The first thing to understand about velvet ants is that they are not, in fact, ants. They’re wasps, some of which are wingless, and are named in part for their fluffy exteriors.

About the size of a board game die, one species of velvet ant is known for its distinct black and white markings, which dazzle the eye as the creatures scurry across tropical savanna and a dry shrub desert in Brazil called the Caatinga.

Among national universities, Princeton was ranked No. 1 again, followed by the Massachusetts Institute of Technology and Harvard. Stanford, which tied for third last year, fell to No. 4. U.S. News again judged Williams College the best among national liberal arts colleges. Spelman College was declared the country’s top historically Black institution.

It “looks like magic,” said Vinicius Lopez, an entomologist at the Federal University of Triângulo Mineiro in Brazil who studies insect coloration. The effect makes them easy to lose sight of, he said with the help of a colleague who translated his remarks to English. It is perhaps why some Brazilians refer to them colloquially as sorcerer ants.

A team of scientists led by Dr. Lopez recently found that the black parts on female velvet ants were actually ultrablack — so matte that they absorbed nearly all visible light. The discovery, published in the Beilstein Journal of Nanotechnology this month, makes this particular species of velvet ant, Traumatomutilla bifurca, the first known insect among Hymenoptera — the group of animals consisting of bees, wasps and ants — to display such a striking shade.

“We have never seen this kind of color in the dragonflies or bees or beetles we have analyzed,” said Rhainer Guillermo-Ferreira, another entomologist at the Federal University of Triângulo Mineiro and an author of the paper.

In nature, some blacks are blacker than others. There’s your run-of-the-mill black, which is caused by the presence of melanin and displays some sheen, like the feathers on a crow. Then there’s ultrablack, sometimes called superblack, a shade achieved by microstructures that swallow nearly all of the light hitting a surface.

We are having trouble retrieving the article content.

Please enable JavaScript in your browser settings.

Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.

Thank you for your patience while we verify access.

Already a subscriber? Log in.

Want all of The Times? Subscribe.ps88