I believe the larger, darker ones had dark brown workers but the lighter ones had yellow workers. They are about 9mm and 7mm by my measure.
Interestingly, these are both different from a third species that flew two weeks earlier on 8/25 in the same conditions and location. That one had coloration and size midway between these two, a mid brown about 8mm. I don't have a pic handy but that was identified here as either L brevicornis or nearcticus. I definitely think I had 3 distinct species all together. They were abundant enough I don't believe they came from single colonies.
Thanks!
Edited by Polyacanthus, April 18 2022 - 8:49 PM.