Mycetinis alliaceus has a convex cap, similar to the button mushroom, and is edible.
cap is convex edibility: edible Many well-known species have a convex pileus, including the button mushroom, various Amanita species and boletes. The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp (fungal fruiting body) that supports a spore-bearing surface, the hymenium. 
