Lichen: Pyrenula dermatodes
Name: Pyrenula dermatodes (Borrer) Schaer. (1850)
Pronunciation:Pyrenula dermatodes
Conservation Evaluation: Nationally Rare, International Responsibility
Body Type: Crustose
Description: The cracked or areolate and shiny thallus is generally a rusty red-brown colour but sometimes turns yellowish green. Apothecia and pseudocyphellae are absent. Perithecia are abundant and sunken into the thallus with just the grey tip or ostiole showing. Sometimes they emerge (or are grazed by snails/slugs) and are visible as black discs. Spores are 3-septate. It is the only Pyrenula where the perithecia are totally sunken in the thallus.
Chemical Tests: C-, K+ orange red, KC-, Pd-, UV+ yellow orange
Nature Notes: A very rare species and is hardly know outside of Ireland. Only known from two locations in Scotland. Found in old ‘oceanic’ woodlands. Locally common. Noticed as large red/orange patches on trees such as holly, beech, hawthorn and rowan. It seems particularly fond of holly.
Vice county distribution map: See map
Link: Map this species on the Lichen Survey
Other species recorded in Ireland:
- Pyrenula acutispora
- Pyrenula aff. Microtheca R.C.Harris
- Pyrenula chlorospila Arnold
- Pyrenula hibernica
- Pyrenula laevigata (Pers.) Arnold
- Pyrenula macrospora (Degel.) Coppins & P.James
- Pyrenula occidentalis (R.C.Harris) R.C.Harris
Text and images © Paul Whelan, 2009.




