Fungus gnats (Bradysia species) – also known as dark-winged fungus gnats, are small, mosquito-like insects often found in homes and offices, usually in the vicinity of houseplants. The larvae that hatch are legless, with white or transparent bodies and shiny black heads. From the first glimpse you’ll notice they’re not the prettiest sight, but what they lack in looks, they make up in cleverness.
The fungus gnat larvae are incredibly vulnerable when alone; they’re puny, non-poisonous and practically at the mercy of predators – basically anything larger than them. To survive, the larvae have adapted a group behavior in which they join together by the hundreds to form a slimy, moving mass. The video embedded in this post illustrates this behavior. At first, you might be fooled to think you’re watching a snake (a two-headed snake?), but once the video zooms in all hell breaks loose.
While this instance of fungus gnat larvae behavior is very clever (or grouse), they’re consider serious pests and can cause severe damage to both houseplants and commercial crops. Some fungus gnat larvae are known for their propensity to feed on the roots and lower stem tissues of plants. These feeding habits stunt and might kill affected plants.