Autumn Maust at work near Mount Rainier.
Bee experts wouldn't have previously expected to find the likes of Osmia cyaneonitens, Dufourea dilatipes and Stelis heronae in Washington. But this year, researchers added eight new bee species to a list of the state's native pollinators.
While collecting pollinators in Chelan County to study how climate and wildfires affect native bee populations, Autumn Maust, a UW research scientist of biology, discovered eight bee species never recorded in Washington and 100 species that had not previously been documented in Chelan County. Expert taxonomists from Utah to British Columbia helped her identify the bees, which were photographed in high resolution for her research.
"It's a really exciting moment. Sitting with an expert taxonomist to determine the identity of an undocumented bee filled me with awe," Maust said. "They cited subtle characteristics that I would not have even known to examine. The findings also have important implications for biodiversity. It's difficult to conserve a species when we don't know its name or native range."
Taxonomists refer to detailed sets of characteristics to differentiate bees by family, genera and species. The morphological qualities of bees are incredibly diverse, and individual species can vary in small but significant ways. Bees can be distinguished from each other by the shape and structure of wing veins, hair color on the 'terga' - plates forming the bee's abdomen - and the location of 'scopa,' or pollen carrying hairs.
If you are interested in bees, Maust said, the Washington Bee Atlas trains volunteers to find, collect, and identify native bees. Individuals can also share bee photos and observations on sites like iNauralist where the data is made available to researchers.
Depicted below are a few of the new-to-Washington bees Maust observed and the characteristics scientists focused on for classification. Click the image to see the full resolution photo.
The scopa on the abdomen of this female bee and its heavily pitted 'terga' with inflated edges helped Maust to identify it as Dianthidium singulare.
credit="Autumn MaustAutumn Maust
This fierce-looking female Osmia cyaneonitens has huge mandibles (teeth) and flashy blue coloring. Osmia, in the mason bee family, use their large mandibles to move mud or cut leaves or petals to build nests. Their bodies are often metallic blue and green.
credit="Joel Gardner/WSUJoel Gardner/WSU
This Dufourea dilatipes Maust collected belongs to a rare group of the Halictidae family, commonly called 'sweat bees' because they are attracted to the salt and moisture in the sweat of mammals. All members of this family have a strongly arched basal vein on the forewing. Dufourea dilatipes exclusively forages on Calochortus flowers for pollen and nectar.
credit="Josh Milnes/WSDAJosh Milnes/WSDA
Black and brown coloration on the head, abdomen and thorax is one trait of Melissodes nigracauda. This one was caught in a soap/water trap, which Maust said can result in a spiky hairdo sometimes smoothed by "relaxing" the bee and giving it a blow dry before pinning.
credit="Autumn MaustAutumn Maust
Stelis heronae, at 4 to 5 millimeters long, is so small it was hard for Maust to pin. It wasn't described by any taxonomists until 2024, which made it tricky to identify. Stelis heronae is distinguished from other species by the maculations, or colored markings, on its terga. It is a cuckoo, or parasitic, bee that lays its eggs in the nests of other bees. Maust pointed out that female Stelis lack scopal hairs under their abdomens because, like other parasitic bees, they do not gather pollen but instead rely on the pollen stores of their hosts.
credit="Autumn MaustAutumn Maust
