A rare 99-million-year-old fossil that shows an enigmatic haidomyrmecine “hell ant” clamping down on its cockroach-like prey.

“Since the first hell ant was unearthed about a hundred years ago, it’s been a mystery as to why these extinct animals are so distinct from the ants we have today,” says NIJT’s Phillip Barden, lead author of the study. “This fossil reveals the mechanism behind what we might call an ‘evolutionary experiment,’ and although we see numerous such experiments in the fossil record, we often don’t have a clear picture of the evolutionary pathway that led to them.”

The reason Barden and the team see this as an “evolutionary experiment,” is because of how this feeding mechanism differs from that seen in the ants of today, which feature mouth parts that move together laterally. Conversely, the hell ant, which is thought to have vanished around 65 million years ago, moves its mandibles in a vertical fashion.

These findings help fill in some of the blanks around the feeding habits of some of the early ant species (of which hell ants are one), and how this species sustained itself across a 20-million-year existence. The team now hopes to build on this work by investigating what causes some species to become extinct while other survive and thrive.

https://newatlas.com/biology/ancient-fossil-killer-hell-ant-prey/

PermeateFree said:

A rare 99-million-year-old fossil that shows an enigmatic haidomyrmecine “hell ant” clamping down on its cockroach-like prey.

“Since the first hell ant was unearthed about a hundred years ago, it’s been a mystery as to why these extinct animals are so distinct from the ants we have today,” says NIJT’s Phillip Barden, lead author of the study. “This fossil reveals the mechanism behind what we might call an ‘evolutionary experiment,’ and although we see numerous such experiments in the fossil record, we often don’t have a clear picture of the evolutionary pathway that led to them.”

The reason Barden and the team see this as an “evolutionary experiment,” is because of how this feeding mechanism differs from that seen in the ants of today, which feature mouth parts that move together laterally. Conversely, the hell ant, which is thought to have vanished around 65 million years ago, moves its mandibles in a vertical fashion.

These findings help fill in some of the blanks around the feeding habits of some of the early ant species (of which hell ants are one), and how this species sustained itself across a 20-million-year existence. The team now hopes to build on this work by investigating what causes some species to become extinct while other survive and thrive.

https://newatlas.com/biology/ancient-fossil-killer-hell-ant-prey/

The particular hell ant locked inside this fossilized amber is Ceratomyrmex ellenbergeri and its prey, which has its head smashed between the ant’s jaws, is a cockroach-relative called Caputoraptor elegans.

“Once the prey was gripped in this way, the ant most probably moved on to an immobilizing sting—we know that the stings of hell ants were well developed,” Barden tells Hannah Osborne of Newsweek.

Speaking with Mindy Weisberger of Live Science, Barden hypothesizes the gruesome fate that may have awaited the cockroach nymph after being paralyzed by the ant’s sting: “They have these highly specialized mouthparts that are so exaggerated they can’t feed themselves. Instead, they feed the prey to their own larvae—and the larvae have unspecialized mouthparts, so they can chew normally.”

After the pale larvae have had their fill, Barden suggests the adult hell ants might make small incisions in the larvae’s’ soft bodies and drink the next generation’s blood (called hemolymph in insects). “Basically, they use their own siblings and offspring as a social digestive system,” Barden tells Live Science. “We don’t have direct evidence that’s the case here, but that could be something that’s going on.”

https://www.smithsonianmag.com/smart-news/amber-fossil-shows-hell-ant-was-unlike-anything-alive-today-180975522/?

What a great fossil

dv said:

What a great fossil

Agree. They’re handling ancient amber better these days, a hundred years ago these would have been thrown away as worthless.

“Alienopteridae is an extinct family of dictyopterans, known from the Mid-Cretaceous to Eocene. It was originally assigned to its own order Alienoptera in 2016. It was subsequently reassigned to cockroach superfamily”

The Caputoraptor elegans looks distinctly different from modern day cockroaches because of its big head. It’s a type of Alienopteridae. Alienopteridae larvae look even less like modern cockroaches. The following Alienopteridae cockroach larva could almost be mistaken for an ant.