For the first time, researchers have described a new species of praying mantis based on female genitalia – and not the male’s. Also, it’s named after Supreme Court Justice Ruth Bader Ginsburg. The leaf-dwelling Ilomantis ginsburgae of Madagascar is described in Insect Systematics & Evolution this week.
Female genitalia have long been overlooked as a way to delimit new species. Since the 1920s, male genital structures have been a standard in classifying insects at the genus and species levels. But defining species can be especially hard when limited to a few, poorly known characteristics. Having traits from females in addition to males would make identifications easier. Not to mention, it would reduce the chances of mistaking a specimen of a different sex as a specimen of a never-before-seen species.
To investigate the use of female genital characters in taxonomy, Sydney Brannoch and Gavin Svenson from the Cleveland Museum of Natural History examined two Afrotropical mantis genera that have an unstable taxonomic history: Ilomantis and Nilomantis. In the last century, Ilomantis was thought to be the same as Nilomantis, but it was then reestablished and then re-synonymized multiple times. The team examined 30 praying mantis specimens housed in three museums in Paris, California, and Ohio. In addition to geographic distribution and dozens of external measurements, the researchers also focused on genital characters of both sexes.
Female genital structure of Ilomantis ginsburgae. Rick Wherley/Cleveland Museum of Natural History
One of the specimens they examined was collected in Madagascar in 1967. It has a similar look as other leaf-dwelling praying mantises: green color, flattened body, conical eyes, and broad wings with vein patterns like that of leaves. Based on their observations of the female genitalia, the team resurrected Ilomantis as a valid genus that’s separate from Nilomantis, and they found enough diagnostic differences to warrant a new species. They named it Ilomantis ginsburgae.
The new species honors Ruth Joan Bader Ginsburg, an associate justice of the U.S. Supreme Court, "for her relentless fight for gender equality, as well as for her sartorial appreciation of the jabot," the lacy, ornamental frill at the front of a shirt (or robe). It’s reminiscent of the mantis’s neck plate, "a diagnostic character that embodies this judicial accessory," the authors wrote.
"This species description of Ilomantis ginsburgae is novel since it relied heavily on the features of the female genitalia," Brannoch said in a statement. "As a feminist biologist, I often questioned why female specimens weren't used to diagnose most species. This research establishes the validity of using female specimens in the classification of praying mantises. It is my hope that our work not only sets a precedent in taxonomy but also underscores the need for scientists to investigate and equally consider both sexes in other scientific investigations."