New Species of 'Invisible' Fairyfly Insect Discovered and Named Tinkerbella

They may be called "fairyflies," but they certainly don't look like Tinkerbell. Researchers have discovered a new species that, despite its appearance, they've dubbed Tinkerbella nana.

Mymaridae, commonly known as fairyflies, can actually be found worldwide. They're one of about 18 families of chalcid wasps, which are known for their often-parastic natures. The family includes a tiny set of insects, including the world's smallest known winged insect, the Kikiki huna, which has a body length of only 155 micrometers. It also includes the smallest known adult insect, the wingless male of the Dicopomorpha echmepterygis, which is a miniscule 130 micrometers.

Because of their minute sizes, fairyflies are seldom noticed by humans. Their apparent invisibility and delicate wings is what has earned them their common name. Even their breeding is mysterious. While most of the fairyfly species are parasitoids of eggs of other insects, actually finding the host insects is difficult. The eggs are often laid in concealed locations, such as in plant tissues or in leaf litter or soil.

Now, though, researchers have announced that they've discovered a new species of fairyfly. Specimens were collected at the La Selva Biological Station, which is a lowland rainforest research and education facility owned and managed by the Organization for Tropical Studies in Costa Rica. Found in fairly young forest mixed with a primary forest, the specimens were all below 250 micrometers in length. Possessing tiny wings with long setae, the creatures beat their wings several hundred times per second.

You might wonder how it's possible for insects to evolve to be so small. The lead author of the paper detailing the creatures has an answer. "If something is physically possible in living things, some individuals of at least one species, extinct or extant, will likely have achieved it," said John Huber from Natural Resources Canada in a press release. "So the lower size limit, by water measure of size is chosen, was almost certainly already evolved-somewhere, sometime. If we have not already found them, we must surely be close to discovering the small insects and other arthropods."

The details of the insect are published in the Journal of Hymenoptera.