• Arthonia almquistii Vain.

There are no records for this species at present.

This species grows on the thallus of Amygdalaria pelobotryon (which grows on base-rich siliceous rocks in lake ‘splash zones’ or near streams and rivers) and is only known from County Antrim in Ireland. The small, black rounded discs produce one-septate spores with a ‘halo’-like surround.

Key characteristics

  • Lichenicolous on the thallus of Amygdalaria pelobotryon
  • Discs tiny, black; spores one-septate with transparent halo-like outer coat.

Original text submitted by Vince J. Giavarini

 Simms, M. J., (2016). Arthonia almquistii Vain.. [In] LichenIreland. Accessed on 2018-12-10.