Ultrastructural studies of Massarina ingoldiana and M-purpurascens

Ascus and ascospore appendage structures can be important characters in del ineation of genera. We have therefore examined the ascus and ascospore ultr astructure of Massarina ingoldiana and M. purpurascens, as Massarina is tho ught to be a heterogeneous genus. The ascus wall of M. ingoldiana is two la yered and comparable to M. thalassiae. Ascospores of both species comprise an electron-transparent mesosporium, an electron-dense episporium and an ex osporial mucilaginous sheath. In this respect they are similar to the ultra structure of other Massarina species, and should be maintained in Massarina .