Not much in the world has survived to be known as old as the dinosaurs, but when it comes to a recently discovered insect species, the statement holds true. Some 99 million years ago, a tiny insect belonging to a previously unknown species became trapped in tree resin. The resin hardened and turned into amber; the fossil preserved within it has now led a team of researchers from the School of Zoology and The Steinhardt Museum of Natural History to identify and describe a new species named Cretodorus noonoo, or ‘Noo-Noo’.The researchers examined insect fossils belonging to Neazoniidae, an ancient family of planthoppers, including 13 specimens preserved in Kachin amber from Myanmar. The study published in the journal Insectsalso revealed an extraordinary biological adaptation that characterised Noo-Noo and its close relatives, exceptionally long and flexible mouthparts that were twice the length of their body. The researchers believe that this unusual structure enabled the insects to reach food sources that were inaccessible to insects with more rigid mouthparts, deep inside cracks and crevices in tree bark. In their modern relatives, the mouthparts are structured like a simple needle, allowing them to pierce plant tissues and suck fluids from them.
Unique mouthparts that no longer exist
The ancient insects examined were found to possess extremely elongated mouthparts, the surface of which was densely covered with transverse folds. Using high-resolution micro-computed tomography, the researchers were able to reconstruct their internal structure. The scans showed that the folds were not merely external ornamentation but part of the structure itself. They likely gave the mouthparts flexibility while preventing them from kinking or collapsing, much like a bendy drinking straw or a corrugated flexible hose.In some of the preserved fossils, the mouthparts were preserved in a bent position. Because the amber froze the insects in place when they became trapped in the resin, the researchers view this as further evidence that the mouthparts were also flexible during the insects’ lifetimes. Such a structure is unknown among their living relatives today, pointing to an ancient evolutionary solution that has since disappeared.The mouthparts of “Noo-Noo” pointed backwards and functioned as a piercing-and-sucking system that, like the mouthparts of their modern relatives, was less suitable for feeding on nectar. Moreover, despite examining numerous fossils, the researchers found no convincing evidence of pollen accumulating on their bodies, a sign that would have indicated a role as pollinators.According to an explanation proposed by the researchers, these insects were specialists in sucking sap from trees. Their long, flexible mouthparts could have snaked through narrow cracks in the bark and guided the piercing organs toward the deep vascular tissues.At the tip was another unusual feature: a structure with two grooved lobes that likely opened during feeding, helping to anchor the mouthpart to the walls of the crack, much like a wall anchor expanding inside a drilled hole.
The forests and insects of the time
The researchers’ discovery may also have broader significance for the understanding of Cretaceous forests. Long or corrugated feeding structures appeared in several unrelated insect groups during this period, raising the possibility that forests rich in thick-barked trees provided an advantage for insects capable of reaching deeper tissues.The study notes that resin-producing forests of the Cretaceous period were also associated with evidence of recurrent fires and that trees in fire-prone environments often develop thicker bark. The researchers cautiously suggest that such conditions may have created ecological opportunities for unique feeding strategies, ones that are almost entirely absent among planthoppers today.“The discovery of ‘Noo-Noo,’ a new species that lived approximately 99 million years ago, gives us an extraordinary glimpse into the insect world of the age of the dinosaurs. This is not merely an insect previously unknown to science, but an animal that developed an evolutionary solution with almost no modern equivalent: a long, flexible and durable feeding organ that likely enabled it to reach food deep within tree bark,” said Dr. Leonidas-Romanos Davranoglou of the School of Zoology, one of the study authors.“The fact that similar structures appeared in several insect groups during the Cretaceous period suggests that ancient forests created ecological conditions and opportunities very different from those we know today. The discovery of a new species like this is therefore not simply the addition of another name to the tree of life, but another piece of the puzzle that enables us to reconstruct what ecosystems looked like and how they functioned tens of millions of years ago,” they added.