There can be few more unpleasant wake-up calls than being ripped from your resting place by a parasitic wasp, hellbent on stuffing you with its unhatched offspring, but that is the unfortunate reality for larvae of the moth species Elophila turbata. Shielded underwater, this caterpillar perhaps thought it was safe from aerial predators, but a new species of parasitic wasp is one of a very small number of aquatic wasps known to science. The feisty new species has been named Microgaster godzilla by a team of researchers studying it in Japan and whose findings were published in the journal Hymenoptera Research.
Of the parasitic wasps known to science, some of which turn their victims into zombies, less than 0.1 percent have been observed entering the water in pursuit of a host for their offspring. These endoparasitoids stuff their victims with eggs that will hatch, leaving the larvae to feed off of and live within their unlucky host.
The new species is one of only three within its subfamily, Microgastrinae, known to be aquatic, with all three targeting the aquatic caterpillars of moths in which to house their young. However, Microgaster godzilla is the only one that’s been observed actually diving in, staying underwater for several seconds at a time.
Our little water baby was discovered by Dr Jose Fernandez-Triana of the Canadian National Collection of Insects who, along with colleagues, was the first to catch the diving act of this unusual parasitoid wasp on camera. Its blockbuster name Microgaster godzilla was inspired by the wasps’ emergence out of the water, which reminded the team of Japan’s iconic Godzilla who emerged from the ocean to save the day.
The first-of-its-kind footage shows the female wasp stalking across some floating vegetation in search of a host. After spotting a larva of the moth species Elophila turbata, which shields itself in a mobile home made of plant fragments, she dives in. The wasp then pokes the caterpillar’s protective case until the poor tenant is forced out, where it’s quickly stuffed with an egg and the wasp heads on its way. This amazing underwater hunting strategy is facilitated by the wasp’s hind claws, which have adapted to be curved and very strong, perfect for gripping surface plants while grappling with an unyielding host.
Next time you find yourself cursing your alarm clock, just think how much worse it could be.