Irish lichens

Cliostomum tenerum

Order: Lecanorales       Family: Ramalinaceae

Species: Cliostomum tenerum

Growth type crustose
Photos: On coastal rock, Allihies, Co. Cork, SW Ireland.
Identification needs confirming

Thallus formed of minute, +/- scattered, cream to grey-green areoles, sometimes with a visible whitish prothallus. Inconspicuous white, pale green or pink-brown apothecia, 0.1-0.2(-0.5)mm, the margins becoming excluded. Asci 8-spored, spores pointed, usually simple but can be 1-3 septate, 7-10(-15) x (1.5-)2-3 Ám. Pycnidia are frequent. Microscope photograph below.
Thallus K+ yellow, C-, P+ red

A coastal species only found in dry, shaded crevices of siliceous rocks in the 'grey zone'. Easily overlooked but can form extensive patches.

Cliostomum tenerum

Microscope photograph
Cliostomum tenerum, ascospores
Cliostomum tenerum March 2012

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