Opegraphaceae Sparria endlicheri (Arthonia endlicheri) Growth type crustose Chemical results: K-, C+ red, KC+ red, P-, UV- BLS conservation evaluation: LC NS Sc Most often found on siliceous coastal rocks under dry, shelterd overhangs. Thick, uneven, whitish-pink thallus, often forming ridges or sometimes rosette-like. Upper surface sorediate, the soredia packed with minute crystals. Apothecia very rare, spores 3-5 septate, 14-20 x 5-7 µm. Similar: Dirina massiliensis f. sorediata has a thinner thallus

Arthonia endlicheri
On chert and limestone, Portland, Dorset. February 2016