Description: Porina hibernica grows on old oak bark in ancient afforested or former parkland areas and is distinguished by its bright, orange-brown (greener in shade) crust of richly branched, coral-like isidia. The spherical discs (perithecia) containing the 12- to 16-septate spores can be up to three-quarters immersed in the bark, so need to be dug out with a razor blade and squashed. The species is usually easy to identify when sterile. The structured isidia of this species is quite different from soft-textured, filamentous bark algae such as Trentepohlia. West and south-west Ireland.

Key Identification Features:

• Exclusive to ancient oak tree bark; thallus of orange-brown cylindrical isidia; black, partly sunken perithecia may be present
• The related Porina coralloidea has a similar thallus structure but it is always a dull, blackish grey; Porina rosei has similar coloured isidia but these are aggregated into mound-like clusters.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Porina hibernica at iNaturalist World Species Observations database.