"Cockroach wasp venom blocks receptors of the neurotransmitter octopamine, which is involved in the initiation of spontaneous movement," according to the report. "With this blocked, the cockroach is still capable of movement, but is unable to direct its own body. Once the cockroach has lost control, the wasp drags its stupefied prey by the antennae to a safe shelter to devour it."
The red-and-black wasp is only known to live in Thailand. It has marked wings and "belongs to an ant-mimicking group of species with attractive coloration and rather bizarre habitus and probably also behavior," authors write in a 2014 research article published in PLoS One.
The Museum für Naturkunde, a natural history museum in Berlin, asked 300 visitors to pick the wasp's name from among four options: "Bicolor," after its red-black pattern; "Mon," after a local ethnic group where the wasp lives; "Plagiator," since it mimics, or "plagiarizes," ants; and "Dementor," described to visitors as "magical beings, which can consume a person's soul, leaving their victims as an empty but functional body without personality and emotions."
Researchers identified 139 new species in the area that includes Cambodia, Laos, Myanmar, Thailand and Vietnam. That figure includes 90 plants, 23 reptiles, 16 amphibians, nine fish and one mammal -- a bat with extra-large fangs.
Known as Hypsugo dolichodon, or the long-toothed pipistrelle, the long-fanged bat that researchers first described in 2014 uses its big teeth to chow down on insects with hard shells. The bat is found in Laos and Vietnam, although it's still not known what kinds of habitats it prefers. The bat could live in caves or in the forest, according to Tamas Gorfol, who helped discover the animal.
Another find included in the WWF report: The world's second-longest insect, Phryganistria heusii yentuensis, measuring 54 centimeters from tip to its back legs. The stick insect was found in Vietnam.
Since 1997, scientists have identified and described 2,216 new species from the Greater Mekong, according to WWF. But officials warned that the species' habitats are being threatened by dam construction, the international pet trade, deforestation and illegal poaching.
“We’ve only skimmed the surface of new discoveries in the Greater Mekong,” Carlos Drews, WWF's director of the global species program, said in a statement. “However, while species are being discovered, intense pressures are taking a terrible toll on the region’s species. One wonders how many species have disappeared before they were even discovered.”