You might be forgiven for thinking there are some cotton plants sprouting up in the centre of this leaf. In fact, these tiny fluffballs are Honduran white bats (Ectophylla alba), native to parts of Central America.
They reminded me at first of pygmy puffs from Harry Potter, except these are real. The bats grow to between a whopping 3.7cm - 4.7cm and are related to a species of bat known as the 'tent-making bat'. This is because they make tents. (The logic! It astounds!)
Honduran white bats live in small colonies on the underside of large leaves of the Heliconia plant. They make a protective 'tent' by using their teeth to cut along the midvein of a leaf, causing it to fall over slightly and form their shelter. This protects them from predators and the elements. And despite being white, the leaves provide them with excellent camouflage, because sunlight filters through the leaf and tints their fur green.
Mostly, however, they just hang around being really, really cute-looking.
Thanks to voguelady at Milk and Ink for bringing these to my attention.