Collection location: Pollock Pines, El Dorado Co., California, USA [Click for map]
This id is somewhat tenuous because of the limited data I have and the scarcity of references. The description and photo in Roger Phillips’ Mushrooms of North America seem to be a match. These are young specimens, I believe, accounting for the smaller stature(caps were less than 1cm across) and the lack of spores that dropped overnight. They did have the right coloring and look as well as the cap margin appressing against the stem at first. Also the white hairs at the base of the stem were present.