Many times, when new species are discovered, the characteristics that set them apart can only be appreciated by scientists. That isn't the case with the Ceratogyrus attonitifer tarantula, however – the thing has a long, soft horn protruding out of its back, and nobody knows why it's there.

A member of the existing baboon tarantula family, C. attonitifer was first discovered when several female specimens were collected between 2015 and 2016 in the miombo-tree forests of central Angola. They were gathered by scientists taking part in the National Geographic Okavango Wilderness Project, which is aimed at exploring the biodiversity of Africa's Okavango Delta.

Although some other baboon spiders do also have "back horns," the appendages are much harder and shorter than that of the newly-classified species. In all cases, the purpose of the structure remains unknown.

Thanks to information provided by local indigenous people, however, some things are known about C. attonitifer's behaviour. Known as "chandachuly" by tribes in the area, the spider is said to prey mostly on insects, with females enlarging existing tarantulas' burrows instead of digging their own. Additionally, its venom is reportedly not dangerous to humans, although fatalities have occurred from bites getting infected.

A paper on the findings was recently published in the journal African Invertebrates. And the Latin name "Ceratogyrus attonitifer," incidentally, roughly translates to "bearer of astonishment."

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