The 113-year locust (thē/WUN-HUN-dred-an(d)-THUR(T)-tēn/yir/LŌ-kest) is a type of grasshopper that lays dormant for 112 years, and then, for exactly one day in the summer, erupts seemingly out of nowhere to swarm and devour their chosen foodstuff.
There are 112 different subspecies of the 113-year locust on record, and they cycle through periods of activity at a rate of one subspecies per year, with the exception of the 113th year. For example: subspecies 1 may be active in 1866, subspecies 2 in 1867, subspecies 3 in 1868 and so on until the 113th year in which no locusts swarm. Each swarm of locusts will feed on something different from that of the previous year. Luckily, records are complete enough that we can anticipate their arrival.
The locusts will swarm for one day, in a small area in Mishipeshu Province. The swarm is typically not larger than a half mile in diameter, but may be so thick with locusts that the swarm becomes visually impenetrable.
The swarming usually happens between the 8th-21st of June, but as the locusts seem to be operating on a lunar calendar, the swarming occurs in mid-July at irregular (but predictable) intervals. The first signs of the swarming are a loud buzzing sound just before dawn. The swarm erupts with the first rays of sun's light and ends abruptly at sunset.
The swarm never appears in the same exact place twice, but their appearance can still be predicted with some accuracy. If there is no foodstuffs of the appropriate kind where the swarm appears, it will travel toward the closest food source. Sometimes, the swarm will split into smaller groups if there are multiple food sources nearby.
Each of the 112 subspecies prefer a different food. Some are easily satisfied, with some preferences for such things as mammalian flesh, plant life, or air. Others have a more specialized diet and require eyes, grasses, freshly baked pastries, or hoop snake stingers. Yet another category feed on the esoteric, devouring intangibles like sunlight, mortality, love, time, or fear.
All attempts made to eradicate these vermin have been unsuccessful due in part to the lack of information about where the locusts actually go when dormant. Unlike other locusts, the 113-year locust does not simply burrow underground, but seems to wink out of existence entirely between cycles. Various theories have been offered regarding the nature of their disappearance, including suggestions that the locusts travel to another part of the world, another plane of existence, or even that they are not bound by the laws of linear time.
Tests have conclusively shown that a different subspecies of locusts is active each year of the cycle. Dissections have informed us that there is a marked difference between the digestive systems of those locusts that eat abstractions, and those that eat physical matter. Also, cryptozoologists have had some success marking individual locusts and tracking their appearance exactly 113 years after their last sighting. Legend has it that the missing 113th subspecies of locust fed on swarming grasshoppers and that it cannibalized itself to death. It is therefore possible that given time, a new subspecies will rise to take its place. Little is known about how the 113-year locust reproduce. There is no term for a juvenile. The collective noun is a swarm.
The swarm appears in a small area of very arable farmland in Mishipeshu Province and can travel from there. It is unknown where the locusts go when dormant.
For the most part, the locusts resemble the common American grasshopper, especially in size and shape. However, each sub-species is adapted to feed upon their preferred food souce.
Each subspecies feeds on one specific thing or category of things. They will eat ravenously until the swarm ends, flying or hopping to the nearest food supply, similar to grasshoppers.
The individual members of the swarm can be killed and used for spells and potions, although they are not any better for this purpose than the common grasshopper.
If you are unfortunately in possession of the preferred diet of the swarm, divest yourself of it and flee. The swarm is simply too large and fast to fight with. Otherwise, if the locust's appetite does not appear to be harmful, a person of good composure and patience can merely wait for the locusts to pass on their way.