Mycorrhaphium adustum (Schwein.) Maas Geest.
Saprotroph on eastern NA hardwood sticks and small logs. Tough white cap with concentrically textured rings with dark margin on edge of kidney to circular cap. Spore bearing surface on underside has a hydroid or toothed structure. Turns darker as fruitbody ages. Spore print white. Found summer and autumn in east. This is in the Steccherinaceae family of the Polyporales order.
Mycorrhaphium adustum