Big cats of insect world: Scientists discover two new army ant species

Hubballi: Researchers from Karnataka and Odisha have discovered two new species of army ants in the Eastern Ghats of Andhra Pradesh.

The findings, published in the journal Asian Myrmecology, describe Aenictus chittoorensis and Aenictus lankamallensis as keystone predators that play a critical role in regulating arthropod populations and shaping forest biodiversity by consuming large quantities of invertebrates on a daily basis.

The research team comprises Dr Dharma Rajan Priyadarshan and Ramakrishnaiah Sahanashree from the Ashoka Trust for Research in Ecology and the Environment (ATREE), Bengaluru, along with Bikas Sahoo, Nikitha Muthu Kumaran, and Aniruddha Datta Roy from the National Institute of Science Education and Research (NISER), Odisha. The species were discovered in the Sri Venkateswara Wildlife Sanctuary, which forms part of the Southern Eastern Ghats.

Speaking to DH, Sahanashree explained that army ants were nomadic insects whose mass foraging raids have far-reaching ecological effects.

“Their movement through the forest floor drives out other insects, making them available as food for birds, reptiles and other predators,” she said.

“They also support specialised symbiotic arthropods and contribute to nutrient cycling within the ecosystem”.

Army ants are highly aggressive predators found mainly in tropical ecosystems.

Unlike many other ant species, they do not build permanent nests. Instead, they form temporary living structures known as ‘bivouacs’, made entirely from the bodies of worker ants. As social insects, they form massive colonies that conduct coordinated raids, consuming insects and small animals in their path.

They are distinguished by their large, sharp mandibles, stinging ability and heavy reliance on chemical pheromones to navigate and communicate. Like other army ants, the newly discovered species are completely blind and move in straight columns during raids.

“These two ant species function as top predators, similar to tigers and lions, in maintaining ecological balance and biodiversity,” said Bikas Sahoo, highlighting their importance in forest ecosystems.

“The Eastern Ghats have received far less scientific attention than Western Ghats. Our discovery of these two new army ant species shows that this landscape holds immense biodiversity and underscores the need for greater exploration and conservation efforts,” he says.

With the addition of these two species, India has now recorded 876 species of ants. Globally, scientists have identified over 14,000 ant species so far.

“The majority of ant species are found in tropical regions, and India, being a tropical country, has immense undocumented diversity,” Sahanashree said.

“Due to limited studies and extensive development activities, we may have already lost several ant species before they could be identified.”