Abstract
Pronectria raetzelii is described as new to science from a pine forest in Brandenburg, Germany. It is characterised by its immersed, pale orange perithecia, growing within the hymenium of the host’s ascomata, and by the very small ascospores, 7‒10 × 2‒3 µm, the narrowest among the known species of Pronectria and Xenonectriella. A key to the species of Hypocreales growing on Peltigera is provided.