Two new lignicolous species of Nitschkia from Argentina.

Two species of Nitschkia are described from bark and wood of a legume shrub, native to the semiarid regions of Argentina. Nitschkia campylospora is characterized by asci with a variable number of ascospores, mainly 16, and curved ascospores; hairy ascomata and large ascospores are two distinct features of Nitschkia pilosa. The new species are compared with most similar species. A key to Nitschkia species is provided with the inclusion of comments on those from Argentina and neighboring countries.