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When we think of pollinating insects, bees, butterflies, or flies usually come to mind—but rarely true bugs. Yet it seems that in the past, they also played an important role in plant pollination. A Hungarian research group has now confirmed, based on an ancient bug preserved in nearly 100-million-year-old Burmese amber, that this behavior may have been more widespread among bugs in earlier stages of Earth's history.

The work is in the journal Scientific Reports.

The study of amber inclusions is an important tool for uncovering the biodiversity and evolutionary patterns of past ages. Fossils of certain groups of organisms (for example, arthropods) are often poorly preserved and lack detail, surviving in good condition only when trapped in fossilized resin.

One of the most important amber deposits from the Mesozoic era is Burmese amber (also known as burmite). This amber formed during the Late Cretaceous, about 99 million years ago, on the West Burma terrane—a landmass that had already separated from the supercontinent Gondwana more than 100 million years earlier and remained in the equatorial region of the Tethys Ocean until the Late Eocene. As a result, although its wildlife originated from Gondwana, it evolved in isolation for millions of years, giving rise to a rich array of unique flora and fauna.

While studying such an inclusion, Péter Kóbor (Plant Protection Institute, HUN-REN ATK) and Márton Szabó (Department of Paleontology and Geology, Hungarian Natural History Museum, and Department of Paleontology, Eötvös Loránd University) discovered a flat bug (family Aradidae) belonging to the subfamily Prosympiestinae, which retains ancient (plesiomorphic) traits. This is the first known representative of this subfamily in Burmese amber.

The find is interesting even within the family, since all flat bugs previously known from Burmese amber belonged to more derived (apomorphic) groups, while older lineages were absent from the faunal inventory. What truly makes the newly described species, named Shaykayatcoris michalskii, remarkable, however, is its iridescent, shimmering exoskeleton—never before seen in this family.

Although iridescence is not uncommon among bugs, it is particularly unusual in such cryptic groups as flat bugs. True to their name, these insects typically live under tree bark and feed on fungal hyphae. Their lifestyle is associated with specific morphological adaptations, such as a strongly flattened body (dorsoventrally) and elongated stylets, which are coiled inside the head capsule at rest. By contrast, members of the Prosympiestinae subfamily differ both in lifestyle and morphology: Their bodies are more cylindrical, and they live mostly in leaf litter or under logs and branches lying on the ground.

Iridescence may serve two functions. It can act as a deterrent (aposematism) if the coloration is bright (e.g., red) and highly conspicuous, but this is unlikely here since the bug's base color is brownish. More probably, it functioned as camouflage, helping the insect blend into a floral environment—this explanation is more plausible.

The amber also contained plant fragments and a large amount of pollen surrounding the insect, with grains even stuck to its body. This, together with its iridescent coloration, suggests that the bug visited flowers—and likely played a role in pollination.

The discovery confirms that bugs' role in flower visitation, and possibly in pollination, may have been much more significant in earlier evolutionary stages than it is today. Most modern bugs are no longer flower visitors, likely having been displaced from this "niche" by more specialized pollinators such as bees.

This finding helps us understand how today's insect fauna evolved, and how species responded to competition and environmental changes. Armed with this knowledge, we can also better navigate current ecological and agricultural challenges—such as the decline of pollinators.