The first video of a parasitic wasp attacking an underwater caterpillar

Very few species of parasitic wasps can be considered aquatic. When searching for potential hosts or living as endoparasitoids at the end of aquatic hosts during their larval stage, less than 0.1% of the species we know today enter the water.

In the subfamily Microgastrini (Family Bridae cida nide), only two species of aquatic caterpillars have previously been reported to be aquatic based on the parasitism of moth caterpillars. However, no one who dives into the water knows.

Recently, during his research work in Japan, Dr. of the Canadian National Collection of Insects. Jose Fernandez-Trina found the first microgastrin parasitic wasp to dive into the water for a few seconds to attack the caterpillar and out, and recorded the hosts, so that they lay their eggs inside it before releasing them back into the water.

Interestingly, the wasp, which in the open access case was described as new to the science species, is a peer-reviewed scientist Journal of Hymenoptera Research, Microgaster Ster Godzilla, surprisingly named, because getting out of the water is reminiscent of the scientists of Godzilla, the Japanese iconic fantasy monster.

In the video, female wasps can be seen floating on floating plants as they search for hosts, especially larvae of the moth species Allophila turbata, which form portable cases from fragments of aquatic plants and live close to the water surface inside them. Once the wasp finds one of these cases, it will first look around again with its antennae. Eventually, it forces the larva out of the case and quickly parasites it by inserting its ovipositor. In some cases, to find and pull the caterpillar out of its case, the wasp has to be completely submerged for several seconds. To do this, the species has evolved into elongated and strong curved trawl claws, which are used to grip the substrate as it enters the water and is in search of hosts.

Speaking of the odd choice of name for the new species, Dr. Jose Fernandez-Triana explains:

“The reasons why we decided to name Godzilla for the wasp species are interesting. First, being a Japanese race, it reverently honors Godzilla, a fictional monster (kaiju) that became a symbol after the 1954 Japanese film of the same name. And many subsequent remakes. It has become one of the most recognized symbols of popular Japanese culture around the world. Second, the wasp’s parasitic circle bears a slight resemblance to the kaiju character, in the sense that the wasp suddenly emerges from the water to parasitize the host. Similar to how it emerges from the same water, the third, Gadzilla, often with Motera, is associated with another kalju, usually represented as larvae (caterpillars) or adult moths. See, we have to justify the choice of name. We have biological, behavioral and cultural reasons. Of course, enjoy it and a little more, because it is also an important part of life and science! “

Beyond the unusual behavior and funny names, Dr. Fernandez-Trina seeks to emphasize the importance of multidisciplinary work and collaboration. The team publishing this paper briefed each other at the International Meeting on Biological Control (5th International Entomophagus Insects Conference, 2017 in Kyoto, Japan).

“I was very impressed with the many presentations by Japanese standard students, including video recordings of parasitic wasp biology. As a classifier, I have always been impressed by the quality of research done by colleagues in other fields. In this case, we saw an opportunity to study wasp To combine efforts, and when we found out that it was a new species, we described it together, including adding filming behavior to the original description. In general, the classification descriptions of the parasitic wasp are based on dead specimens, very little about its biology. With details – often none but. Thanks to my biocontrol colleagues, we will be able to add more information to what is known about the new species described. Hopefully we will be able to continue this collaborative and joint approach to future studies.