A team of scientists recently identified the first deposits of amber in South America to contain ancient insects, providing a unique window into life that existed 112 million years ago.
The discovery, detailed in a recent study published in Communications Earth & Environment, points to the past existence of a humid, resin-producing forest that once flourished on the supercontinent Gondwana.
A Time Capsule in Resin
Amber, or fossilized tree resin, is known for trapping small plants or animals and preserving them in detail. The organisms preserved in amber are known as bio-inclusions and serve as snapshots of long-vanished ecosystems. A majority of the organisms found preserved in amber come from the Northern Hemisphere. This means that researchers have known very little about life in the Southern Hemisphere during the Cretaceous period.
That changed when a team led by paleontologist Xavier Delclòs discovered amber in Ecuador’s Hollín Formation, part of the country’s Oriente Basin. The deposit was found within the Genoveva quarry in Napo Province and dates to roughly 112 million years ago.
The team identified two distinct types of amber. The first formed underground, close to the roots of resin-producing trees, and contained no visible inclusions. The second formed above ground in the open air, allowing for organisms to become trapped inside. From 60 samples of the open-air amber, the researchers found 21 that contained bio-inclusions.
Insects Frozen in Time
Among the discoveries were biting midges, long-legged flies, beetles, and caddisflies. There were also several species of wasps, including rare parasitoid families Stigmaphronidae and Scelionidae. As with many Cretaceous amber deposits, Diptera, or standard flies, were the primary species found in these bio-inclusions.
A few specimens, such as a new Microphorites fly species, closely resemble relatives found in Lebanese amber. This hints at ancient links across Gondwana and the Tethyan tropics. Even a delicate spider web, still stretched between strands, was preserved inside the amber.
Clues From the Forest Floor
Rocks found in the surrounding area also contained fossilized pollen, spores, and other fragments of plants. These fossils suggest that ferns, cycads, conifers, and other plants existed in the same time period as the bio-inclusions discovered in the amber. Together, the findings point to a humid, densely vegetated forest with freshwater pools. These conditions would have supported both resin production and the diverse insect life now preserved in the amber.
Chemical tests confirmed the amber came from Araucariaceae, a type of conifer still found in South America and Australasia. The tests also indicate that nearby petroleum seeped into the amber over millions of years. That process altered its chemistry but may also have protected it from decay, preserving this Cretaceous time capsule in near-perfect form.
A Window Into Gondwana
The Genoveva quarry represents the largest Mesozoic amber deposit discovered in South America and is among the few in the Southern Hemisphere to contain insect inclusions. Previously, most information about Cretaceous ecosystems came from amber found at sites in Myanmar, Spain, and Lebanon. The quarry provides scientists with insights into insects that existed at the western edge of Gondwana, helping to fill a major gap in the fossil record.
The discovery also challenges previous ideas about the region’s climate. Evidence from the Genoveva forest points to wet, tropical conditions, in contrast to the arid environment of Brazil’s well-known Crato Formation to the east. This difference supports climate models that predict a wetter western tropics and a drier eastern region in mid-Cretaceous South America.
Through the documentation of both insect and plant fossils found in the same deposit, the study provides new information on forest composition, resin production, and biodiversity on the supercontinent Gondwana during the Cretaceous Resinous Interval.
Austin Burgess is a writer and researcher with a background in sales, marketing, and data analytics. He holds a Master of Business Administration and a Bachelor of Science in Business Administration, along with a certification in Data Analytics. His work combines analytical training with a focus on emerging science, aerospace, and astronomical research.