Ampulex dementor, commonly known as the dementor wasp, is a species of cockroach wasp native to Thailand, described in 2014 by Michael Ohl of the Museum für Naturkunde in Berlin, Germany. The species name was selected by visitors to the museum in an effort to raise awareness among the public of issues in taxonomy and the description of biodiversity.
A. dementor is colored in red and black. Its mandibles and most of its clypeus, prothorax, mesothorax, and posterolateral areas are all light red, while its abdomen and much of its head is black. Its wings are slightly yellow. It has long, slender legs, and a tubular petiole, as long as the tergum. Of about 170 species in the family Ampulicidae, Ampulex dementor is the largest. The length of females varies between 9.6 and 10.9 mm; the length of males is uncharacterized.
The wasp has an unusual behavior towards cockroaches. As it stings its prey, it releases a toxin into the victim's neural nodes. This toxin blocks the cockroach's octopamine receptors, leaving the cockroach alive, but docile and with impaired motility.[1] By prodding with its antennae, the predator then escorts its victim into the wasp's nest, where it can be dispatched more easily.[2]
At the time of the wasp's description, visitors to the Museum für Naturkunde (in which the species was described) were asked through pamphlet distribution, to choose between four names, the third of which was ultimately chosen:[2]