Macropis steironemantis ssp. opaca Michener

Yakima River Oil-collecting Bee (Macropis steironemantis ssp. opaca)

The Yakima River Oil-collecting Bee was described in 1938, it is known only from a very small area at a place named Morgan’s Ferry at the Yakima River in Washington, USA.

This form reaches a length of about 0,9 cm; it differs from the otherwise identical nominate race by the duller surface of its legs and vertex. [1]

The nominate form of this species itself appears to be somewhat adapted to a single species of host plant, the Prairie Loosestrife (Lysimachia quadriflora Sims), formerly known under the name of Steironema longifolium (Pursh) Raf..


The Yakima River Oil-collecting Bee is found in lists of extinct insects under a somewhat wrong name, with a wrong author and with a completely wrong description date: Macropis steironema ssp. opaca Robertson 1891.



[1] Charles D. Michener: A review of the American bees of the genus Macropis (Hymen., Apoidea). Psyche: a Journal of Entomology 45: 133-135. 1938


edited: 28.04.2021