Foliicolous fungi were collected on living plants of mycologically rarely explored plant families in the montane Quercus-Chusquea forest of western Panama. Five new species of the genera Periconiella, Pseudocercospora, Sporidesmium, and Zasmidium are morphologically described from living leaves of Myrsine coriacea (Primulaceae) and Clusia stenophylla (Clusiaceae). A species of Bomarea (B. caldasii, Alstroemeriaceae) is recorded as host for a cercosporoid fungus (Cercospora apii s.lat.) for the first time.