Lichens : Arthoniales : LecanographaceaeLichens

Alyxoria paraxanthodes Nyl.

Description: Recorded only from west Galway this rare species of deep shade has a thin, greenish-yellow thallus which grows in the crevices of upland, base-rich rocks. The slit-like discs (lirellae) are like a smaller version of O. mougeotii (usually <1mm long v 1.5mm) and with shorter spores with fewer divisions (four- to five-septate v five- to seven-septate). O. varia is also similar, but has even larger discs, a less demanding habitat and a markedly different thallus colour.

Key Identification Features:

  • Thallus thin, greenish-yellow; lirellae < 1mm long, four- to five-septate
  • Crevices in base-rich rock in deeply shaded situations.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Alyxoria paraxanthodes at iNaturalist World Species Observations database.

 Giavarini, Vince J., Simms, Michael J., & Davey, Simon, 2026. Alyxoria paraxanthodes. Nyl.. [In] Lichen Ireland.
https://www.habitas.org.uk/lichenireland/species.php?item=19218. Accessed on 2026-11-12.