Maybe the bone house wasp should be called the "house of horrors wasp."
Deuteragenia ossarium is a type of Pompiid wasp, a group that's often called "spider wasps" or "tarantula hawks" for their propensity to pounce upon and immobilize giant spiders with paralyzing and painful venom. According to one entomologist, the debilitating sting feels like "dropping a running hair dryer into your bubble bath."
But adult spider wasps don't eat spiders, they subsist mainly on nectar; instead, they drag the paralyzed spider back to its nest, lay an egg on top of it, and wrap it up like a cocoon. The developing wasp larvae eat the frozen (but still alive) spider as they mature.
But scientists already know this about spider wasps. What surprised the researchers that discovered the bone house wasp in a nature preserve in Jiangxi Province, China, was that their nests were filled with ant corpses.
"The first time I saw it, I thought maybe I wasn't seeing it clearly," said Ecologist Michael Staab, lead author of a new study on the wasp, published this week in PLOS ONE. "But then I found 10 to 15 more nests."
Further research helped explain why the ants were there.
Spider wasps have few predators, their sting being insanely painful, but they do have a petulant invader to deal with, smaller parasitic wasps. Staab and his colleagues found the spider wasps with more dead ants had smaller rates of parasite infestation.
Researchers concluded the bone house wasps have adopted a technique similarly used by other animals called "anting," whereby ants are rubbed on the body to take on their musk. Ants prey on parasites, so the chemical footprint and scent of ants must ward them off.
It all makes the bone house wasp not only terribly frightening, but also rather ingenious.