Figure 2. Morphology of Cthulhu macrofasciculumque by differential interference contrast light microscopy (LM) and scanning electron microscopy (SEM).

(A) SEM showing overall characteristics of Cthulhu, including the posteriorly protruding axostyle and subanterior emergence of a bundle of flagella. Because they are bundled an exact number is hard to conclude, but 20 distinct flagella can be counted in this picture and in (B), which is a detailed view of the flagellar emergence. This flagellar bundle has an elongated shape, but others (e.g., G) appear rounded. (C & D) LM showing the overall body plan of the cell, including the pointed protruding axostyle which extends to the slightly subanterior flagellar emergence point where the single nucleus is situated (not shown), and the flagellar bundle. (E–H) Various views of the flagellar bundle and its emergence point in different cells and at different stages of the flagellar beat. It may appear as a single tight bundle projecting foraward (H), dissociated and trailing (D & E), and the emergence of the bundle may appear rounded (F & G) or band-like (E). In many views striations beneath the surface where the flagella emerge are visible (C & H). All scale bars are 10 µm except (B), which is 2 µm.