• Porina ahlesiana (Körb.) Zahlbr.
Porina ahlesiana
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This tiny crustose lichen with spherical perithecia for discs, grows on damp, sheltered siliceous rocks often close to some source of base influence (limestone or similar). It has a green-grey thallus and distinctive perithecia which are pale orange-brown above and sometimes grey at the base. It can be overlooked for the red-orange more vibrantly coloured P. lectissima which has three-septate spores compared with six- to seven-septate, narrowly ellipsoid spores in P. alhesiana. In Ireland, the species has not been seen for many years.

Key characteristics

  • Pale orange-brown perithecia containing six- to seven-septate spores
  • Damp, sheltered rocks often near rivers.

Original text submitted by Vince J. Giavarini

 Simms, M. J., (2016). Porina ahlesiana (Körb.) Zahlbr.. [In] LichenIreland. Accessed on 2018-08-17.