Collection location: Foothill Regional Park, Windsor, California, USA [Click for map]
These are growing in a group under Quercus agrifolia. Identified by sight after visiting the next day and observing younger ones with veils still attached. Gills on these individuals are brown/mauve. On younger ones the gills are more clearly lavender. I’ve seen these spelled collinitus and collinitis and am not sure which is correct but have chosen the form used by Arora.