Myriotrema endoflavescens Hale ex Lücking  

Mycobank MB 517799

Thallus light yellow-olive, smooth to uneven, in parts bullate to almost gall-forming, with dense, prosoplectenchymatous cortex with internal splitting; medulla pale yellow; photobiont layer and/or medulla with clusters of calcium oxalate crystals. Apothecia immersed, rounded, 0.2–0.4 mm diam.; disc covered by narrow, 0.1–0.2 mm wide pore, flesh-colored, white-pruinose; margin entire, fused, light yellow. Columella absent. Excipulum prosoplectenchymatous, yellow-brown; periphysoids absent. Hymenium 60–80 µm high; paraphyses unbranched. Ascospores 8/ascus, 3–5-septate, 15–20 x 5–7 µm, ellipsoid, with thick septa and lens-shaped lumina, colourless, I+ violet-blue (amyloid). Secondary chemistry: no substances (all spot tests negative); medulla with pale yellow pigment (K+ yellow).