Growing at the base of a huge old cottonwood tree. There were four specimens total. Took tight closeup of one and noticed what appears to be Spinellus fusiger on the cap. The decorations on the cap resemble Strobilomyces spp. but the specimen under discussion here has dark brown gills, not pores like Strobilomyces. Most records for this species are outside the US; the tentative identification was made by a woman who grew up in Germany. I was unable to get a spore print. I will look for these mushrooms again in 2014 and hope to collect a specimen to send in for vouchering.