Nail Fungus Poronia punctata (L.) Fr. (illustrated 60% life size) Fruit body 0.5–1.5cm across, 0.5–2cm high, flattened disc, attached to the substrate by a long, black, cylindrical stalk; whitish, dotted black with tips of perithecia when mature. Spores 18–26×7–12¼, bean-shaped, smooth. Asci 180×18¼. Habitat on horse dung; autumn. Once abundant, quite rare in modern times due to the decline in the use of horses, endangered on Red Data List. Not edible.