Hymeneliaceae Hymenelia epulotica Growth type crustose. BLS conservation evaluation: LC NS Chemistry negative. Photobiont Trentepohlia, thallus scratches orange Found on damp calcareous rocks and often on limestone rock fragments or scree. Occasional on siliceous rocks flushed by base-rich water Thallus yellowish or pink-grey when fresh, endolithic or cracked areolate and orange when scratched. Apothecia with thick margins, pinkish-brown when wet, spores simple, 13-22 x 5-12 µm. Micrograph below showing the Trentepohlia photobiont Similar: Hymenelia prevostii. Visually identical but photobiont Trebouxia

Microscope photograph

Hymenelia epulotica
On limestone. Portland, Dorset. March 2016