'', New Zealand '' (pixies' parasol) growing on a log in Australia ''
Mycenas are hard to identify to species and some are distinguishable only by microscopic features such as the shape of the cystidia. In terms of morphology,
Mycena mushrooms are notably minute in their size (anywhere from 0.5 to ~15 cm in cap-size). Pileate-stipitate in form, there can exist a wide range in both the anatomical characteristics and color of the
basidiocarps—though most often basidiocarps are grey or brown. creating a glow known as
foxfire. These species are divided among 16 lineages, leading to evolutionary uncertainty in whether the luminescence developed once and was lost among many species, or evolved in parallel by several species. One advantage of bioluminescence may lie in its potential to attract insects that can disperse the mushroom's spores. Bioluminescence in the genus occurs as a reaction between oxygen and
luciferin molecules catalyzed by the enzyme luciferase. In recent years, mycologists have conducted research examining the development of bioluminescence within fungi, investigating the origin of the genes coding for luciferase enzymes that cause these fantastic visible traits. So far, the literature suggests 3 separate origins of bioluminescence within Agaricales, occurring within the families
Omphalotaceae,
Physalacriaceae, and
Mycenaceae. ==Ecology==