Fig. 2. SEM. Left sulcal list widens posteriorly, supported by 3 ribs. Widest width of cell between second and third sulcal rib.
Fig. 3. LM. Large food vacuoles present. FV=food vacuole. Left sulcal list ribs (3) visible.
Fig. 4. LM. Posterior nucleus. N=nucleus.
Fig. 5. LM. Thecal surface covered with poroids and scattered pores.
Fig. 6. Line drawing. Cingular lists: well developed and finely striated. Anterior cingular list does not obscure areolated epitheca. ACL=anterior cingular list; PCL=posterior cingular list.