Perhaps a species of Inocybe. A number of Inocybes are small, brown, with that little extra peak or bump at the centre of the cap and with a tendency to show some radial splitting of the cap. If I were out looking for Inocybes this is the sort of specimen I would collect - while knowing that I'd not be convinced until I'd studied it microscopically.
If the spore print were a dullish brown that would be more naked-eye evidence in favour of Inocybe. However, a look at spore shape and some microscopic gill features would be the clincher.