Scientists have identified a new fossil honeybee species from Japan that helps fill a major gap in the evolutionary history of the genus Apis.
Named Apis aibai, the newly described species is the youngest known extinct honeybee and the oldest confirmed fossil belonging to the subgenus Apis. This group includes the Western honeybee, Apis mellifera, and its closest living relatives.
Fossil honeybees are extremely rare. Most known specimens were discovered in Oligocene and Miocene rock deposits in Europe and China and date back tens of millions of years.
Only a small number of younger honeybee fossils have been found from the Pleistocene and Holocene epochs. Those specimens belong to species that are still alive today, making Apis aibai an important addition to the fossil record.
“The honey bee, a general term for hymenopteran insects of the genus Apis (family Apidae), plays a vital role as a pollinator for both natural and agricultural ecosystems,” said Dr. Yui Takahashi of Keio Yochisha Elementary School and Dr. Jun-ichi Takahashi of Kyoto Sangyo University.
“In addition, these insects maintain some of the closest ties to human society.”
“There are at least nine living honeybee species and three subgenera — Micrapis, Megapis and Apis — within the genus Apis.”
“The native distribution of Apis mellifera extends across Europe, Africa, the Middle East, Central Asia and western China, while the other eight honeybee species are primarily distributed throughout Asia.”
“The ranges of the eight Asian species overlap in tropical and subtropical regions of South and Southeast Asia. However, only Apis cerana extends northward into the temperate zone.”
“The fossil record of Apis is concentrated in Eocene to Miocene deposits from Europe and China, with only a few exceptions dating from the Pleistocene.”
The fossil was recovered from the Teragi Group in Japan’s Hyogo Prefecture. This geological formation consists of volcanic rocks and sediments deposited in an ancient lake environment.
The holotype of Apis aibai is preserved in whitish, tuff-rich siltstone. The fossil represents a worker bee approximately 10 mm long, with its wings, hind legs and body segments sufficiently preserved for detailed comparisons with modern honeybee species.
Geological evidence places the fossil between 2.8 and 2.2 million years ago, during the Late Pliocene to Early Pleistocene.
Analysis of the fossil’s wing veins and leg structure indicates a close resemblance to Apis nigrocincta, a living honeybee species now known only from the Philippines and Indonesia.
“This suggests that the Apis nigrocincta-related extinct group, including the new species, once had a broader distribution that reached temperate Japan during the Late Pliocene to Early Pleistocene,” the researchers said.
The discovery may also provide new clues about the origin of Apis cerana, the only honeybee species native to Japan.
“An interesting hypothesis is that the Apis nigrocincta-related extinct group may represent the ancestral bees of Apis cerana, which is the only native honeybee species in Japan,” the researchers added.
The Japanese fossil honeybee also supports genetic estimates based on mitochondrial DNA. Those studies have suggested that the subgenus Apis originated during the Late Miocene epoch.
Before the discovery of Apis aibai, however, no fossil evidence had confirmed the presence of this group before the Pleistocene.
“Thus, Apis aibai helps bridge the gap between fossil evidence and genomic estimates of Apis evolution,” the scientists concluded.
The study was published online in the journal ZooKeys.
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Y. Takahashi & J-ichi Takahashi. 2025. A honey bee fossil (Hymenoptera, Apidae) from the Late Pliocene to Early Pleistocene Teragi Group, Hyogo Prefecture, Japan: Bridging a gap in Apis evolutionary history. ZooKeys 1255: 291-301; doi: 10.3897/zookeys.1255.162389
Source: www.sci.news