A single fungi with a dark green centre becoming yellow/lime green to the edge. Cap umbrella shaped, smooth and firm approx. 6 cms across. Widely spaced, deep gills, possibly white or pale orange. Stalk was 1 cm wide, 3 cms high and curvy. Tan in colour at the base turning white near the cap. No ring was present. stalk and cap quite firm to the touch. I'm taking a guess at the species.