Lichen: Acrocordia gemmata
Name: Acrocordia gemmata (Ach.) A.Massal.(1854)
Pronunciation: Acrocordia gemmata
Conservation Evaluation: Least Concern
Body Type: Crustose
Description: The reproductive structures are pycnidia and perithecia. The perithecia appear as small black hemispheres (< 1mm diameter) that are immersed in the thallus to some degree. The hole at the top of a perithecium may be off centre. The thin thallus is distinctly matt in texture and varies in colour from white to grey.
Chemical Tests: All negative.
Nature Notes: Found on rough bark of mature (basic) trees such as Ash and Oak. It needs light so it tends to occur in mature parklands and wayside trees. It is also sensitive to SO2 pollution. It is rare on smooth bark and does not occur on rock. Could be confused with Anisomeridium biforme but seen side by side Acrocordia gemmata has much smaller perithecia.
Vice county distribution map: See Map
Link: Map this species on the Lichen Survey
Other species recorded in Ireland:
- Acrocordia conoidea (Fr.) Körb.
- Acrocordia gemmata (Ach.) A.Massal.
- Acrocordia macrospora A.Massal.
- Acrocordia salweyi (Leight. ex Nyl.) A.L.Sm.
Text and images © Paul Whelan, 2009.