Description: This lichen with spherical discs (perithecia) grows on damp siliceous rocks by loughs and upland rivers like the related P. guentheri var. guentheri (described elsewhere). Microscopic examination of the spores is required for certain identification. It differs in several respects from var. guentheri (i) spores are six-eight-septate, (ii) spores have from one-three longitudinal septa, and (iii) the spores are slightly broader. Western Ireland.

Key Identification Features:

• Thallus often with violaceous or purple tinge; clustered perithecia up to half immersed and large spores (six-nine-septate)
• On damp, granitic rocks: stream gorges, outcrops by lough edges; differs from the var. lucens in spores lacking longitudinal divisions.

Original text submitted by Vince J. Giavarini

Distribution Map from NBN: Porina guentheri var. lucens at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Porina guentheri var. lucens at iNaturalist World Species Observations database.