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SCP-XXXX
Clearance Level: 4
Threat Class: 7
Object Class: Keter
Current Location: Site 54
Containment Procedures: All known instances of SCP-XXXX are to be contained within a sound-proofed enclousure at Site 54, made to resemble a subterranean cave system. The enclosure's background noise frequency may not exceed 4 mHz. To prevent unauthorized reproduction, SCP-XXXX's abdominal barbs are to be cut back once every four months. They're to be fed a special vitamin and protein slurry once a month. Feeding them live food will result in disciplinary action, up to demotion of clearance and a hearing before the 05 Council. To date, no further testing involving SCP-XXXX is permitted. Those stung by an instance of SCP-XXXX shall be immediately terminated, as per Ethics Code 2-45-C.
In the event of a Containment Breach, simple mega-phones can be used to completely incapacitate them for an hour.
Description: SCP-XXXX is a species of subterranean arachnid, on average reaching 54cm in length. They were first found in Vietnam in 1955, by Foundation Operatives infiltrated into the United States Armed Forces. To date, the Foundation has seven specimens under heavy containment.
SCP-XXXX entirely lacks pigmentation, and has eyesight roughly comparable to that of a bat. By undiscovered mechanisms, they can detect noises at frequencies as low as 7mHz, aiding them greatly in hunting. Their exoskeleton is covered in barbed quills, which they can launch from their body at will. They've has been observed utilizing them for both hunting and self-defense. Like many arachnid species, SCP-XXXX can create webs, who's tensile strength exceeds that of high-grade titanium. Through undiscovered mechanisms, the subjects can sense sounds as low as 7mHz, which they utilize to great effect when hunting. It does, however, make them vulnerable to loud noises, with sounds exceeding 10Hz visibly aggitating them. Anything greater than 50Hz will drive them into sensory overload, inducing a catatonic state for as long as 1.5 hours.
To date, cognitive tests have shown that SCP-XXXX have memory encoding, problem-solving skills, and a general capacity for learning on-par with that of adult humans. There are currently 7 individual instances held in captivity by the Foundation. All known specimens have been female, with genetic tests suggesting they reproduce through parthenogenesis.
SCP-XXXX's sex organs have evolved into long, hollow barbs, allowing them to implant fertilized eggs into an endothermic host. When laid in the brain-stem, the eggs subtly change the brain chemistry of said host, causing such symptoms as heightened aggression, changes in eye-color (usually black scleras with white irises), increased strength and agility, and the shutting down of higher brain functioning. Such subjects, designated as SCP-XXXX-1, act as worker drones, hunting for food and new hosts for SCP-XXXX. It takes about four months for the eggs to hatch, at which point the young will devour their host from the inside out. Tests have shown juveniles can completely strip a human host of flesh within three hours.
SCP-XXXX can anomalously detect sounds as low as 7mHz, over a maximum range of 4 km. They utilize this when hunting prey their drones can't take down themselves, utilizing a combination of pursuit hunting and ambush tactics. Most prey are only taken down when they're no longer able to put up a fight.
To date, the extent of the population of SCP-XXXX is not known, though instances have been found across Eurasia and the Americas by Foundation Operatives. Only seven have been successfully captured. Given that one instance could lay up to 15,000 eggs once every three weeks, however, it's calculated that an infestation of the planet's surface could result in a Class 3 Extinction Event. Given the rate of human technological progression and increased population sizes, this is becoming an increasingly urgent concern of the Foundation. Whereas human activity generally generates 4.7mHz of noise, should we cross into SCP-XXXX's range of hearing, invasion may become inevitable. The 05 Council is currently discussing possible contingency plans, should this come to pass.
