Bolbitius vitellinus Mushroom

This widespread and common mushroom is quite variable in its size and stature. Young specimens have a distinctive, yellow, egg-shaped cap--but the short-lived Bolbitius vitellinus soon begins to fade, becoming convex or broadly conical, and eventually more or less flat. Robust specimens are found on dung and in heavily fertilized soil, while flimsy specimens can be found in grassy areas with less nitrogen.
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