A species of tarantula that was recently discovered in Angola has something in common with the mythical unicorn — a prominent “horn.” But in the spider’s case, the horn is growing from the creature’s back.

The unusual arachnid belongs to a tarantula group known as horned baboon spiders. But in all other known species in this group, the “horn” is short and hardened. In the new species, however, the structure is elongated and soft, researchers wrote in a new study.

They collected eight individuals of the newfound species — now named Ceratogyrus attonitifer — from woodland habitats, during surveys conducted in southeastern Angola in 2015 and 2016. Its species name is derived from the Latin root “attonit,” which means “astonishment,” reflecting how surprised the scientists were to discover the remarkable arachnid, the study authors reported.

Dense fur made of short, black hairs covers much of the tarantulas’ bodies, which measure 1.3 inches (34 millimeters) long, on average. The long, floppy horns extending over the spiders’ backs are in some cases longer than their carapaces (the back portion of their bodies), the scientists wrote. While the base of the horn is hard, the rest is soft and “bag-like” in the living spiders; in preserved specimens, it shrivels up and turns darker.

The horn is both astonishing and mysterious, as scientists have yet to learn what the spiders use it for, according to the study.

source livescience.com