Irish lichens

Thelotrema lepadinum
Order: Ostropales       Family: Thelotremataceae

Species: Thelotrema lepadinum

Growth type crustose.
Photos: On Holly. Ballingeary and Gougane Barra, Cork, Ireland.

Variable, the shiny greyish-cream thallus is thick or thin, smooth or uneven. Numerous barnacle-like raised apothecia in warts with large central opening. Discs are usually visible, +/- white-pruinose. In moist, shady sites apothecia are larger, more open and ulcerose. Microscope photographs below.
Host to the lichenicolous fungus Skyttea nitschkei.

Found throughout Ireland, usually on sheltered smooth-barked trees, occasionally on acidic rocks. Chemical reactions negative.

In oceanic sites could be confused with Thelotrema petractoides.


Thelotrema lepadinum


Thelotrema lepadinum


Thelotrema lepadinum


Thelotrema lepadinum

Microscope photographs
Thelotrema lepadinum, section


Thelotrema lepadinum, ascus and spores


Thelotrema lepadinum, ascospore


Thelotrema lepadinum, paraphyses
Thelotrema lepadinum. December 2008 and August 2009

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