English: Heath Navel on Sphagnum moss [At the time of writing, the scientific name of the lichen species that is shown here is Lichenomphalia umbellifera. It is sometimes listed as Omphalina ericetorum; for other synonyms see: http://data.nbn.org.uk/speciesInfo/taxonomy.jsp?spKey=NHMSYS0001488367 ]

This may not look like a lichen species, but appearances can be deceptive. After the initial find, I had to carefully re-examine these mushrooms in order to confirm the species identification. The mushrooms are the fungal component of the lichen, and they turned out not to be rooted in the soil, but on the stems of the Sphagnum instead; at these points, small dark green algal granules were present (these granules are the algal component of the lichen).

[Technical note: This is one of only about 50 lichen species (in the world) that are classified, on account of the kind of fungus involved, as basidiolichens. By contrast, there are over 1800 lichen species in the UK alone, and perhaps ten times as many species worldwide; almost all of them are classified as ascolichens. There are also a few deuterolichens, numbering only about 200 species worldwide. See "Lichen Biology" (edited by Thomas H. Nash III; CUP, 1997).]