TAXONOMIC STUDIES OF MARINE ASCOMYCOTINA - ULTRASTRUCTURE OF THE ASCI, ASCOSPORES, AND APPENDAGES OF SAVORYELLA SPECIES

The asci, ascospores, and appendages of Savoryella longispora, Savorye lla paucispora, and Savoryella appendiculata were examined at the tran smission electron microscope level. Asci of S. longispora and S. appen diculata have a well-developed apical apparatus that consists of a thi ckened electron-dense ring with a central pore. In S. appendiculata th e pore is occluded by a plug of electron-lucent material. The ascus wa ll comprises an outer narrow electron-opaque layer and an inner electr on-lucent layer that are continuous over the apical apparatus. Ascospo re walls possess an inner electron-lucent mesosporium and an outer ele ctron-opaque episporium. The episporium of the central cells of all th ree species is covered with a layer of fibrillar mucilage. Granular st rand-like outgrowths of the ascospore wall are present on the polar ce lls of S. appendiculata and S. paucispora. In all three species the hy aline polar cells of the ascospore contain organelles and in S. append iculata the polar cells are verrucose. Ascospore appendages are only f ound in S. appendiculata and these arise endogenously by outgrowth of the endosporium of the polar cell. The differences between the three s pecies are not considered significant at the generic level and therefo re all are assigned to the genus Savoryella.