Marasmius capillaris 

Marasmius capillaris02170

Marasmius capillaris Morgan 

has a pale beige to grayish-tan dry pleated cap with a depressed white center and long thin blackish stem. Fruits gregariously on oak and other leaves in hardwood forests in spring and autumn in response to rain. It shrivels up when it is dry, but reconstitutes with wet weather. Saprotrophic.  It is in the Marasmiaceae family of the Agaricales order.

Marasmius capillaris1965

Marasmius capillaris