Thalli, transversal cross-sections: A Thallus with pseudocortex and densely interwoven hyphae (Rostania quadrifida, McCune 2744, UPS) B Thallus with pseudocortex and straight and unbranched hyphae which are perpendicular to the surface (Rostania paramensis, Palice 2796, holotype of Collema paramense) C Thallus with eucortex and straight and unbranched hyphae which are perpendicular to the surface (Leptogium azureum, Tehler 3140, S) D Thallus with eucortex and paraplectenchymateous throughout (Scytinium sp. Palice 2273) E Thallus paraplectenchymateous throughout (Rostania occultata var. populina, Llop 56060303, S) A–E in lactic blue C in water. euC = eucortex, PsC = pseudocortex, Hp = hyphae, pPlect = paraplechtenchyma. Scale bar = 10 µm