Discover takes a close look at a monster smaller than the tip of a ballpoint pen. It’s the world’s smallest fly, a kind of fly called a phorid, and its babies eat the brains of tiny ants:
When the maggots hatch, they move towards the ant’s head, where they gorge upon the brain and other tissues. The ant stumbles about in a literally mindless stupor until the connection between its head and body is dissolved by a enzyme released from the maggot. The head falls off and the adult flies burst out.
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Brian Brown from the Natural History Museum of Los Angeles County has just discovered a Thai phorid that’s just 0.4 millimetres in length. It’s the world’s tiniest fly, small enough to sit comfortably on the eye of a common housefly. It’s easily small enough to fit inside the head of even the smallest acrobat ant. It just goes to show that there is no way of truly escaping from parasites. If you evolve a miniscule body, they will shrink even further in pursuit.
Though tiny, these little flies are twice the size of the world’s smallest insects – a species of wasp that lays eggs on a slightly larger creature to do horrifying things. In their case, the victim is a thrip… and the wasps are smaller than amoebas.