Hey all, 

So I just finished up teaching a bryophyte class with Bruce and Martin's new keys to common mosses of OR and WA. What an awesome resource! I'm sooo glad to have it for teaching bryology so thanks Bruce and Martin!

I wasn't aware of Sanionia in our bioregion until I started using the new key. I assumed everything that looked like this was Hypnum subimponens. I understand they are hard to tell apart in the field and that looking at the costa can help to differentiate (short double or strong single). My students have been keeping an iNaturalist project with all of our bryophyte observations and with field photos alone, I'm not really sure I can confidently tell the difference between these two taxa in the field. I'm wondering if any can give me some field tips. Like is Sanionia larger than Hypnum? Do they have differing habitat preferences? Here's one of my students iNaturalist posts that I'm not sure of as an example: https://www.inaturalist.org/observations/78756059 

Interestlngly, I see no iNaturalist observations of Sanionia in OR or WA. I did find couple in BC and others in Europe. 

Thanks for your help!