In a paper published online in the journal Palaeodiversity, Oregon State University’s Professor George Poinar Jr. described a new family, genus and species of pollen-collecting bee found in a piece of 99-million-year-old amber (mid-Cretaceous period) excavated from a mine in Myanmar.

Bees are an important component in the evolutionary history and diversification of flowering plants (angiosperms).

The great majority of bees depend on pollen, nectar, oils, waxes, scents and resins from flowering plants for adult and larval nutrition, sexual attractants and nest construction.

Bees evolved from apoid wasps, which are carnivores. Not much is known, however, about the changes wasps underwent as they made that dietary transition.

The newly-described primitive bee is so unique that Professor Poinar decided to establish a new genus and family (Discoscapidae) for it.

Named Discoscapa apicula, the ancient insect is a small, black, mostly hairless, pollen-collecting bee.

It shares traits with modern bees — including plumose hairs, a rounded pronotal lobe, and a pair of spurs on the hind tibia — and also those of apoid wasps, such as very low-placed antennal sockets and certain wing-vein features.

“Something unique about the new family that’s not found on any extant or extinct lineage of apoid wasps or bees is a bifurcated scape,” Professor Poinar said.

“The fossil record of bees is pretty vast, but most are from the last 65 million years and look a lot like modern bees.”

“Fossils like the one in this study can tell us about the changes certain wasp lineages underwent as they became palynivores — pollen eaters.”

The single female specimen of Discoscapa apicula is positioned at the edge of a small piece of amber.

The specimen, which was obtained from a mine first excavated in 2001, in the Hukawng Valley, southwest of Maingkhwan in Kachin State in Myanmar, contains beetle parasites.

Pollen grains on its legs show that the bee had recently visited one or more flowers.

“Additional evidence that the fossil bee had visited flowers are the 21 beetle triungulins — larvae — in the same piece of amber that were hitching a ride back to the bee’s nest to dine on bee larvae and their provisions, food left by the female,” Professor Poinar said.

“It is certainly possible that the large number of triungulins caused the bee to accidentally fly into the resin.”

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George Poinar Jr. 2020. Discoscapidae fam. nov. (Hymenoptera: Apoidea), a new family of stem lineage bees with associated beetle triungulins in mid-Cretaceous Burmese amber. Palaeodiversity 12 (1): 1-9; doi: 10.18476/pale.v13.a1