I have been seeing these mushroom for a few months,late Sept to mid Dec. Growing in area of a lot of oaks,on ground not on the tree. It was hard to find a mature one,seem the squirrels really like them. Gilled and attached, no ring,no hair on top of cap, white spore print,slippery top of cap when wet. Light brown or tan center of cap.They do not die off when frozen.Stem tough fiber,cap white,no staining. Growing in cluster on no more then maybe 8 or so, some all by them self.Most intact one I found under leaf litter.
Forgot to add,no odor,mild taste