Syn.: L. pruinifera Nyl.

On vertical surfaces of natural, calcareous outcrops in exposed conditions.

Belgium: Brab.: RRR, Mosan: AR.

Luxembourg: - .

France: - .

Lit.: Ertz: 19, L5: 28, La69: 105, NL77: 21, NL84: 15, NL97: 50.