Description: The discs (perithecia) of this crustose epiphytic lichen are reminiscent of Porina. In this species of Strigula the spores (<18µm long) are three-septate and constricted at the septa – with the two upper cells slightly larger than the lower – while the perithecia are strengthened by an involucrellum. In Ireland, it has been recorded from County Fermanagh.

Key Identification Features:

• Thallus greyish, thin, perithecia half-sunken, involucrellum present
• Spores three-septate; on the bark of old trees in woodland, sometimes spreading to the roots.

Original text submitted by Vince J. Giavarini

Distribution Map from NBN: Swinscowia jamesii at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Swinscowia jamesii at iNaturalist World Species Observations database.