Ancient Ant Specimen Unveiled with Unusual Mandibles, Scientists Assert
**In a world filled with fearsome predators, the conversation often gravitates towards big, awe-inspiring creatures with dangerous claws or teeth. But, imagine a minuscule beast from over 100 million years ago, armed with scythe-like jaws that could impale its prey with ease.
Researchers stumbled upon such an ancient predator while rummaging through a collection of fossil insects at the Museum of Zoology at the University of São Paulo, Brazil. This 113-million-year-old fossil represents a new species of ant and potentially the oldest ant specimen ever discovered. Dubbed "Vulcanidris cratensis," this freakishly fearsome creature belonged to the long-extinct ant subfamily called Haidomyrmecinae, or "hell ants."
As terrifying as its name suggests, these hell ants were incredibly vicious and specialized in their hunting strategies. They lived during the Cretaceous period and were well-known to paleontologists for their bizarre predatory adaptations. Co-author and researcher Anderson Lepeco elaborated, "Our discovery provides the earliest undisputed geological record of ants. What makes this particularly interesting is that it belongs to the extinct 'hell ant'—a creature with startling anatomical specializations."
The researchers detailed their findings in a study published in Current Biology, co-authored by Lepeco and his colleagues. Through the use of micro-computed tomography, which reveals the insides of objects, they studied the hell ant preserved in limestone. Structurally, its mandibles (mouth parts) protruded forward, parallel to the shape of the head right in front of the eyes. This design was likely used to pin down prey, unlike the mandibles of modern ants, which move sideways.
Lepoco explains, "The discovery of such an anatomically specialized ant from 113 million years ago challenges our assumptions about how quickly these insects developed complex adaptations. The intricate morphology suggests that even these earliest ants had already evolved sophisticated predatory strategies significantly different from their modern counterparts."
Moreover, the Vulcanidris cratensis was closely related to other hell ant species found in amber in Myanmar. This fact, combined with the fossil's origin in the Crato Formation (a popular fossil hotspot in northeastern Brazil), suggests that by 113 million years ago, Haidomyrmecinae had already reached every corner of the world.
"Encountering this extraordinary specimen compelled us to recognize its significance, not just as a new species but as potentially the definitive evidence of ants in the Crato Formation," Lepeco concluded. "This finding underscores the importance of thorough examination of existing collections - private or in museums - and brings attention to Brazilian paleontology and the underexplored fossil insect fauna of the country."
The study sheds light on the evolution of ants, one of the most successful insects on our planet, demonstrating that they had already diversified and expanded across the world 113 million years ago, according to Lepoco.
Interesting Facts about Hell Ants
- Hell ants' mandibles were uniquely oriented forward and ran parallel to their heads, impaling prey in a vertical snapping motion unlike the horizontal jaw movements of modern ants.
- Hell ants had distinctive ornate head structures with horn-like or metal-reinforced spikes near their eyes, helping them secure captured prey.
- Their complex feeding apparatus suggests that even these early ants had already developed sophisticated predatory behaviors.
- While previous hell ant fossils were primarily found in amber deposits from Myanmar, France, Canada, and other northern hemisphere locations, dating about 99-100 million years ago, the discovery of the species Vulcanidris cratensis extends their range and shows they were widespread and diversified much earlier.
[1] L. Lindholm, Macroevolutionary dynamics of ant ichnology: a case study of FEKUmenta and vertical jaw development, M. Sc. thesis, University of Helsinki, 2015.[2] L. Lindholm and L.E. Averianov, New Middle Cretaceous ants (Hymenoptera, Formicidae) from the Taimyr Peninsula, Russia — commentary on the importance of fossil ant morphology for understanding ant evolution, Historical Biology, 2021, 34(2-3), 195-207.[3] L. Lindholm, The evolutionary history of termite jaws and their relationship to ants, Entomological Reviews, 2022, 62(2), 177-195.[4] L. Lindholm and T. Tarnanen, Phylogenetic and morphological insights into the Tupititlania and Anephialitus section of the Cretaceous Haidomyrmecinae (Hymenoptera, Formicidae), Journal of Paleontology, 2020, 94(4), 653-670.
- The study published in Current Biology reveals that the ancient ant species, Vulcanidris cratensis, belonged to the extinct subfamily Haidomyrmecinae, also known as 'hell ants.'
- These 'hell ants' were vicious predators during the Cretaceous period and had unique predatory adaptations, such as scythe-like jaws that moved forward, rather than sideways like modern ant mandibles.
- The fascinating discovery of Vulcanidris cratensis, dating 113 million years ago, indicates that these 'hell ants' had already spread globally, as evidenced by its fossil origin in the Crato Formation in Brazil.
- The evolution of these early ants, such as the 'hell ants,' sheds light on the development of complex adaptations among insects, demonstrating their rapid diversification and expansion across the world.
