An umbilicate lichen is a
lichen
A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualism (biology), m ...
that is only attached to its substrate at a single point.
[Lichen Vocabulary, LICHENS OF NORTH AMERICA, Sylvia and Stephen Sharnoff]
/ref> An example is '' Lasallia papulosa''.
References
Lichenology
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