal matter. Much of this is in the form of flying insects, and the ifrit often makes short forays to the shores of the polar basin to glean flying bugs as they emerge from the water, with different prey emerging in spring and autumn. But the ifrit's key to survival is its versatile diet. Its small size is a benefit in the raindesert, a place of relatively few food resources compared to outlying areas, where water is quick to drain away and winds constantly blow sand dunes around, covering vegetation.
Being both small and highly mobile throughout life, the ifrit can locate isolated food resources and quickly take advantage of small things larger pteese would not be able to sustain themselves on. Ifrit diets vary by season rather than life stage. Newly fledged chicks and grown adults all feed on the same range of food. Flying insects are preferred, but the ifrit will catch terrestrial arthropods too, and even swooping upon small vertebrates like skuzzards. Its beak is narrow and finely serrated, suited better to catch animals than in any other ptoose, but it is not a strict carnivore and will also feed selectively on dune vegetation, favoring succulent herbs and roots more than the foliage of grasses. It always travels only in small flocks, but these flocks can cover many miles a day in search of isolated pockets of food. A short digestive system, typical of even of herbivorous archangel birds, lets them digest almost any sort of food, though plant matter is less nourishing than alternatives as digestion is so quick that much of the nutrition remains unabsorbed before it is passed through - this is worse in the ifrit than in larger species, as its digestion occurs even more quickly. To help maximize its nutrient intake, the ifrit partakes in coprophagy (reingestion of its droppings) during periods where it is feeding primarily on plant matter, an unsavory-seeming habit that is not entirely uncommon among herbivores (being particularly typical of the digestive process of earthly rabbits.) Taking nourishment anywhere it might be found, this habit is extended to the droppings of other animals, especially larger herbivores, which are also likely to contain undigested seeds and perhaps a variety of insects.
Ifrits occasionally make use of larger animals more directly, too, by feeding on carrion. A rare abundance of food in the desert, a dead animal will not remain in place for long anywhere, but here fewer large scavengers are present to immediately take advantage of a carcass, giving the ifrits time to often be the very first birds to come across it as they scour the land in search of nutrition. They must be quick, dropping onto the carcass and feeding before anything bigger arrives to displace them. They are not ideally suited to open a carcass, but their beaks are sharp enough that they can often begin opening up orifices to get at the flesh, often focusing first on the eyes and nostrils. Their heads are mostly featherless, which helps keep offal off their feathers, though this trait actually originated to reduce overheating when flying low over scorching desert sands during the polar summer. If anything else arrives, they will not immediately concede; they will stand together, undulating their many wings to reveal bold black and red patterned undersides to their wings and emitting a collective hiss that resembles the screech of a tea kettle - a rather demonic sight. But they are all bluff, and little bite; the moment a larger scavenger shows any real threat, they take off into the sky and flutter away to easier pickings.
Ifrits are generally restricted to the raindesert region due to more effective competitors in the form of other pteese's young, which dwell in more productive biomes outside the range. There, insect foods are more abundant, and the chicks much more numerous and better adapted to feed exclusively on such food; they often exclude this species from feeding enough to sustain itself. For it is a jack of all trades, a master of none; it survives in the desert where dietary specialists might fail, but is less effective at taking advantage of any one of its dietary options against species which are less diverse in their preferences - mostly, the differentiated life stages of other pteese, but also of other much larger types of birds, especially when it comes to scavenging. The ifrit is an example of a specialized generalist: a species seemingly highly adaptable, but actually only suited to survive in a narrow set of environmental conditions.
The dunedevil is a species of strikeworm endemic to this raindesert. A more basal relative of the cliff strikeworm, the sanddevil has a harsher life and a more precarious niche. The long-lived females of this strikeworm species do not have the advantage of reliable permanent burrows as their sky island relatives do - the surface sands shift too frequently, and they are too small to dig out a deep burrow into the stable, damp sand far beneath the dunes. They’ve had to become a more mobile creature in order to survive here.
Growing to four feet in length, an adult female dunedevil immediately calls to mind tropes of the giant sandworm of myth, but it does not actually swim beneath the sand - it is too large to do so efficiently as an adult (however, young individuals are able to "swim" through the sand in this way - albeit, only until they reach around twelve inches in length.) Rather than swimming or burrowing under the sands when grown, the adult moves over the surface, sidewinder-like, and preferentially under cover of darkness; its activity patterns are strongly seasonal, peaking in the polar winter and becoming virtually absent and hidden deep below the desert when the polar summer makes the dune surface too hot to traverse. They hunt by ambush, concealed under a thin layer of sand they sift over themselves, waiting until prey passes by to strike. Eight heat-sensitive pits, resembling tiny, red eyes, detect the approach of warm-blooded targets (and as it relies on this sense, this is another reason it avoids hunting in the heat of the summer.) Prey is captured with a sudden, dramatic lunge and the closing of the false jaws, once its ancestors wings, on its target. Like a living bear trap, it can subdue prey several times its own size, delivering a venomous bite that knocks out its target in a matter of minutes; the hunter holds on throughout the struggle, tendons in its 'jaws' locking closed, for if it let go it would likely be unable to find where its prey ran off to before something else came along to steal its kill. It feeds with its actual beak, small and located between the larger snapping mouthparts, tearing small chunks of flesh from the carcass with death rolls like an alligator. The hunter buries itself several feet underground once fed in order to digest its prey, a process that can take up to three weeks, depending on how much it consumed.
The dunedevil is vulnerable when digesting, as it becomes lethargic and cannot easily flee from attackers that might find it and dig it out. Even much smaller carnivore species of the raindesert are able to target a recently-fed dunedevil, pull them out of their hiding places, and devour them as a pack. This necessitates the sanddevil be able to stand its ground and to defend itself, ideally at a distance before its enemies get a hold of it. Though functionally blind, they can pinpoint where enemies are by their heat signatures, and they will flick sand at attackers eyes to disorient them before striking rapidly; such bites rarely use venom, as the animal is not using its actual mouthparts, only its false-jaws. In true emergencies, they will regurgitate their most recent food as a projectile, decomposed flesh in its soup of stomach acid. It forms a dreadful, highly odorous grease that fouls fur and feathers, and reduces many animals to retching in disgust. To reduce their odds of being disturbed when feeding, dunedevils may choose to hide near aggressive desert flora, including beneath the stiff foliage of highly toxic elkhorn flameflowers and even in the carnivorous tangle of pitpoacher leaves, avoiding being snagged by crawling beneath the leaves, which can only fold upward to catch prey, not down. Thus they can hide safely in a place that spells death to most other animals - and even scavenge on their kills, to the point that the dunedevil could at times be considered a pest of the plant, taking its resources but giving nothing in return.
As in all strikeworms, males resemble their mates hardly at all. Small flying birds with lifespans measured in weeks, they appear infrequently, and most do little except mate. Those of dunedevils are are brightly-colored and highly poisonous, appearing as a rare flash of butterfly-like beauty above the sand dunes. They fly along, not very agiley, with arced wings that share the same bones that the female has modified into additional jaws. They only appear in the first weeks of spring, when the earliest blooming desert flameflowers produce buds that they probe for nectar, and just before the females dig deep into the sand to estivate during the hot summer months. The male collects not only nectar but also terpenoids from its flameflower diet; it lightly wounds foliage and collects the sap onto its wing plumage as a noxious defense against predators, but also for a surprising later use. Mating between such disparate partners is an interesting affair, and does not involve direct copulation. The female raises her tail above her sandy hiding place and releases pheromones to lure him in, then allows him to crawl beneath her and deposit a small (but huge, relative to his size) packet of sperm, which she then picks up in her cloaca, as occurs in some earth salamanders. Each male can mate just once; it has no further energy to find another partner, nor anything left to give, and soon after it dies, right near to its mate.
The sperm packet lent by the male comes with an additional gift: poison. As he leaves it, the male brushes the chemical from his wing plumage onto his "deposit" and when it is taken up by the female and meets her eggs, it forms a defensive cuticle around them, rendering the eggs unpalatable to predators. Later, when she lays her eggs in the damp sand around a dune pool, under the protection and food supply provided by a pitpoacher plant, she can be assured no animal will come along to eat her young before they even hatch. This association in both sexes with dangerous local flora mean that young sanddevils have relatively low mortality and a high rate of survival relative to other r-strategist verminfans, as they are protected bytoxins in their eggs, and typically born in little oases lethal to many would-be predators, from which the females only start to venture away once well-grown, and even then many may stick around these plants throughout life. Furthermore, adult males - poor fliers, and otherwise likely to be easy prey - defend themselves with poisonous defenses that render them immune to most enemies. Though there is no direct parental care in this species, there is very little cannibalism either; the predictable food supply that tends to be found near the pitpoacher means adult females which remain near their birthplaces can afford to be tolerant of young, and multiple individuals in such a place may feed on a single large carcass together. Further away from these oasis, they tend to be more solitary. As a rule, only the larger adult females, in excess of ten years old, may disperse entirely away from dune pools and live permanently in drier habitats, then only returning to wet areas to lay their eggs.
Both sexes begin their lives looking identical, as small, carnivorous or scavenging "worms" living in damp sand near water. Males pupate within a year of their hatching while females are entirely neotenic and never progress past their infantile state, only growing bigger and more fierce, and potentially living for upwards of 50 years.
The lake seademon is a visitor the dunes; though it does not live here permanently, it finds the desert a safe place to breed and rest. This is the most basal member of the Daemonopteryx genus, and diverged before the common ancestor of all others in this clade. It resembles both the other seademons and the far smaller pterdevils from which they evolved, and can be considered a link between the two lineages. At 3.5 feet high at the head, it sits roughly in the middle of their respective size ranges. Yet despite these similarities, this is one of the most behaviorally divergent of any of the tribbfisher group.
This seademon is the only species in the genus to not be found in oceanic environments at any time of the year, excluding occasional vagrants just passing through on migration. It is exclusively native to large freshwater habitats in northern Serinarcta, for it has lost much of the function of its nasal salt glands to filter seawater, and so even when blown off course toward the coast, they may feed in the ocean, but are forced to return inland to find fresh drinking water. Strong fliers, these tribbfishers can be found widely over the northern hemisphere. Large lakes are favored for breeding, and most of the population nests in the dunes of the Hyperborean Raindesert in colonies of several hundred thousand. When it comes to feeding, the lake seademon is very adaptable and can find its fish prey not only by flying low over deep open water and descending to catch shoals of fish, but also by wading and targeting solitary prey. This behavioral plasticity allows it to survive even far from bigger waterways, by hunting in shallow streams and even flooded fields hundreds of miles from any large lakes. It is one of only two seademons - the other being the boggart - to also hunt regularly on dry land, sometimes taking small molodonts in dry upland grasslands.
Unlike other seademons, this animal has little dimorphism between the sexes, and this is reflected in its social behavior. While most of its relatives have far larger, decorated males and subdued females, the lake seademon is colorful in both sexes and females are only 10% smaller than males. While other species are polygamous, lake seademons form lasting pair bonds and together rear their young. This shift in parenting strategy may relate to their inland nesting site, which is more accessible to terrestrial predators than the offshore islands used by others. A single protective male can defend many offspring from occasional flying predators elsewhere as the females go out to sea to hunt, but in the raindesert it has become much more advantageous for many males as well as females to nest closely together, and for those males to not fight one another, so as to collectively defend their nests from enemies.
Lake seademons have evolved a similar coloring to their fur to the feathers of the larger seinebill, a filter-feeding aukvulture which shares many of its varied freshwater habitats, and they are often seen together, despite differing foraging habits. This species, traveling in pairs or small family units outside the nesting season, may follow seinebills on migration and roost among flocks of them for protection from larger aerial predators. The convergent coloring, especially the contrasting deep blue and gold on their heads and necks, may serve to let the smaller tribbats blend into groups of the larger birds and disguise them from predators which might hunt them, but would avoid taking on prey as big as the latter.
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In addition to myriad unique animal species, the raindesert is home to several remarkable plants. In addition to many flameflowers - so toxic that only a handful of small firefinches can even touch them without injury - this is the only habitat in the world for one of Serina's other most bizarre and most deadly flora.
The spinning stranglesnare is the closest relative of the cave chandelier, a sister species which has adapted to grow outside the cave environments in the expansive sand dunes west of the Polar Basin. Like other terrestrial stranglesnares, they evolved from cave species which were washed out of their underground refuge in groundwater, usually as seeds. This species has a more specific growth habit than most others, and always produces new tendrils in symmetrical groups of four. Adult specimens have atypically variable shapes and positions of the spines on their leaves, however, with no predictable pattern. It has the most extreme change of its appearance throughout the course of its growth of any member of its genus.
This species of centipedeweed's transformation is so great, that as it grows up that it goes by two more common names, which are used to refer to very different-looking organisms it presents itself as at different ages. The dune chandelier - the species' juvenile life stage, is a small, rounded plant ranging from as big as a tennisball to a little smaller than a basketball, which travels by blowing in the wind. Its leaves, usually 16 of them, are thigmotactic, so that the tips of each one wraps around the tip of the opposite leaf during early development; each tendril then expands outward along its length into a broad, flat surface. These are airfoils, and they are adapted to catch wind, which causes the plant to roll around the dunes once it breaks free of the connection it has to its parent. Once independent, the dune chandelier's leaves form 16 such airfoils, linked in pairs around the central growth node of its body, and forming a stiff, rounded cage which rolls around like a ball in any direction the wind takes it. Dune chandeliers are commonly seen across the raindesert, generally traveling more east during winter, when the prevailing winds are strong off the polar basin, and moving north-westerly during the summer as the pole experiences more sunlight than the equators and becomes slightly warmer as a result, producing a low-pressure system that draws in air from the south. During very windy periods, these plants can be disturbed from places they have collected in nooks and crannies in the desert, and be released in the wind in large numbers.
A dune chandelier can survive for several years without maturing, even growing though only very slowly, for though it does not photosynthesize, it can digest organic material anywhere that it is deposited - often in piles of leaf litter below clumps of dune vegetation. It is particular about where it settles, though, and will constantly re-orientate its leaves so as to expose the airfoils to wind, so that it continues to move about throughout the year. If it becomes stuck in an undesirable place, like inside a bush or under a rock, it will compress itself down into a disc-like shape, then re-extend itself, moving a few inches in the process, and repeating this over days and weeks until it is free again and can continue on its way. It is unpalatable to grazers thanks to millions of silica crystals which it incorporates into its tissues, which render its leaves semi-transparent; to bite into a dune chandelier is like biting into a cardboard box full of broken glass, and so very few animals would try. But though the dune chandelier, as an individual, can live a transient life blowing in the wind from one side of the basin and back again throughout the year, it can never truly mature and reproduce until it finds the perfect place to settle. And that place is a dune valley - a low-lying spot between large dunes, where water settles permanently, and abundant green vegetation grows.
If a dune chandelier finds itself within such a valley, where no other has already taken root, it undergoes a rapid transformation. Its airfoils fold down, and through back and forth jerking movements over several days, they dig down into the sand like shovels, burying themselves so that only the growing node of the plant is exposed in the sand at the edge of the pool. Roots erupt from the plant's base, securing it further and improving its capacity to pull up water and minerals from the ground. Then new tendrils begin to unfurl from the node, very different from its earlier ones and lined with the razor-sharp spines typical of its genus. The chandelier has become the pitpoacher.
Pitpoachers are carnivores, ambushing small animals which pass over them while coming to drink, mate, or live in the small dune pool they claim. They live for up to five years in this life stage, gradually growing to a size of up to 20 feet across in exceptional cases, though they can reproduce at a size of only 6 feet wide, and smaller individuals (as pictured above) are much more common. Over time, they become mostly hidden by the growth of grasses or other plants, and the water level in the pool periodically may rise to cover the tips of their tendrils, setting their trap. Like those of all stranglesnares, their lash-like leaves will tighten closed around anything which brushes against them, be it the body of a small animal or the leg of a big one, and the more its prey struggles, the more aggressively it wraps around it. Carcasses are pulled into the center of the plant and held there tightly in a fortress of its own leaves to discourage other scavengers; they are digested with enzymes produced from the plant's crown, and the energy gained through feeding this way is stored in an increasingly large tuber below the ground. Eventually, enough energy will have been produced that the now very large, mature plant can shift its priorities from growth to reproduction. It flowers - much more numerously than other centipedeweeds, albeit with no more attractive, tiny, brown flowers. It is unique for the way its seedlings germinate whilst still connected to the parent for an entire year, which allows the young seedlings time to grow the specialized leaves which will ultimately serve them when they break free as dune chandeliers. A single pitpoacher may produce over 60 new dune chandeliers, and as its offspring grow, it can no longer feed, for it curls its tendrils around itself to protect them from grazers before their defenses develop. It will reproduce only once; by the time its young are ready to go off on their own, it will have begun to die. As a final gesture to aid its youngs dispersal, its tendrils straighten out and rise upwards, and there dry up into stiff woody poles, lifting the young up just high enough out of the pit that they can catch the wind and break free to begin their nomadic lives in the raindesert. The death of each pitpoacher after it reproduces frees up a pool for another to take its place, and this is important, for a dune chandelier cannot mature in the presence of another already established in a dunal pool due to aggressive, growth-inhibiting hormones which it produces into the soil, stunting the development of any competitors, even its own young. By dying at this time, a new individual can take root in its place, and the future of the species survival is assured. Reproducing only through sexual means in this way, the spinning stranglesnare is distinct from almost all of its close relatives which primarily disperse through asexual budding.