Scientists have discovered in Ecuador a new species of parasitic wasp that turns social spiders into zombies – that is, manipulating the arachnid to leave its colony.
A study, published in Ecological Entomology, discussed how the Zatypota wasp, a newly discovered species, can make the Anelosimus eximius spider be obedient to its orders. Although this isn’t the first time experts have noticed the zombie behavior, this new case is more complex, researchers pointed out.
Wasps’ Unusual Behavior
“Not only is this wasp targeting a social species of spider but it’s making it leave its colony, which it rarely does,” author Philippe Fernandez-Fournier explained.
Fernandez-Fournier was in Ecuador examining the social spiders Anelosimus eximius, which are known to live harmoniously in a colony and has an impeccable teamwork when it comes to catching prey. However, he observed that some of these insects had been infected with parasitic larva and had moved away from their colony.
After these infected spiders move out of the colony, they started spinning enclosed webs, much to the surprise of Fernandez-Fournier. The incident, described as “odd” by the researcher, was only the beginning. When the scientist took the cocoon for a closer look, what came out from the silk was a wasp.
The study’s coauthor, Samantha Straus, said that although wasps are generally “elegant looking and graceful” creatures, they are merciless. This was after they found out what these are capable of doing to social spiders.
It turned out that female wasps lay eggs into the social spiders. When these hatch, the larva eats the host until it grows larger. The unfortunate arachnid, which now is like a zombie, then heads out of the colony and start making a cocoon for the larva.
What’s worse is that after the spider does all the work, it waits until it is eaten by the larva. Afterwhich, the larva stays in the cocoon and nine to 11 days later, it will come out.
On Wasps Attacking Social Spiders
This is unusual as wasps had been known to target solitary spiders and not the social ones. Moreover, Straus said that this behavior was far more “hardcore” than what was earlier established as wasps can take over the spiders’ actions.
As to why wasps are suddenly attacking social spiders, the researchers believe that it is precisely because of the colony that can offer more food for them. Experts also said that the larger the colonies are, the more these are targeted by wasps.