ASCI OF CHORIOACTIS-GEASTER (ASCOMYCETES, PEZIZALES, SARCOSCYPHACEAE), THEIR DEHISCENCE AND THEIR ASCOSPORES - ULTRASTRUCTURAL ANALYSIS

Asci in Chorioactis geaster (Peck) Kupfer ex Eckbl. differ from asci i n the Urnula (or Sarcosoma) type by the ultrastructure of their latera l wall (with a thick d layer) and apex. In some characters the apex re sembles the Sarcoscypha type. But ascus dehiscence in Chorioactis geas ter shows special characteristics (specially the dissappearance of the d 1 layer differentiations in and around the operculum) and so it dif fers from the ascus of Sarcoscypha. Consequently the disposition of th e genus Chorioactis in a separate group in the Sarcoscyphaceae is prop osed. The diversity of ascus dehiscence in this family and its biologi cal interest are emphasized.