Corsola
Corallium carus
Overview
Corsola jewelry has always been popular in cultures located near reefs. Worldwide it has long held an association with fertility and the protection of children and women. This belief likely stems from the relatively rapid regeneration of the species.
In some times and places corsola has been very, very popular. Maurya India and 19th Century Galar are two such examples. These spikes in demand tend to drive local corsola populations extinct and drive up the price worldwide to the point where corsola jewelry becomes a status symbol everywhere.
Alolan corsla are now facing a new threat: toxapex. The introduced poison-type can crawl over reefs and leave them dead. They can even snag corsola from the water with their tentacles or knock them down to the substrate with their ranged attacks. In light of this threat, the Alolan population has become seriously endangered.
That's how the popular story goes. In truth, there is no evidence that toxapex outbreaks do permanent harm to either the reefs corsola live on or the population of the species itself. Their predation of old coral and corsola might enhance the biodiversity of reefs and the long-term prospects for corsola populations. Reefs and corsola have been declining for decades, but the blame rests on anthropogenic causes: climate change and chemical spills.
Corsola are the rare water-type that can survive out of water for more than an hour. Many trainers mistake this for an ability to live out of seawater most of the time. Corsola still need to rest in saltwater for at least eighteen hours a day. Stasis balls or aquatic habitat balls can be used to delay dehydration long enough to get to the next Pokémon Center. Corsola will not thrive on the trail but they can be used by traveling trainers. They are still best suited for stationary aquarists with a greenhouse pool or a large reef tank.
Physiology
Corsola are classified as a dual water- and rock-type.
The species comes in many colors. The most common color scheme in Alola is a predominately pink body with a white underside. Individuals can also be blue, yellow, maroon, or green.
Corsola's body is mostly made up of a hard, porous armor made of calcium carbonate. The rest of the body is either hollow or filled with the soft, flexible tendrils of the actual pokémon. Surprisingly, corsola are relatives of starfish. A particularly hard shell surrounds the pokémon's core. Each of a corsola's four to six horns contains a small cluster of nerves. In ideal conditions corsola can regenerate their entire body from the core in less than two days. A broken horn can form an entirely new corsola in about three weeks. The durability of their armor and rate of regeneration make corsola difficult to hurt and almost impossible to kill.
The pokémon has functional eyes and surprisingly high intelligence. Their mouth contains hard tooth-like structures that help them break off chunks of coral and grind it into smaller pieces. They prefer to target dead coral but will eat live hard corals if necessary.
Corsola primarily 'eat' via photosynthesis. They are not themselves capable of converting sunlight, but they attract small organisms called zooxanthellae to live within the protection of their armor. These zooxanthellae, in turn, make food for the corsola. Other symbiotic bacteria make the proteins that let corsola bind the layers of calcium carbonate together.
A corsola's body contains various cavities, valves, and simple pumps. These can be used to adjust the pokémon's weight and allow them to rise or fall in the water column. Weak hydrokinesis can propel them to the surface where they can then fill all of their cavities with air. They are at their fastest on the surface, but this is still only fast enough to resist weak ocean currents.
Corsola can live for up to ninety years in the wild. Their maximum captive lifespan under modern care techniques is currently unknown. Corsola can grow to be three feet tall from base to the tip of their horns and weigh up to forty pounds.
Behavior
There are two types of corsola groups: gardens and rafts.
Gardens of corsola live on coral reefs. They usually settle into the existing reef and bind themselves to the coral with hooks on their underside. This gives them additional protection from attack and anchors them during violent storms. Corsola help the reef ecosystem by allowing algae-eating fish to nestle inside of their horns. Gardens cluster together on the same reefs but tend not to socialize outside of breeding.
Rafts form when reefs are threatened or there is an overabundance of corsola. Some corsola will float to the surface link together, either with crooks in their horns or with the help of sargassum tied by fish hoping to curry favor with the new raft. The corsola will then drift off into the open ocean. As long as there is sunlight in the sky and calcium carbonate in the sea corsola do not care where they drift. Open oceans also lack many of corsola's predators. Miniature ecosystems can develop around corsola rafts, from algae that grows on them to creatures that eat the algae to apex predators that eat the algae-eaters.
Corsola does have predators that are able to break through their armor and eat the organic material inside. Toxapex can use acids and the strength of their suction cups to weaken the pokémon's shell and rip them open. Bruxish can simply smash the armor with their jaws. Outside of these pokémon corsola have no natural predators in Alola.
Certain pollutants can either kill corsola outright, kill their zooxanthellae, or cause their armor to weaken. Climate change is also warming the oceans. This makes zooxanthellae-killing heat waves more likely. Carbon storage in the oceans also results in acidification. One of the most direct consequences of acidification is a reduction in calcium carbonate levels, making it difficult for corsola to grow new armor or even to maintain what they've already built.
There are many stories of towns built on the backs of corsola rafts. Some of these communities even advertise themselves as places to see humans and pokémon coexist. These accounts have some basis in truth. Most of these towns are simply built on atolls or other reefs that reach above the surface. Settlements can be built on coral islands on atolls. The nearby reef will likely house corsola. The island itself is likely to contain small fragments of long-dead corsola. Others are groups of ships or other buoyant structures connected by planks. The anchors and regular seeding of rock attracts corsola rafts. The corsola, in turn, can be harvested for jewelry. During times of high coral prices these communities pop up along tropical shores.
There is a drifting town that floats throughout Melanesia. Rain barrels and extensive gardening provide for water and plants. Fish makes up the bulk of the diet. The town floats on the backs of corsola filled with air and then sealed with resin. The process is only performed on dead corsola. It would be fatal to a living one.
Husbandry
Corsola can survive on the trail with either an ultra ball or an aquatic habitat ball (lure, dive). They can occasionally be released for battle, practice, socialization, or other enrichment. Corsola can come to view trainers and teammates as part of their raft. This affection will be expressed by cuddling, especially by trying to hook their horns through necklaces, pockets, fur, or anything else that can be a tether. Corsola cannot be placed in a pool with toxapex, mareanie, or bruxish. Pokémon Center staff are prepared to deal with situations where predators and prey need access to the same pool.
It is best to keep corsola in one place whenever possible. A central tank or saltwater pool should be provided. If a pool is chosen it should be in a greenhouse or indoors with artificial lighting designed to mimic sunlight. In either case corsola do best in a tank with an already-established reef with hard corals and liverock. The tank should have a pH around 8.0 and a temperature between 75 and 85 degrees. There should be places for corsola to anchor themselves to the reef without causing too much damage. The tank should regularly be seeded with new shells to ensure that there is enough material to repair damage.
Corsola's photosynthesis is greatly impaired if they are coated in algae. They appreciate fish and invertebrates, pokémon or otherwise, that will clean algae off of them. If no tankmate is provided for this a human diver can do so. In tanks where the trainer cannot get into the tank but the corsola is still too deep to reach the pokémon can be trained to come to the surface for cleaning. Corsola on a reef are not particularly active or social but some basic training like this can be used to inspect for health problems or for bonding.
Beyond algae eaters corsola can tolerate almost any reef pokémon that will not actively eat them. Smaller fish and pokémon appreciate the ability to take shelter between corsola's horns. Colorful species can complement their aesthetics.
Illness
Corsola are capable of regenerating from almost anything, sometimes even forming more pokémon than there were at the start. Damage to the core will kill the individual, although more can form from the horns if left in a tank with no disturbances and ready access to material for armor. Whether the pokémon grown from horns are the same pokémon on a spiritual or mental level is disputed among scholars, psychics, ethicists, and priests.
Some chemicals can kill corsola. Powerful bleaches and other industrial chemicals should be kept far away from the aquarium. Some poison-types or particularly strong pokémon can kill corsola outright, even preventing the horns from spawning a new corsola. If corsola absolutely must be used in battle it should be kept far away from anything that can inflict permanent damage.
In high temperatures or when under great stress corsola will expel their zooxanthellae. This leaves them unable to create new food until conditions normalize. Prolonged heatwaves or sudden shocks on the reef can result in mass die-offs of corsola. In captivity there is usually time to correct the problem before death occurs.
Evolution
N/A
Battle
Corsola are reasonably durable and can learn a variety of useful utility moves such as whirlpool, toxic, and stealth rock. They get more out of the move 'recover' than most other pokémon. They are still not bulky enough to be used in high level play. They are decent on stall-focused teams for the first half of the island challenge but will quickly be unable to withstand enemy hits long enough to be useful. Corsola is best left to hobbyists, aquariums, and coordinators.
Galarian corsola (C. carus mortuus) has seen quite a bit of use on professional stall teams as it is nearly impossible to take out of a fight, has an even wider utility movepool, and can withstand far greater damage without permanently dying. Its evolution, cursola, is not fast or bulky enough to find a solid niche despite its power. Many trainers and leagues also find the use of incredibly powerful curses to be unsporting. Most corsola are retired or given away upon evolution.
Acquisition
Corsola can be found on and around most reefs in Alola. Their capture is currently restricted due to the ongoing decline in their numbers due to climate change, pollution, and a surge in toxapex numbers. Trainers wishing to acquire a corsola can buy one from a number of breeders and most aquarium specialty stores. Capture is legal on at least two reefs at a time. The allowed reefs rotate. Consult the DNR for more information.
Corsola can be acquired with a Class I license.
Breeding
Corsola can reproduce asexually from broken off horns. The tendrils within the horn will extend and allow the pokémon to slowly move across the environment. Small pieces of broken coral will be brought inside to a small stomach near the horn's central nervous system. Over time a small body will develop. A core will be formed inside. Then more rapid growth will begin.
Sexual reproduction is occasionally observed in reefs and common among rafts. The corsola will congregate on the surface before releasing gametes en masse. Females can release up to five thousand eggs during a spawning event. The eggs will hatch three days later and then begin building up their own bodies. As with most mass spawning events, mortality is extremely high among both eggs and newly hatched pokémon.
Spawning is difficult to induce in captivity. Corsola are usually fine with having their horns broken off, however. This can be used to obtain material for jewlery or for reproduction. Injured corsola will sometimes try to eat broken horns to regain material. The horn will need to be placed in a new tank with plenty of armor-building material. Once fully regenerated it can be reintroduced to the main tank.
Relatives
Corsola can be found in tropical waters worldwide. Some rafts will drift into temperate coastal areas in the summer and then go back to the tropics in the winter. Some scientists maintain that there should be as many as twelve corsola subspecies. The current consensus is that aside from the main species there is only one other subspecies.
The Galarian corsola is a result of human intervention in the natural world. In 1959 the Galar Chemical Company began manufacturing the laundry detergent Miragel. One of the chemicals used in the product's creation was released into the rivers of Galar and eventually ended up in the oceans. Almost all of the coral reefs around Galar died within seven years, bringing the corsola with them.
The corsola did not stay dead. Instead they began to move again even though they were pure white and devoid of zooxanthellae. No living tissue existed inside of them. The new corsola were merely armor shells possessed by phantoms. Galarian corsola mostly stuck to the reefs and periodically repaired their armor by breaking off some of the dead coral. They're food source was and is unknown. Sometimes one of these corsola would be too badly injured to repair itself. This would result in evolution into cursola, a phantom given semi-physical form with only a few pieces of coral to attach itself to. Cursola are all but immobile and have no armor to speak of. They are also able to weave some of the strongest hexes of any ghost type. The reefs of Galar are off-limits to human visitors to avoid curses from the coral ghosts. On occasion a bold documentarian or adventurer will venture into the old reefs.
The lucky ones do not live to tell the tale.