I found just a few apothecia on soil of what I think is a Rinodina sp.. (RD 110915). There isn't much material to go on, but it appears that the apos aren't pruinose, and are somewhat convex. The spore size is a bit ambiguous, I don't have confidence that the measuring tool was working properly, but according to the measurements they are greater than 30. Spores are 2 celled. It is from a cold microsite in the sage-steppe western Montana. Input greatly appreciated!

Thanks Steve! I was thinking that R. terrestris was the best fit, but I wasn't sure about whether the spores were obviously mucronate, having never seen that before. I thought I saw a hyaline edge to some of the spores. The habitat seems right, noted on steppe. The only other species in "Biotic Soil Crust Lichens..." that has spores superficially similar is R. roscida, but being pruinose and "rare on alpine sod" doesn't fit.

Thanks Daphne, I appreciate your feedback! I am realizing that the measuring tool on the camera is not reliable, unfortunately. Cheers!