| Usnea | |
|---|---|
| |
| Usnea cavernosa | |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Lecanoromycetes |
| Order: | Lecanorales |
| Family: | Parmeliaceae |
| Genus: | Usnea Dill. ex. Adans. (1763) |
| Type species | |
| Usnea florida | |
| Species | |
|
See text | |
| Synonyms[1] | |
Usnea is a genus of mostly pale grayish-green fruticose lichens that grow like leafless mini-shrubs or tassels anchored on bark or twigs.[2]: 203 The genus is in the family Parmeliaceae. It grows all over the world. Members of the genus are commonly called old man's beard, beard lichen, or beard moss.[2]: 203
Members of the genus are similar to those of the genus Alectoria.[2]: 148 A distinguishing test is that the branches of Usnea are somewhat elastic, but the branches of Alectoria snap cleanly off.[2]: 148
- ^ Species Fungorum.
- ^ a b c d Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, ISBN 978-0-300-19500-2