Paleontologists in New Zealand discovered a 14.6-million-year-old bee fossil named Leioproctus barrydonovani, marking the oldest bee specimen ever recovered and the first of its kind found in the largely submerged continent of Zealandia. Discovered in the Hindon Maar Complex on New Zealand's South Island near the town of Outram, the fossil provides invaluable insights into ancient ecosystems and sheds new light on the evolution of insects in the region.
The fossilized bee, measuring just 6.4 millimeters in length, is almost perfectly preserved in volcanic mudstone. It offers researchers a rare glimpse into the past with an almost complete bee in dorsal view. The specimen reveals details such as wing vein patterns that closely resemble those of three modern Leioproctus subgenera found in New Zealand today, suggesting a possible connection to modern species.
"In fact, there are currently no data to indicate that the three groups of Leioproctus in New Zealand form a monophyletic group, and they themselves could represent multiple, younger invasions of the islands," noted the authors of the research. This suggests that today's species may not be direct descendants of the fossilized bee found in Hindon Maar.
Despite the long presence of the genus Leioproctus in New Zealand, there are only 18 endemic species of this genus—a number surprisingly low given the time span since the fossil's age. Researchers believe this indicates that either diversification was weakened by extinction caused by unknown factors, or complex biotic processes prevented the lineage from more extensive speciation.
The discovery opens new perspectives in telling the history of insects in New Zealand and raises questions about the lineage, survival, and broader history of pollinators. One possibility is that multiple waves of Leioproctus bees colonized New Zealand independently. If the current species are not related to the fossil, it would suggest a late reintroduction, likely in the Middle Miocene or the Pleistocene.
Paleontologists believe that Leioproctus barrydonovani inhabited broadleaf forests surrounding a Miocene maar lake—a crater formed by a volcanic explosion, according to dailygalaxy.com. The discovery site is renowned for its exceptionally preserved insect fossils, raising hopes of finding pollen and other bee specimens in the same Hindon Maar deposit.
"Although there is no direct evidence of the host plants of Leioproctus barrydonovani, the abundance of flowers of the genus Pseudopanax in the same deposit could indicate that this species of bee from the Miocene visited species of Pseudopanax, probably among other plants," state the authors of the study.
"This raises a compelling question: what prevented these bees from thriving and evolving into a more diverse array of species?" the researchers ask. New Zealand's insect biodiversity often presents unusual patterns. While some insect lineages have flourished in isolation, others have remained unexpectedly limited.
This article was written in collaboration with generative AI company Alchemiq