Placopsis lambii forma.
This form is in the form of scales separated from each other or isolated but always with grayish soralia. Apothecia rare, only one per scale, orange-pink. C+ pink, KC+ red. On slate waste in drier and sunnier areas than for the type.
N.B. Very similar and with identical color chemical reactions to Trapelia involuta which can cohabit but the latter species has more convex scales and no soralia.