Description of Wittmannia
The type species is W. antarctica (Czaker, 1997) hyperparasitic in Kantharella antarctica µmesozoa, Dicyemida) in Pareledone turqueti µmollusca, Cephalopoda). The microsporidium infects the para-, dia-, and uropolar cells of nematogens and, in only one specimen, was a light infection found in the axial cell and in germinal cells and in a vermiform embryo. The cephalopod was not infected. Monomorphic, monokaryotic and diplokaryotic. Meiosis unknown. Transmission unknown, possibly by polar tube extrusion into embryos. Merogony: mono- and diplokaryotic stages lying directly in host cell cytoplasm. Myelinosomes (densely packed concentric membranes around a lucent core) present in cytoplasm of meronts and sporogonic stages. Sporonts: diplokaryotic cells with thickened membranes divide to give two sporoblasts. Division spindles formed at right angles to the plane between the two nuclei. In earlier diplokaryotic stages, with electron dense patches forming an incomplete surface coat, division spindles are oriented parallel to the plane of contact between the two nuclei. Spores: 4.3-6 x 1.7-2.3 µm (fixed)., elipsoid and diplokaryotic. Polaroplast is composed of very tightly packed membranes forming a bell-shape over loosely-packed membranes and vesicles. Polar tube is isofilar with 9-11 coils in a single rank. Posterior vacuole contains floculent material and a prominent Myelinosome.