This praying mantis inflates a strange pheromone gland to lure mates

Praying mantises — with their angular options, big eyes, and centaur posture — typically appear a bit alien. But researchers have just lately discovered one mantis species that takes this otherworldly high quality to the subsequent degree: Females of this species have an inflatable pheromone gland that protrudes from the again of the stomach like an inexperienced, Y-shaped balloon. 

This odd organ is in contrast to something seen in mantises earlier than, researchers report online April 21 within the Journal of Orthoptera Research.

In October 2017, herpetologist Frank Glaw was shifting by the nighttime rainforest in Amazonian Peru on the Panguana analysis station, looking for amphibians and reptiles. His flashlight handed over a brown, leaf-mimicking mantis (Stenophylla lobivertex) within the tangle of vegetation, and he noticed “maggotlike” buildings protruding from its again. Those buildings had been shortly sucked again contained in the insect after the sunshine hit it, says Glaw, of the Bavarian State Collection of Zoology in Munich, Germany.

Glaw was reminded of “parasites that eat the animal from the inside,” having seen such fatally parasitized bugs earlier than. With the assistance of Christian Schwarz, an entomologist at Ruhr-University Bochum in Germany, and observations of some feminine specimens in captivity, the staff found out that the mantis was no parasite-riddled vessel. 

When left undisturbed in whole darkness, the feminine mantises extrude a pronged construction inflated with physique fluids, roughly the hue and luster of polished jade. It seems to be an extremely modified gland for producing pheromones — chemical alerts that help female insects attract mates (SN: 5/13/15). 

Other mantises have easy, noninflatable glands which might be situated in the identical part of the stomach as S. lobivertex’s bifurcated contraption.

This mantis species is never encountered by researchers and is perhaps thinly unfold all through the rainforest, so finding receptive mates might be significantly difficult. The researchers assume a big, protrusible pheromone gland with a lot of floor space might be a workaround, more effectively dispersing pheromones to be detected by the antennae of would-be suitors.

“It is a kind of chemical ‘dating app’ in the jungle,” says Glaw, noting that the observations “emphasize the importance of pheromones in [the mantises’] reproduction in a vivid manner.”

Females in another mantis species are identified to show a pink, patchlike gland when doing their chemical name for mates, says Henrique Rodrigues, an entomologist on the Cleveland Museum of Natural History who was not concerned with this analysis. 

“I can easily see something like that being the precursor of the protrusible gland,” says Rodrigues. He notes that since males have skinny, hairlike antennae, “the other way to increase the odds of mate finding would be for females to increase the amount of pheromone released.”

Glaw thinks it’s probably that related glands may exist within the different two species of Stenophylla, and presumably different mantises. “If this organ is really an important tool to improve the finding of mates,” he says, “it would be an advantage for many other mantis species as well and might be more widespread.”