Wasps may turn ladybugs into zombies with viral weapons

ladybug

Parasitic wasps use Coleomegilla maculata and other lady beetle species, like the one pictured above, as egg incubators and then turn them into stoic, mindless guards for cocooning pupae. Their secret weapon may be an RNA virus that triggers an immune response in the ladybug's cerebral ganglia.

Keith Marshall/Flickr (CC BY 2.0)

Parasitic Dinocampus coccinellae wasps lay their eggs inside spotted lady beetles (Coleomegilla maculata). The pupae hatch and spin cocoons, and the ladybugs become zombielike bodyguards. A virus that lives in the wasp’s egg sacks does the actual zombification, researchers report February 11 in Proceedings of the Royal Society B. 

Researchers found that a symbiotic RNA virus replicates in the host’s brain tissue, which triggers paralysis and tremors. Once ladybugs clear the virus from their system, they behave normally again. Rather than deploying a neurotoxin, the wasps could be using this virus as a biological weapon against their hosts, the authors suggest.

Editor’s Note: This post has been updated to reflect that the lady beetle pictured above belongs to an unconfirmed species.

Helen Thompson is the multimedia editor. She has undergraduate degrees in biology and English from Trinity University and a master’s degree in science writing from Johns Hopkins University.