Centralian Sea

In the middle of the northern continent of Serinarcta,290 million years PE, lies the deepest body of freshwater on the moon of Serina. The Centralian Sea has a significantly smaller diameter than the polar basin, yet holds more than three times as much water, much of which is concealed  underground. At a maximum of 6,250 feet in depth, this inland sea lies in a continental rift formed during the end of the ice age 20 million year ago, when tectonic activity violently returned to the surface for a brief period, splitting the crust in the center of Serinarcta and leaving behind an immense crater which immediately filled with water from the surrounding saturated landscape. This inland sea has many connections into a labyrinth of underwater caves, the coalseams, which open into the sea's rocky coastlines, and some of these are flowing underground rivers hundreds of miles long. Connected to this open body of water and to an abundance of nutrients, the caves that can be accessed from within the Centralian Sea are the most productive cave ecosystems of the entire coalseam system.

The Centralian Sea is located in an immense rift valley, its surface hundreds of feet below sea level. The water of the sea, so extremely deep and with much of it underground, is cooler than the surrounding land. This means warm air is drawn from the surrounding forest and savannah and descends down into the valley, producing strong gusts of wind nearly all the time, which kick up rough waves and make this among the choppiest inland waterways on Serina.This also produces a continuous cover of fog that drifts across the water, obscuring its shores, and making the sea appear even more vast and mysterious than it already is.This fog usually persists even on the sunniest of days. 

The seinebill is a skimming aukvulture native to Serinarcta, where it is mainly endemic to large freshwater lake systems. Though it may occasionally venture into coastal oceans, and even more rarely cross the seaway to reach Serinaustra, it does not usually breed there. With a wingspan of 15 feet, this descendant of the stormshadow is now a relatively small example of a "giant" aukvulture.

Seinebills are quite big for a seabird in the hothouse, as they don't rely on eyesight to find fish, and so are not immediately less competitive than tribbfishers. Their lower beak is longer than their upper and formed of many narrow plates which grow into elongated "teeth", forming a cage-like structure. As the bird flies low over calm water, the bottom mandible trails through just below the surface. The teeth are widely spaced in front, allowing any small fish and invertebrates that happen to be in its path to be scooped up. They narrow toward the back, however, allowing water to flow out, but keeping this prey held in place as the bird pulls its bill forward through the water. When this "cage" is filled with small food items, the bird closes its mandibles, sealing the slots in the lower jaw with shorter, outward teeth on the tip of the upper until the bird tips its head back and swallows its mouthful. 

Because its manner of feeding doesn't require seeing its food, seinebills can hunt both night and day - with the caveat that they are only effective hunters in areas of predictable, high prey concentration. This keeps them mostly out of the ocean, where fish stocks are widely scattered and may be here today but gone tomorrow. In winter, large flocks of these birds migrate north to the polar basin against the movements of most other birds which leave at that time, in order to take advantage of shoals of normally benthic fish which rise to the surface in the darkness - and it is then, in the darkness, that they breed on sandy offshore islets, raising their chicks in darkness with far fewer competitors and nest predators than in the daylight months. In summer, as the basin is choked with floating vegetation, the seinebills depart, many of them spending the rest of the year along the Centralian sea and surrounding waterways that are sufficiently rich in food and calm enough to skim the surface. Though nesting itself occurs in the polar winter, the male seinebill is far more colorful than seems necessary to attract a mate in the dark, adorned with bright steel blue and yellow feathers on its head and chest. This is because courtship occurs during the summer, before pairs migrate north. Young, single males impress potential partners, who are mostly white with tawny heads, by raising their feather crests and flashing their bright plumage with great exuberance, accompanied by long, drawn out trumpeting calls. Once paired, however, they are monogamous, and so in ensuing seasons the courtship dance is condensed to a short bond-renewing waltz, where each partner mirrors the movements of the other, just before the couple fly north for the winter. 

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Connected as thy are to underground caves, the depths of the Centralian Sea are inhabited by a variety of endemic fish and invertebrates that have lost all faculties of sight. But in this sea, it isn't only the fully aquatic species which have become so specialized. This is also the habitat of the largest smol in the world, a completely sightless molodont that descends from burrowing animals of the surrounding plains. The ancestor of the massive 2,000 pound molrus was the tiny mole-like mudmuncher, a carnivorous smol of the ice age, which found its way into the depths of these caves while seeking food below ground almost fifteen million years ago. Already a good swimmer in the surface world, once within the cave system they became increasingly aquatic as they pursued worms and crustaceans in the shallow water there. When one population of these cave colonists navigated their way through the dark, flooded caverns and found its way into the open waters of the centrallian sea, they found larger and more abundant prey in the open waters and so grew in size to tackle it, becoming far bigger creatures. Today the molrus, while still completely blind, is too large to find food in the caves any longer and has become a permanent resident of this inland sea, where it feeds primarily under cover of darkness upon benthic molluscs and crustaceans. Pre-adapted to tolerate low oxygen levels as a burrowing species, the molrus can hold its breath as long as two hours as it dives to depths of 4,000 feet, reaching the point where oxygen becomes extremely scarce and few higher organisms can survive.

 It forages by touch, with its long whiskers picking up water vibrations and the presence of prey nearby, and by echolocation, emitting clicks that produce echos absorbed in a fatty pocket on either side of its lower jaw where they are carried through the jaw bones. Food is collected by digging bivalves off of the rocky substrate of the basin with its extraordinary horn-like teeth, which together form a beak to pick them up once loosened so that they can be tipped down into the mouth. The greatly enlarged upper tooth of this animal is unlike most molodonts, and its shape prevents chewing in the conventional manner of these animals in a wheel-like rolling motion. Instead, the molrus simply positions its hard-shelled food between the base of both teeth and pulls the entire upper jaw backwards to crack the shell. It is then swallowed otherwise intact and broken down further in the digestive system through the mechanical grinding of a gizzard-like organ just above the stomach. Like a bird, the molrus swallows stones to aid in grinding food in this structure, and eventually regurgitates them as they wear down too smooth to be of use.

Molrus don't typically feed deep in caves, but still rest as well as give birth in them, especially those with submerged entrances, and here avoid land predators. Adult males, which can surpass a ton and outweigh females by some 600 pounds, may however have to haul out above ground to rest whenever they need to leave the water, as their size can make navigating many caves difficult. While the mudmuncher was largely ectothermic, the molrus has regained a degree of endothermy, raising its body temperature prior to dives into the cool depths of the sea, and taking a long time to cool down again due to its high mass; basking in the sun, when safe haul-out sites above ground can be utilized, helps both sexes to warm up again more quickly. Smaller females may depend on the protection of the formidable, large males when doing so, with the males using their teeth to joust and claim territories for frequently changing harems of females to utilize as they come and go, mating with the male present when receptive; these males will also attack predators that threaten their females. Foraging usually occurs at night, where they are less visible to sighted animals including those which could hunt them, though at significant water depths this is a non-issue as the water is murky and dark regardless. Though this animal is entirely blind, it has evolved eye-spot markings on its head where its eyes would be if it had them, purely to trick other animals into thinking it is watching them, and so discouraging attacks by predators that rely on ambush. Perhaps comically, the molrus has also evolved an even larger pair of these markings on its hindquarters which may trick enemies into thinking it is staring right at them even as it is is actually busy digging up shellfish with its head positioned toward the sea floor. In any case, without real eyes of its own, the molrus itself cannot see any of its patterns; their existence is the result of millions of years of random pigment mutations that happened to improve their survival by eventually taking on the appearance of eyeballs.

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The pengwhales are another group of marine animals that are found only in the Centralian Sea. A small family of just three species of fully aquatic dolfinches, they evolved from the only one among them which could reach this isolated body of water by meandering through shallow wetlands and solid ground: the platyporp. They include the largest birds endemic to the sea.

The most numerous pengwhale, however, is much more modest. Reaching six and a half feet beak to vent, the openbill pengwhale usually weighs 260-330 pounds. Very handsome, its pattern is a bold, contrasted black and white, with sharp countershading, scattered dark speckles on its ventral side, and a pale yellow patch on either side of the neck. The skin is smooth, streamlined and completely featherless, becoming a soft pink shade along the jaws and nostrils. Most unusually, the beak of the openbill, as its name would indicate, is permanently angled open at the back, revealing two comb-like ridges each of over 250 hair-thin, bristly keratin teeth. This species is a filter feeder, taking advantage of a uniquely freshwater food source - insect larvae, which float suspended near the sea's surface in vast swarms. It takes bites at the surface, quickly squeezes the water out the sides of its beak, sieves out the bugs contained within each mouthful, and repeats all day long, over the day collecting millions of the tiny larvae that make up some 80-90% of its diet (the remainder is small fish, which it can still catch in the serrated tip of its beak.) So numerous is this food source that the openbill pengwhale is the most common megafauna of this insular sea, with a population of around 2.5 million animals.

Such numbers don't go unnoticed. Lacers are the openbill's main predators, and it one of their most common prey. Their surface feeding habit leaves them especially vulnerable to its attacks, but they are not without defenses. Their numbers lend some safety, with more eyes to spot threats, but also to coordinate another defensive maneuver: a smoke screen. When a pod of openbills is targeted by a lacer, the entire group will excrete a dark, ink-like secretion from their hind ends. Singly, it does little to deter attack. By the dozen, it blackens the water, temporarily hiding prey from predator and giving the openbills the time to rapidly descend straight down in the water, to a depth that the lacer can or will not follow. Able to hold their breathe for around 12 minutes, the pengwhales then resurface several hundred feet away from the threat.

Openbill pengwhales don't care for their offspring for nearly as long as other dolfinches - it isn't feasible to protect them in the open water that the adults need to feed in, and these pengwhales cannot go very long without feeding, as they don't store much body fat (it is not necessary in shallow surface waters in this tropical climate.)  A litter of two to six young are born in the shallows, in areas of thick vegetation, and stay with their mother for less than ten days. At birth, each is around 20 inches long and weighs perhaps 10 pounds. They can swim immediately, and mostly feed themselves, though the mother provides an initial meal or two of regurgitated insects. The chicks strain the water for food much like the adult. The initial supervision lent by their mother is mainly to deter predators before the young are fully competent on their own. When she leaves them to return to deeper waters, they will have already been fully self-sufficient for several days, and they then scatter into the plant cover near the shore and in the immediate tributaries of the sea. This will provide them shelter for the next year and a half of their life, until they begin to make forays further out to sea when they are less vulnerable. Growth is rapid, and sexual maturity attained in as little as two years, with full size attained around the same time.

The pied pengwhale is the biggest animal living in the Centralian sea. It is a titanic whale-like filter-feeder, capable of reaching weights of up to 40,000 pounds, equivalent to an arctic sea horse. Together, the two are the largest animals which have ever evolved in freshwater, artifacts of the hothouse's especially vast inland waterways.

These huge animals, despite their size, are very closely related to the other pengwhales of the Centralian sea ecosystem, and share their genus with the diminutive openbill pengwhale, with which they also share their filter-feeding teeth. The mouth of the pied pengwhale closes completely, but its keratin teeth are wide-splayed, with those on top extending outside the sides of the mouth. There are over 5,000 of them total, on both its upper and lower jaws; the openbill pengwhale also has teeth in both jaws, but those on top are very small and largely vestigial. Such a vastly differing "tooth" count may seem to suggest the two animals should be less closely related, but the teeth of these animals are simplified, bristle-like keratin structures, which are far more easily produced and multiplied than the true teeth of other vertebrates or even other bumblets. The upper and lower teeth of the pied species interlock into a seining net and are used to filter crustaceans and benthic fish from the sediment at the sea floor. Feeding like a gray whale, this colossal dolfinch swishes its head side to side, taking mouthfuls of sand and expelling out the debris to collect the food hidden within.

Adult pied pengwhales have no predators in the Centralian sea basin, and so they have long lifespans. They are slow-moving, docile, and have lost the natural counter-shading pattern common to almost all marine animals, as they have no need to hide form either predator or prey. They have white topsides, while the lower surface of their flippers is black. Vibrant stripes and belly spots are useful for species recognition and social communication. Because of their large size, pied pengwhales often forage singly, but they are social animals too and occasionally pairs or smaller groups will spend several days together socializing before going their own separate ways. Schools of openbill pengwhales will flock closely alongside them when they rise into the shallows to breath, using them as a living shield against predators such as the lacer. Though tolerant of its cousins, interactions between them are limited and primarily based on self-preservation; as such, when danger passes the smaller pengwhales go on their way, and if the attention proves too much, the larger pied pengwhale will dive out of reach of its pesterers.

Young pied pengwhales live very different lives from their elders. They are, at all times, much more numerous; like a majority of platporps, young are born in litters rather than singly, in this case as many as six at a time. Pied newborns weigh "just" 200 pounds, and are bite-sized to the lacer. Females don't attend their young for longer than a few hours, only assisting them to the surface for their first breath and then abandoning them, for the habitats needed by each life stage are not compatible. Adults live in the deepest depths of the sea, while juveniles are born and spend their lives in shallow, vegetated waters and in particular along the outflows of rivers near the edge of the sea. Predation is hard on the young ones, and most births ultimately produce no survivors that live past a few months of age: less than one in thirty reaches adulthood, if it is very lucky. But the adults which do make it, and exceed the size of their enemies, can live for over 70 years, reproducing every couple of years. They have time to maintain their numbers - their frequency of births, litter size, and high infant mortality all come together to ensure the species does not overpopulate a limited food supply in an isolated, inland sea where dispersal to new territory during food scarcity is simply impossible.

There exists a third pengwhale in the Centralian Sea that is very unlike the others. More distantly related to the other two species, this species is in a monotypic genus and has no close relatives. It is a basal pengwhale that never became larger, and it is a true miniature, weighing only 40-50 lbs, and stretching just two and a half feet in length. Don't let its small stature fool you though, for the pygmy pengwhale is by far the meanest and least abiding of all three species, to the point it is also known, perhaps even more appropriately, as the fangface. It is notable for its very unusual social structure relative to its relatives.

The fangface, unlike its cousins, is extremely territorial. Also unlike them, it is a strictly coastal specialist, never occurring in water more than 60 feet deep. The fangface is not especially fast, but just like the giant pied pengwhale, it doesn't really need to be. It is a specialist predator of small aquatic animals, mostly goby-like benthic fish, crustaceans, and insect larvae, which they catch by rolling over loose rocks. Each animal controls a territory of around one city block, or around 300 by 800 feet, stretching along the shore, in which they collect as many rocks as they can, over time forming huge rock piles, almost like reefs, which attract their prey in much greater population density than would otherwise occur. Algae grows in abundance on the rock piles, but higher plants are plucked and removed for ease of foraging; this results in specialized little algal gardens with unique biodiversity relative to areas of the sea which are not inhabited by the fangface. These little pengwhales don't share their food supply, and both sexes have evolved a pair of hypertrophied fang teeth on their lower jaws which are used in aggressive intraspecific combat. Males have evolved very vibrant colors - purple and gold - which would not show up in deeper waters, but which here let females see them clearly from a distance, so that the male can strut and display without having to enter a female's territory and risk his own safety. The only time one adult fangface is allowed in another's territory is to breed, and a receptive female will approach a male if she wishes to breed; the process is brief and fleeting, and moments later, he drives her away with a few gentle bites to her flippers.

Female fangfaces give birth to litters of two to four young and protect them fiercely for several months, at this time becoming even more aggressive, and often expanding their territorial boundaries by up to 20% to accommodate the needs of several growing youngsters. Juveniles avoid adult aggression with very different patterns than the adult, or a lack thereof - they are solid black, fading to gray on the belly, and are much less aggressively treated than other adults even by unrelated animals. Young do not develop adult coloration for some 18-24 months, allowing them to disperse from their mother's territory and find an unclaimed patch of coast without being immediately targeted by their neighbors. Even so, the coast is a busy place, and open territories are few and far between - though predation occurs on these small animals and so new land is always being made available, if populations are very high for an extended period, many adolescents will be unable to find a territory and may starve to death or be killed by rivals.  Female fangfaces have some capacity to prevent this; if stressed by overly limited territory, such as may happen when too many animals are competing for space, she can delay the development of her embryos by up to eight months, hopefully by which time conditions will have opened up and improved.

The sea kitten is a tiny, aquatic foxtrotter which is found only within the Centralian Sea basin. One of the smallest 'marine' tribbetheres ever to live, the sea kitten is truly diminutive and weighs only three to six pounds. Despite this, they are skilled divers which hunt fish up to 225 feet below the surface and which can hold their breath for around 70 seconds as they paddle with all three of their webbed limbs at a frantic, energetic pace. Sea kittens form their own independent branch from all other Serinarctan foxtrotters, and have no close living relatives, though their earlier ancestors were weasel-like predators which were outcompeted over time by stoatshrike gravediggers in terrestrial ecosystems. 

Nocturnal, very wary, and spending most of their waking hours hunting to sustain a fast metabolism, the sea kitten is difficult to observe. Its pelage is an iridescent violet-black, with white around the muzzle, eyes, and ears, and very oily so as to resist intrusion by water which would cool the animal down. Sea kittens frequently climb out of the water on rocky coasts to groom themselves in between dives, keeping this fur coat in order and free of dirt so it remains insulating. The slightest sound, though, and the animal darts in an instant back below the water and swims as far as 250 feet away before popping back up and checking whether the coast is clear. They hunt within the zone of depth which is illuminated by planet light, and though even on a fully lit night the water is still very dark to human eyes, the huge, soulful eyes of the sea kitten are each as big as its brain, and can collect tiny traces that we could not. Long white whiskers all around the face are also used to detect tiny movements in the water indicative of fish nearby as well as when moving through very narrow gaps between rocks out of water, where the creatures make their dens and sleep during the day. Sea kittens pick hiding places with as narrow an entryway as possible to protect themselves from their many possible predators, and they have some adaptations to squeeze though such small spaces, which are retained from their ancestors that hunted in burrows on land. These include a flat-topped head, front limbs that can splay out to the sides, and ribs hinged at the spine which can flatten to fit into any space the skull can fit through.

Sea kittens are social animals and share dens amicably - the typical group is a mated pair, their immature offspring, and sometimes an adult relative (or several) which assists in child-rearing. A litter of up to eight kits is born at once, each weighing only one to two ounces at birth, and one parent stays with them at all times for two weeks while the other hunts; as they grow, they require both parents and any helpers to all hunt at once to bring back enough food to sustain them. The kits are very noisy as they grow bigger, emitting loud cries very much like earth kittens when hungry, which can sometimes alert predators above to their presence, though few can access them in their dens as they are normally situated securely underneath piles of large boulders. The young are only tended as long as absolutely necessary before their parents begin to demand the kits leave the nest and join them in the water to learn to swim and find their own food; they are typically weaned by four months of age and some may go off on their own at this time if food is abundant. Adult sea kittens retain their distinctive cat-like voices throughout life and communicate with mews as well as sharper, bird-like chirps. They are playful even when grown, and social bonds are often strengthened with bouts of chasing and wrestling as well as lots of grooming of each other's fur.

The stormshadow species has split into many over the last ten million years, and among its descendant forms of 290 MPE is one of the most aberrant of the giant aukvultures, for the adult of this massive winged predator has lost its powers of flight. For while the young of stormorants are born with wings and can cross the skies, they lose this ability early in life, as they become completely adapted to make their lives in a place their ancient skydiver ancestors knew very well: in the water.

There are several species of stormorants, which range rather wildly in size from just six feet high, in certain species that make their homes in shallower river systems, to the emperor stormorant of the vast, deep Centralian sea. This species reaches a height of ten feet and is very robust, the adult having solidified bones and a very muscular body that can bring its weight up to 400 pounds. Stormorants are aukvultures that have evolved, once again, into diving birds, specializing to this lifestyle fully, at the expense of their flight. Mature animals have no flight feathers, and their wing digit is webbed, functioning like a flipper to propel them in "flight" underwater as they seek fish to depths of up to 2,500 feet, and hold their breath for more than 30 minutes at a time. The long arms of the emperor stormorant, a remnant of its flighted ancestry, leave it a slower and less streamlined swimmer than most marine animals of its size. Instead of chasing prey in open water, it more often dives all the way down to the substrate, and there feeds on more benthic prey which it traps against the seabed and snaps up in its especially long and narrow beak.

The stormorant cannot just reduce the length of its forelimbs because the juvenile of the species is still capable of flight, and there are limits to how much the structure of the limb can be adjusted through its growth. Chicks are born at just one pound in weight and more resemble seagulls than the strange giraffe-penguin hybrid that is the adult. They have fully-developed wing feathers, and they depend on their ability to quickly take to the air to avoid predators while their parents leave them on the shore of the sea to feed. Though they can swim on the surface from infancy, they only begin diving around two months of age, and do not lose their power of flight until around four months, when they weigh around thirty pounds, and flight becomes less necessary for their survival as they can take care of themselves and cavort in the shallow coastal waters while their parents forage for food. The flight feathers are not entirely lost until up to a year of age, and the in-between stage is awkward at best, with the adolescents often sporting arms lined with a handful of useless, scrappy feathers that eventually break off and are not replaced.

Though they are at home in the water and find all of their food there, emperor stormorants do not sleep there, and must be able to rest on land, which limits them to a range within a few tens of miles from shore. They haul out almost daily for at least a few hours, gathering in gregarious flocks of a dozen to more than two hundred, depending on season and local prey density. Courtship, breeding, and of course nesting all occur on land upon rocky coastlines, preferentially on islands safer from land-based predators. Like most giant aukvultures, males and females form enduring pair bonds and both work to feed their young. Females brood five to fifteen pupa in a simple nest of stones and seaweed, usually colonially among others, which provides safety in numbers. After a few weeks of care by their mother around the nest, chicks of different parentage gather in creches for protection as both adults start to leave them to hunt together.

As a rule each pair only will tend to their own chick, however, and the young recognize their parents by voice and come running from the group to get fed when they hear their mom or dad returning to the colony with supper. Adoption of orphans at an early age is rare, as adults recognize their own young and can even count them to know they are all accounted for, and will refuse to feed others even if they are mixed with their own chicks, snapping at them and pushing them away. Care of unrelated young chicks may occur when females lose their own young at an early stage in their development, however, especially if the loss occurs while they are still bound to the nest. Such mothers, mourning their own young, may not have had time to come to recognize their own chicks and will show parental instincts toward others that approach them as a result. Any chick, however, will take advantage of such a parent to get a free, extra meal and so improve its own survival odds, even if it has parents, and this means that true orphans, which are likely to be weaker and less able to compete with the healthy "freeloader" chicks, will still very rarely be fortunate enough to be adopted by such a willing parent. Conversely, adoption of older chicks, once they are spending most of their time in the water, is commonplace; perhaps by this age, as the young are already learning to find some of their own food, it is less of a burden on the adult to take in a foundling. It is also possible that they simply lose the ability to recognize their own young as they grow more independent, are interacted with less, and need less supervision.

But the most likely reason is that the risks of helping another chick decrease as they outgrow the size of a pesty nest parasite, an adult bird which has evolved to take advantage of stormorants by imitating the behavior of their youngest chicks to get a free meal. It might not be so bad to feed another of your own species, even if it isn't yours - but the emperor stormorant has evolved to avoid caring for this parasite species, even though other stormorants still will do so. It is a good system for the survival of the species, even if it comes at the expense of real orphaned chicks in need of help.

Unlike the polar basin, the Centralian Inland Sea has no direct ties to the ocean. As such, its animal life has evolved from freshwater lineages, and from terrestrial land animals, with little overlap with oceanic clades. There are no whiskerwhales or whelicans in its waters; instead, animals such as the molrus have evolved - a giant, walrus-like and totally blind molodont evolved from burrowing smols. Here, too, the flying aukvultures returned to the water with the giant, penguin-like stormorant, which is found nowhere else. It is expected then that the large predators of this sea also have similar origins, and this is true as well for the lacer, a giant aquatic gravedigger which is found exclusively within this inland sea.

The lacer, pronounced "lasser", is so named for its lacerating bite. It evolved over ten million years from the cookiecutter kittyhawk, already a capable swimmer. Reaching a weight in excess of one ton, the lacer has become a seal-like animal with a vicious, debilitating bite. Its beak teeth slot into each other as they bite, producing a shearing effect to easily slice large mouthfuls of flesh from prey animals like the pengwhales, and cause rapid death from the trauma. It swims with great agility, almost like a dolfinch, as its front legs have turned into similar paddle-like flippers. While much of its prey dives deep into the water in pursuit of fish, the lacer stays within a hundred feet of the surface, ambushing its prey as they come up to breathe or haul out on dry land. Its attacks are typically high-speed and targeted at the backsides of its victims and involve quickly removing a chunk of flesh and retreating as the prey animal struggles from its wounds and usually drowns. Then the lacer circles back around and feeds quickly, before other scavengers arrive. Occasionally prey such as the molrus, with its huge tooth beak, prove too dangerous to subdue, and most adult lacers bear scars of failed predation attempts on their mostly featherless hides. Young molrus are hunted more successfully than the adults, and the largest males are mostly safe from predation.

Like many gravediggers, lacers lead solitary lives. Males and females mate in the water, then go separate ways. Females raise a single offspring for two years and give birth on land, keeping the chick safe and fed on a rocky ledge for three weeks without ever leaving to feed, and so relying on stored food in her gut to provide to her chick. After this, she hides it on land in dens hidden in the rocks for around eight weeks in total, leaving it to hunt and then returning to feed it, until it is finally strong enough to follow her out to sea and there remain with her in the water. After this age, lacers return to shore irregularly, sometimes spending months at sea where they sleep near the surface in the manner of the dolfinches it hunts, resting one half of their brain at a time.

The Centralian Sea is by a wide margin the deepest body of freshwater on Serina. And in its depths lurk monsters that never see the sun... this inland basin's lowest levels are so deep as to be permanently shrouded in an eternal darkness. Unlike most freshwater bodies, this sea does not have an anoxic layer, as deep underground fissures constantly release fresh, warmer groundwater from surrounding underground caves into the lake, producing rising currents of water which keep the basin circulated. This makes it the nearest thing to the deep sea which has ever existed in freshwater, an ecosystem of dark and decay fueled by highly concentrated nutrients which fall down from the heavily vegetated sunlit waters above, and from organic material carried into the basin from its many drainages. The abyssal zone of the Centralian Sea is vastly richer in nutrients than in any ocean, and so the density of animal life which can survive here is also many times greater.

The abyss lurker is a massive thirty foot long blind sea dragon, a descendant of the spectral cave dragon which by ten million years ago was already fully adapted to life in Serinarcta's vast, flooded underground caverns. The lurker descends from cave dragons which were washed down deep into the furthest depths of the caves and through underground rivers with their outlets thousands of feet below the surface, in the dark depths of the lake basin. Once here, they rapidly increased in size with an exponential increase in available prey. This gigantism comes at the expense of their once astonishing lifespans: always active and feeding, here they can live only around 120 years. Not even their young, born alive and just a tiny fraction of their mother's size, spend any time at the surface in its relative safety of vegetation and hiding spots. They scatter to the waves, eventually settling down in crevices along rocky undersea cliffs, and with luck will not come across their parent again until big enough to avoid being taken as a meal.

Abyss lurkers are silent, slow-moving predators which feed in both open water and along the steep, rocky slopes of the basin, but which do not generally descend to the bottom sediment. Without any trace of eyes, they float nearly motionless for many hours, and rely on long whiskers to sense tiny vibrations in the water. When something comes close by, they lurch forward, snatching sometimes a fish, sometimes a strange visitor from the alien world far above. But it is carrion which they do not wait for. An incredible sense of smell alerts all of the lurkers around whenever something big has died and begun to sink. They rise in the water and gather as a swarm to devour it, ripping flesh from the carcass in huge chunks and quickly making short work of even the grandest creature, before returning to the depths and their mysterious world without sun.

But it isn't the largest carnivore of the sea which is the most threatening - not really. For you are much more likely be be harmed by one which might seem, at first, much less threatening. One of the deadliest predators of this sea is not an animal at all, but a vicious plant. 

Kraken is a colonial species of stranglesnare centipedeweed that is endemic to the Centralian Sea basin. It originates from ancestors living in the cave systems below Serinarcta, and its predesccors washed out of the many outlets of underground rivers into this basin several million years ago. As it evolved from a cave ancestor, kraken is non-photosynethic and lacks symbiotic algae to aid it in acquiring sugars, meaning it is entirely heterotrophic and must eat to live. It is able to digest animal prey and break tissue down into energy thanks to fungal genes acquired into its genome through ancient horizontal gene transfer.

This species of centipedeweed is distinctive for the huge sizes it can acquire; individual plants can grow tendrils up to ten feet in length, though six is typical. But this plant never grows as a single individual. It forms immense, dense thickets of clones - hedges that colonize specific habitats to the exclusion of most other plant life. Their habitat is rocky freshwater coastline, where waves regularly break upon the coast. Intolerant of saltwater, and unable to take root on sandy shoreline, the kraken is therefore limited to this one inland sea. Kraken's growth form is basically to form a living, flesh-eating barbed wire fence, and single colonies can grow to cover dozens of linear miles. Sexual reproduction is very rare, and a few individuals dominate the entire lake basin; though they may split into multiple colonies over time, they remain a single genetically identical individual. These plants rely on wave action to bring food, which they filter from the water with their many layers of spiny leaves. Carrion is the bulk of the diet but any living thing which is washed inland and becomes snared is also on the menu, from fish to seabirds, the eggs of marine life, up to animals as big as the pied pengwhale if they become disoriented and swim inland during storms or other events (kraken's diet is not limited to animals, either - it is an omnivore, and much of its energy also comes from digesting seaweed and algae.) Prey is held tight by dozens if not hundreds of hard, sharp tendrils, each of which tightens and coils whenever it detects it has caught something, and slowly pulls the carcass closer and begins dissolving it; this species is distinct for forming a digestive surface over the entire length of its tendrils rather than only at its crown, and it adheres itself to a meal for as long as it takes to digest it - it may take well over a month for the biggest carcass to break down. Such large kills also attract scavengers, which may also become snared and eaten by this sinister plant. With such an expansive diet, the kraken is the fastest growing centipedeweed, and can grow a new 6 foot long tendril in less than 24 hours in ideal conditions.

Of course, conditions are rarely so ideal. The wider that a kraken grows, the less stable it becomes, and the more likely it is that part will be torn from the rocks its roots adhere to. This is fatal to the plant, for it is denser than water, being made mostly of silica, and so it sinks to the bottom to drown: it can now endure several days below water, but no longer, for it still relies on atmospheric oxygen to breathe and is not fully aquatic. This also means that the kraken is not tolerant of prolonged sea level rise, limiting it to a narrow range of suitable habitat neither too low as to become submerged for too long, nor too high as to be left in the open air, away from its primary source of food. It also means that though kraken can form very long colonies, covering entire coastlines, these colonies are also very narrow, usually just a couple meters in width and sometimes less. Some animals can also hold their own against the kraken; the molrus in particular uses its large beak-like teeth to pull the plants from rocks and toss them out to sea to die, in order to create suitably open basking sites for themselves, and indeed this species is their most limiting factor - a functional predator, even though it does not actually consume the plant. In these ways, even this aggressive, fast-growing killer plant from the underworld is kept in balance with its ecosystem, and under control.