Lettauia

Cryptodiscus is a genus of fungi in the family Stictidaceae. These tiny fungi primarily decompose weathered wood, producing minute, cup-shaped fruiting bodies that remain mostly embedded within their substrate and open through small pores. Most species are wood-decaying saprotrophs found on bark-free branches and logs; one species forms thin, lichen-like crusts on soil and dead moss. The genus is distributed worldwide in boreal and temperate regions. ...read more on Wikipedia.