Ranunculus auricomus

Ranunculus auricomus L. (the Goldilocks Buttercup): New to North America

by Carolyn L. Parker, Oct 1998

The Nulato Hills uplands in western Alaska were unknown botanically when Museum Herbarium staff were contracted by the Bureau of Land Management-Anchorage District Office to conduct a floristic survey of this large remote area two years ago. In July 1998, during our second season, we collected a buttercup none of us recognized as part of our known Alaskan flora. Researching our Herbarium library and plant collections, we determined this new plant as Ranunculus auricomus, the goldilocks buttercup. A delightful bright yellow flower, it belongs to a large species complex that is known throughout northern Russia and Europe where it forms numerous geographic races or microspecies. Our new specimen from the Nulato Hills is identical to those Russian botanists refer to as Ranunculus monophyllus which is known from Chukotka, directly across the Bering Sea from western Alaska. Our new collection was the first known record for all of North America.

The goldilocks buttercup has a close relative, Ranunculus pedatifidus ssp. affinis, the birdfoot buttercup, which is known throughout northern Alaska. We realized that if basal leaves were missing from collected specimens, these two taxa would appear very similar. I decided to look very carefully at all our herbarium specimens of R. pedatifidus ssp. affinis to see if the goldilocks buttercup, R. auricomus, had been collected previously, but misidentified and overlooked as part of our flora. It had! One collection from Serpentine Hot Springs in northern Seward Peninsula had been in our herbarium since 1987. Three additional collections were from Bluff, a seabird colony 50 miles east of Nome.

The specimens with intact basal leaves that we collected during the Nulato Hills survey alerted us that the goldilocks buttercup was indeed a part of our Alaskan flora. The permanent herbarium collections, originally misidentified, had been preserved, and now document two additional localities and habitats for this species. This is critical information. R. auricomus will be listed by the Alaska Natural Heritage Program as one of Alaska's rare plants, and because of our permanent collection data, we know more about its distribution and habitat preferences within Alaska beyond our recent Nulato Hills discovery.