Notes: Found under live oak.
Adding some micro-details…
The first and second micro-shots are of the gill edge at 400x in Meltzer’s. The cheilocystidia are slightly mixed, with some inflated and rounded on the ends, some cylidrical, some inflated at the base, to thickened in the middle. Also no pleurocystidia are obs.
The third micro-shot is of the spores from the gill at 1000x in Meltzer’s. The spores are ellipsoid, pointed, with roughened perispore that doesn’t loosen, and they are non-dextrinoid. The apr. ave. size is 11 × 6.5 um.
Ok, from here this gets a little subtle, and takes detailed reading of “The Genus Hebeloma” by Jan Vesterholt. But he makes a big deal about the inflated middles and bases of cheilocystidia, that is an important feature of a few species. This one has a mixture of inflated and non-inflated cystidia, and that mixture is important for a few species. Then we get to the non-dextinoid spores, and this points to Hebeloma hiemale. Along with that, the growth under oaks, and the qualities of the stipe all agree, so this seems to be a pretty good id, with the descriptions in that book.