Crustose lichen

Description:

Crustose lichen is deeply fixed into the rock, making it immovable. Forms circular colonies, varying in color with black rims. The fungal thread of the thalluce is used to attach it to rock. The thallace is the part of the lichen made up of fungi.

Habitat:

Growing on rocks on the edge of Lac Temiscamingue, QC

Notes:

Not quite sure whether to classify this as fungi or plant as lichen is a combination of algae & fungus.