Species: Collema fragile
Photos: Immediately below on limestone, Black Head, the Burren.
Other photographs: Muckross Abbey, Co. Kerry, Ireland
Forms small, closely attached rosettes (to 2cm) with short, +/- radiating, olive-black lobes. Thallus often partly fragmentary. Lobe ends splayed, tips of young lobes finely pubescent. Few or numerous globose isidia, apothecia very rare.
On lightly shaded, often vertical, hard calcareous rocks. Can be locally abundant in parts of the Burren, Co. Clare, rare elsewhere in Ireland. Chemical reactions negative.
Collema fragile. April 2009 and January 2010