Parasola leiocephalus (P.D. Orton) Redhead, Vilgalys & Hopple
This is one of the smallest coprinoid 'inky cap’s’. Unlike Coprinus comatus or Coprinopsis atramentaria, none of the Parasola species actually deliquesce. Appears in grass after rain and collapses or disappears within a few hours. There are numerous lookalikes. Grooved cap. Free white gills that become black. Smooth hollow white stem. No partial veil. It is in the Psathyrellaceae family of the Agaricales order.
Parasola plicatilis (Coprinus plicatilis)