Fig. 10 in Some Ultrastructural Features of the Planktonic Freshwater Ciliate Limnostrombidium viride (Alveolata, Ciliophora, Oligotrichida) and Improved Diagnoses of Oligotrich Taxa

Fig. 10. Extrusome attachment sites (A) and immature extrusomes (B, C) of L. viride in the TEM. (A) Freeze-fracture replica showing the extrusome attachment rosettes. (B, C) Transverse and longitudinal sections; white lines mark corresponding section planes. The extrusome shows in longitudinal section an electron-dense fusiform wall and an electron-light lumen with indistinct transverse stripes. The apical portion of the extrusome is surrounded by an electron-dense structure; both are enclosed by a membrane (arrowheads). The transverse section shows the extrusome to be composed of six electron-dense trapeziums arranged around a bright lumen. 1, attachment rosette with one central and eight peripheral particles; 2, first ring; 3, second ring; ED, electron-dense structure; EX, extrusomes. Scale bars: 1 µm.