Naetrocymbaceae Leptorhaphis epidermidis Growth type crustose Chemical results negative Only found on Birch but can be locally abundant Thallus usually absent but patches of Trentepohia occasionally occur round ascomata. Oval perithecia (0.3-0.5mm), the dark brown involucrellum appearing as a dark basal fringe. Asci 8-spored, spores curved with pointed apices, 1-septate, 25-35 x 2-3.5 µm. Microscope photograph below. Similar: Leptorhaphis atomaria occurs on deciduous trees, mainly Populus tremula (Aspen), Salix and Fraxinus. On Birch Arthopyrenia analepta looks similar but the spores are wider and 1-septate

Microscope photograph

Leptorhaphis epidermidis
On Birch. Holton Lee, Dorset. October 2012