Parmotrema subrigidum

Spore Ascus

Thin Section

Thallus

Lichen Index

Parmotrema rigidum thallus.

Serrate and ciliate margins, and the wrinkled nature of its lower surface are enough to identify this member of the group. As with all of our Parmotremas, it is found mostly in full sun, a harsh habitat indeed for this part of the continent. Perhaps for this reason the surface (cortex) of this lichen is thick and leathery in order to protect the algal component which would not be able to survive on its own under such conditions.