Mycena adonis

Mycena adonis, commonly known as the scarlet bonnet, is a species of fungus in the Mycenaceae family. Found in Asia, Europe, and North America, it produces small orangish to reddish inedible mushrooms with caps up to 1.2 cm (0.5 in) in diameter, held by thin pinkish-white stems reaching 4 cm (1.6 in) long. The fungus prefers to grow in conifer woods and peat bogs, suggesting a preference for acidic environments. The appearance of several atypical fruitings of Mycena adonis on deciduous wood in the Netherlands in the late 1970s was attributed to increases in atmospheric pollution that raised the acidity of the wood substrate. Mushrooms resembling M. adonis include M. acicula, M. aurantiidisca, and M. rosella.