When you think of predators, you likely imagine big animals with sharp claws or teeth, like tigers or sharks. Over 100 million years ago, however, a tiny yet freakishly fearsome predator impaled its prey with scythe-like jaws.
While investigating a large collection of fossil insects at the Museum of Zoology at the University of São Paulo, researchers in Brazil realized that a 113-million-year-old fossil represents a new ant species and might be the oldest ant specimen known to science. The fossilized ant, named Vulcanidris cratensis, is a member of the extinct ant subfamily Haidomyrmecinae. Appropriately dubbed “hell ants,” Haidomyrmecinae ants existed during the Cretaceous period (145 million to 66 million years ago) and are known to paleontologists for their vicious and highly specialized jaws.
“Our team has discovered a new fossil ant species representing the earliest undisputable geological record of ants,” Anderson Lepeco, a researcher from the Museum of Zoology at the University of São Paulo, said in a Cell Press statement. “What makes this discovery particularly interesting is that it belongs to the extinct ‘hell ant,’ known for their bizarre predatory adaptations.”
Lepeco co-authored a study detailing the discovery, published Thursday in the journal Current Biology. He and his colleagues studied the hell ant, preserved in limestone, via a 3D imaging technique called micro-computed tomography, which reveals the insides of objects. According to their analysis, the ant had impressive mandibles (mouth parts) that poked forward, parallel to the shape of the head in front of the eyes, which were likely used to pin down prey. In contrast, the mandibles on modern ants move sideways.
“Finding such an anatomically specialized ant from 113 million years ago challenges our assumptions about how quickly these insects developed complex adaptations,” Lepeco explained. “The intricate morphology suggests that even these earliest ants had already evolved sophisticated predatory strategies significantly different from their modern counterparts.”
Furthermore, the researchers concluded that the specimen was closely related to other previously discovered hell ant species preserved in amber in Myanmar. Since the Vulcanidris cratensis came from the Crato Formation—a fossil hot-spot in northeastern Brazil—this suggests that by 113 million years ago, Haidomyrmecinae ants had already spread all over the world.
“When I encountered this extraordinary specimen, we immediately recognized its significance, not only as a new species but as potentially the definitive evidence of ants in the Crato Formation,” Lepeco added. “This finding highlights the importance of thorough examination of existing collections — private or in museums — and brings a spotlight to Brazilian paleontology and the underexplored fossil insect fauna of the country.”
The study ultimately reveals that ants had already diversified and expanded across the world 113 million years ago, shedding light on the evolution of one of the most successful insects on the planet.
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