The German scientists who discovered this new species of ant in the Philippines gave it the name Cardiocondyla pirata because the blackish stripe that crosses the female’s eye is “reminiscent of a pirate’s blindfold,” they write in Zookeys. To me, though, it looks more like the insects took advice from the makeup artists behind Captain Jack Sparrow‘s heavy eyeliner.
The ants are the only ones known in the world to have this coloring, the researchers note in their paper. They discovered the species while searching for another member of the genus in which the males show great diversity of shape and behavior. During their search they came across these other ants “in the cleavage of big stones in a shady streambed,” study coauthor Sabine Frohschammer of Universität Regensburg said in a statement. “Due to the darkness of the rainforest and the translucent body parts of the tiny ants, they were nearly invisible. Under bright light and a magnifier we detected the nice stripe across the eyes and therefore always referred to these species as ‘the pirates,'” she said.
The purpose of the stripe is still a mystery. It probably doesn’t serve as a sexual signal to males of the species. Their vision is poor, and they rely more on chemical and tactile cues. And when they hook up, it’s completely dark. It’s more likely, the researchers say, that the stripe and other coloring in the female help to confuse a predator, perhaps giving the impression that the ant is actually two insects (one of the segments closer to the rear is nearly translucent). But until the scientists find a predator that has good enough vision to see the details on this ant, the purpose of the pirate’s eye stripe will remain just a guess.
Image credit: Bernhard Seifert