Dolichousnea longissima

Methuselah's Beard Lichen
Scientific classification
Kingdom:	Fungi
Phylum:	Ascomycota
Class:	Lecanoromycetes
Order:	Lecanorales
Family:	Parmeliaceae
Genus:	Dolichousnea
Species:	D. longissima
Binomial name
Dolichousnea longissima (Ach.) Articus

Dolichousnea longissima, Old Man's Beard or Methuselah's Beard Lichen, is a lichen in the family Parmeliaceae. It was previously known as Usnea longissima.

D. longissima is found in boreal forests and coastal woodland in Europe, Asia, and North America.

This lichen is fruticose, with very long stems and short, even side branches. It is considered the longest lichen in the world. The stems are usually 15 to 30 cm in length but are sometimes much longer.

The most frequent host of this lichen is spruce trees. It is currently on threatened status.

Threatened Status

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Wikipedia