Creeping Cleanertree
A series of symbiotic relationships allows this hardy ant plant to survive in places where few others can.
Specialized ant trees adapted to grow in small cracks in solid rock, the carnivorous rockroots have diversified by 285 million years PE and spread to many varied rocky environments where little else can grow as a result of their ability to use their symbiotic ant colonies to collect nutrient sources for them in the form of animal prey and other organic detritus, which are broken down inside their stems by digestive enzymes. Many members of this genus favor sheer vertical cliffs, but as they have spread across the world, some are now epiphytes that grow on other types of trees - sometimes killing them and taking their place over time. They are almost all wind-pollinated plants and produce seedlings, rather than fruits or seed pods, which are dispersed by flying female queen ants as they leave to begin their own colonies. This allows rockroots to disperse intelligently; rather than rely on the randoms of wind or weather, they are guided to the ideal habitats in which they will have the best chance at growth, an advantage they have over all other plants in the hothouse age.
This arrangement is not perfect for the ants. In all species, most new colonies fail, because starting a new nest from scratch before their host plant is grown is difficult, requiring the new queen begin her nest in the more exposed rocky crack she plants the seedling in, and then to nourish its growth until it forms its first hollow shoot in which she can chew an entrance and dwell. This process may take as little as six week or as long as six months depending on the nutrition it receives, and during this time the ant queen and her growing offspring are vulnerable to weather and temperature. The different ant symbiotes of the rockroots all rely on sheer numbers to ensure some new colonies do survive, and these ants produce far more offspring for this purpose than need to survive to continue their species, which is typical for colonial insects as a whole. The plants, however, produce relatively few offspring, usually too few for every queen to take one on its maiden flight. This is because even if the original colonizing queen of a seedling dies, another will almost immediately take over the spot upon noticing it has become vacant, and so effectively adopt the abandoned plant. Most rockroots may go through several queens and starter colonies caring for them before they are large enough to reliably shelter a colony long-term. Yet once this vulnerable period has passed, both the plant and their hosts may live for many years. Rockroots are very long-lived plants with lifespans that can surpass a thousand years, and during such lives they will oversee many different colonies of ants, as new queens takeover abandoned nests over the years.
The creeping cleanertree is a descendant of the raptorial rockroot that has gradually spread from isolated inland boulders to the cliffs along the Serinarctan coast, and from there to near-shore rocky islands where, though there is abundant moisture in frequent rains, it rapidly washes away for there is no soil substrate in which to hold it or allow most plants to rake root. It is comparatively salt-tolerant versus its ancestors to endure oceanic salt-spray, exuding excess sodium as droplets of brine from pores in trunk, and its leaves are reduced to small, sharp needles that prevent water loss and damage from strong winds in its exposed habitat. To acquire water, the creeping cleanertree grows long aerial roots that dangle down as much as 25 feet from its branches; fuzzy along their length on a microscopic level, they serve to collect freshwater during the rains and rapidly absorb it; in the absence of this, they can wick it out of morning fog.
These rockroots are an interesting example of a carnivorous plant that does not any longer hunt. Though their ant symbiote is descended from a hunting species, it has now evolved a new and even more novel lifestyle upon its specialized habitat. The creeping cleanertree is a scavenger, consuming mostly already dead things; its ant is a cleaner, which removes waste in the form of droppings, broken eggs and dead juveniles from the nests of seabirds and tribbfishers which raise their young upon these isolated sheer cliffs out at sea, and so benefiting their survival.
The forager cast of the splendid housekeeper, the symbiote of the cleanertree, is a fairly large one centimeter in length and extremely long-legged, adapted to run long distances over the cliffs in search of distant food sources. It is also an exquisitely beautiful ant, with a brightly colored abdomen sporting a tapestry of red, blue and gold, as well as a vibrant yellow patch on the thorax and bright blue knees. Its vibrant patterns function as a signal to nesting animals of its good intent and distinguish it from various predator ants that hunt in most other parts of the world. Recognizing the unmistakable pattern of the cleaner, both seabirds and tribbats allow the ants to enter their nests and even climb into their own feathers or hair freely, where they also serve the very beneficial role of killing and removing parasitic mites and lice. Foragers take all that they collect back into the hollow stems of their host's trunk and deposit the neatly dismembered particles within specialized dump chambers therein where the plant digests them and breaks them down into nutrients. As in nearly all rockroots' ant symbiotes, the insects do not consume any of their gathered material itself and are fed exclusively upon fatty bodies produced by their host plant. Within the colony are smaller workers, brown and not distinctly marked, which maintain the nest itself and care for the larvae and the queen itself. As the foragers are so large, they are only produced by mature colonies with large plants in which to shelter and before that time the queen, who is not brightly marked but has wings and so is more mobile to avoid being injured by animals, must locate sources of food and bring them back to her seedling on her own. Queens of this ant species retain their wings for as long as a year after maturing for this reason, only shedding them when they at last have a large colony and the protection it entails.
Creeping cleanertrees are highly varied in size, and adult trees may measure as little as twelve inches across or grow to more than thirty feet, sprawling low over an entire rocky island. Their growth is dependent entirely on food supply, and plants which can take root within the busiest nesting colonies are always the best-fed and largest. Not only do cleanertrees grow best where animals nest in the highest concentration, but animals will preferentially choose to breed where there are the most cleanertrees, as these organisms greatly improve the fitness and survival of their offspring. The trees, for their part, are highly territorial and do not like to share their space or the limited supply of food. Different colonies within them do not recognize the other as allies and fight with hostility if their plants come too close, attacking each other's leaves with sprays of acid. It is so that while cleanertrees which grow on less fertile cliffs with little food stay very small and stunted, they survive at a much higher density than on rich cliffs where food is abundant, as the plants do not grow large enough to meet each other and fight as readily. Though productive nesting grounds grow huge, sprawling cleanertrees, there may be just one or two ancient individuals monopolizing the entire area, the result of centuries of battles over land rights, in which only the very strongest has prevailed. Once an adult tree has claimed such a site it will remain there for centuries, killing all new seedlings and claiming all of the island's resources for itself. Yet sometimes, for unknown reasons, a nesting colony will abandon a long-held cliff and such an old tree will be left to starve. For a very old stand, the process may take more than a decade as they slowly die off, unable to maintain themselves on the tiny amounts of nutrition that much smaller trees are able to. Vacated islands, their rocks blanketed by the dead, wind-twisted branches of a dead cleanertree, are not uncommon sights on the sea cliffs off Serinarcta. These skeletons of former kings eventually provide shelter from the wind for new seedlings, as smaller but hardier trees eventually take their place scattered around the remnants of the fallen giant.