Collection location: Howarth Park, Santa Rosa, Sonoma Co., California, USA [Click for map]
The unknown Psathyrella that tormented me last spring. Possibly P. canoceps.
Yes, sorry. P. canoceps. Darvin suggested this ID last spring and pointed me to a monograph on Psathyrella by A.H. Smith at University of Michigan. Here’s a link to all of the monographs. P. canoceps is on page 182.