Though it looks like a spider, has a web like a spider and moves like a spider, it’s not a spider. It’s actually a decoy built by a newly-discovered species in the Cyclosa genus.
When biologist Phil Torres was leading a group of visitors into a floodplain in Peru, he saw a white inch (2.5cm) long spider sitting its web. Its flaky appearance, seemingly covered in fungus, suggested it had been dead a while – until it started moving. It wasn’t until Torres got closer that he realized the illusion. The actual spider, only 5mm long in body length, was sitting above the decoy and shaking the web to create the illusion of movement.
The spider seems to be a completely new species, but its sculpting abilities have led experts to place it in the genus Cyclosa. Spiders in this genus are known to use debris in their webs to attract or confuse prey, but haven’t been seen to make anything as detailed as these decoys. The web-shaking behavior is also new. However more observations are needed before it can be declared a new species, as there is always the chance that this is a named spider engaging in never-before-seen behavior.
Photo credit: Phil Torres.
Sources (where several more photos are available)