Family: Trypetheliaceae Species: Arthopyrenia cerasi Growth type crustose Photos: On Hazel (Corylus), Dromore, Co. Cork, SW Ireland. Non-lichenised, thallus absent but bark sometimes slightly bleached. Perithecia often elliptical, strongly domed with +/- sunken ostioles. Spores 3-septate, strongly constricted at septa (especially median one), upper part broader than lower, 14.5-19.5 x 5.5-6.5 µm, apices rounded. Pycnidia with either macro or micro conidia. Micrographs below. Involucrellum brown, K+ greenish Occurs on smooth bark, usually found on Hazel Similar: Other Arthopyrenia species have 1-septate spores

Micrographs



Arthopyrenia cerasi. July 2024