Scientists Discover New ‘Exploding Ant’ Species, First One In 80 Years

The suicidal ant rips itself apart to shoot out a "yellow goo" used to kill intruders and keep predators at a distance.

Formica rufa soldier ant ready to shoot with acid.
Andrey Pavlov / Shutterstock

The suicidal ant rips itself apart to shoot out a "yellow goo" used to kill intruders and keep predators at a distance.

“Exploding ants” have been around for quite some time and are notorious for one unique behavior (the clue is in the name). These ants have gained a fearsome reputation on the “battle ground” and are known as the kamikaze of the insect world.

This intriguing group of ants, dubbed Colobopsis cylindrica (COCY), were first discovered in 1916, the last recorded new species being identified in 1935.

Now, for the first time in 80 years, researchers have stumbled on yet another new species of “exploding ants” in Borneo, deep in the rainforest of Brunei, CBC reports.

The reason why it took eight decades for researchers to find them is that these ants live high up in the treetops, concealed within the inaccessible canopy that makes it difficult to uncover their whereabouts.

The newest member of the COCY group is described in a study that just came out in the journal ZooKeys. The scientists that discovered this newfound species of “exploding ant” named it Colobopsis explodens and detailed its peculiar behavior in the face of danger.

When faced with threats from predators or during territorial disputes, these brave little soldiers go full-on hero and protect the colony by giving up their own lives, document the study authors.

At first, the tiny ant soldiers lift up their rumps to warn predators or intruders (scientists eager to study them included, the team notes).

When this isn’t enough, the ants begin to chomp down on themselves and flex their abdomen so hard that it literally explodes, squirting out a toxic chemical.

This substance — a bright yellow, sticky goo that smells like curry, notes National Geographic — is their main defense mechanism, used to “kill or repel rivals,” the authors show in their paper.

“They explode when attacked by an enemy (or poked with a finger),” said lead researcher Alice Laciny, an entomologist with Natural History Museum Vienna in Austria.

“The composition of the goo is currently under investigation, but it certainly contains sticky and toxic components,” Laciny added.

Apart from their chemical weapon, unleashed at the cost of their lives, these small, brownish-red ants have no other means of protection. They cannot sting and lack the large mandibles other ant species rely on to fight off predators or contenders.

Their “detonating derrieres” is all that stands between them an imminent threat to the colony, notes National Geographic.

However, if all else fails, the species has one last ace up its sleeve.

What makes C. explodens completely unusual is labor division within the colony. Unlike most ant species, it is the little workers (minor ants) that take on the warrior role and are endowed with defensive chemicals.

When their self-sacrifice is not enough to get rid of danger, the colony turns to its last resort: the larger ants (or majors) tucked away inside the ant fortress.

The C. explodens major ants have modified heads with enlarged, gaping mouths, which they use to barricade the nests.

“Majors are rarely seen in the wild, as they usually remain inside the nest,” points out Laciny.

These ants have earned the moniker of “doorkeepers” because they essentially hold the door to protect the colony and keep the threat from reaching their fellow ants (cue heartbreaking flashbacks of Hodor).