Athallia cerinella is a species of bark-dwelling lichen with a thin, pale grey thallus and small, crowded, pale yellow to orange apothecia (fruiting bodies) typically less than 0.4mm across. The species grows mainly on the bark of deciduous trees such as ash, elder, and poplar, often on twigs and small branches in nutrient-enriched habitats. In the field it is virtually indistinguishable from the similar Athallia cerinelloides, but differs microscopically in having 12–16 ascospores per ascus rather than eight.

All year.

Widespread.

Unknown.