Baglan slag

Aloina ambigua was found to be occasional in an area of lichen-bryophyte dominated vegetation on basic slag at Baglan. The main associates were Didymodon fallax, Barbula convoluta var. convoluta, Dicranella varia & Bryum dichotomum. Among the less frequent species were Bryoerythrophyllum ferruginascens, Cladonia pocillum, Galium parisiense, plus an unfamiliar lichen, which I'd be grateful if anyone can suggest a name, or even genus?