Cercidospora parva and Feltgeniomyces mongolicus are reported for the first time from North America, the latter is also first documented from the Arctic. Micarea inquinans is newly reported for Russia, and Epithamnolia xanthoriae is reported as new to European Russia. Baeomyces and Dibaeis are reported as new host genera for Epithamnolia xanthoriae, and Dibaeis for Merismatium nigritellum. A key to the species of lichenicolous fungi growing on Hypogymnia is provided. Keywords. – Biodiversity discovery, biogeography, floristics, lichen-dwelling fungi, United States of America.