thallus
algae
apothecia
biodiversity
caceres
close up
closeup
color
colors
colour
colours
composite organism
extremadura
foliose lichen
foliose lichens
forms
fungi
lichen
lichens
macro
macro photography
monfrague
mutualistic relationship
national park
natural
nature
pattern
physcia tribacia
rock
saxicolous lichen
saxicolous lichens
spain
stone
symbiosis
symbiotic