Usually, throw the internet an image of something you can't identify and it's only a couple of minutes until you're bombarded with people pointing out how dumb you are. Not so with this mystery cocoon, though — because nobody can work out where it comes from.
First spotted by Troy Alexander in Peru, he calls it a "maypole with a horse corral". Since, it's been posted on Facebook and Reddit, captured the imagination of entomologists and amateur bug-spotters, and... still nobody really knows where it came from.
Alexander claims he spotted several, around the Tambopata Research Centre, where he was staying. There are bigger pictures to study if you think you recognise it; any ideas where it came from, though? [New Scientist]
Image by Troy Alexander/Tambopata Research Centre