lichen
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.circumpolar distribution, occurring throughout the Arctic, boreal, and temperate regions of the
Northern Hemisphere
The Northern Hemisphere is the half of Earth that is north of the Equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the solar system as Earth's Nort ...
.Matthews, Robin F. 1993 ''Peltigera aphthosa''. In: Fire Effects Information System, nline U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory.
This lichen has a large thallus that may exceed one meter in width. It is divided into lobes up to about 10 centimeters long and 6 wide. It is green, becoming pale as it dries. The thallus is dotted with
cephalodia {{Short description, Morphological structure found in some lichens
Cephalodia (singular cephalodium) are small gall-like structures found in some species of lichens that contain cyanobacterial symbionts
Symbiosis (from Greek , , "living toget ...
, which contains one of the two
symbionts
Symbiosis (from Greek , , "living together", from , , "together", and , bíōsis, "living") is any type of a close and long-term biological interaction between two different biological organisms, be it mutualistic, commensalistic, or parasit ...
, a species of ''
Nostoc
''Nostoc'', also known as star jelly, troll’s butter, spit of moon, fallen star, witch's butter (not to be confused with the fungi commonly known as witches' butter), and witch’s jelly, is the most common genus of cyanobacteria found in vari ...
''. The other is a species of ''
Coccomyxa
''Coccomyxa'' is a genus of green algae
The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/Streptophyta. The land plants (Embryophytes) h ...
''. These perform photosynthesis, and the ''Nostoc'' also fixes nitrogen. The lichen produces large apothecia, a reproductive structure.
This widespread lichen grows in a variety of habitat types, including Arcticecosystems. It grows in alpine climates in the southern parts of its distribution.
This lichen was noted to absorb aluminum and silicon from the ash released from the
1980 eruption of Mount St. Helens
On March 27, 1980, a series of volcanic explosions and pyroclastic flows began at Mount St. Helens in Skamania County, Washington, United States. A series of phreatic blasts occurred from the summit and escalated until a major explosive eru ...
Lichenopeltella santessonii
''Lichenopeltella santessonii'' is a species of lichenicolous fungus belonging to the class Dothideomycetes. It was first formally described as a new species of '' Micropeltopsis'' in 1990 by mycologists Paul Kirk and Brian Spooner. The specif ...