Vitelline cells (A–C, I, J) and vitelline duct (D–H) of Sanguinicola sp. 2 from ides. (A) Vitelline cell showing the various shapes of the cytoplasmic extensions, note the presence of numerous muscle fibres around this cell. Scale bar = 2 μm. (B) Intercellular junction between a vitelline cell and the thin, sarcoplasmic extension of a muscle cell. Scale bar = 1 μm. (C) Cell junction between a vitelline cell and a sarcoplasmic extension. Scale bar = 1 μm. (D) Part of the vitelline duct filled with mature vitelline cells. Scale bar = 10 μm. (E, F) Flattened, ciliated, epithelial lining of the vitelline duct showing the inter-epithelial nuclei of these cells. Scale bars = 5 μm (E) and 2 μm (F). (G) Region of the epithelial lining of the vitelline duct showing basal ciliary bodies and a short surface lamella. Scale bar = 0.5 μm. (H) Apical septate junction in the duct epithelium. Scale bar = 0.5 μm. (I) Intercellular junction between two vitelline cells. Scale bar = 0.5 μm. (J) Heterogeneous vitelline globules. Scale bar = 0.2 μm. Abbreviations: bb = basal body of cilium, c = cilium, ca = central area of vitelline globule, cj = cell junction, dl = vitelline duct lumen, el = epithelial lining of vitelline duct, g = vitelline globule; gc = globular cluster, l = lipid droplet, lm = lamella, mf = muscle fibres, n = nucleus, pe = pseudopodium-like extension, r = lucid rim of vitelline globule, se = sarcoplasmic extension, sj = septate junction, v = vesicle, vc = vitelline cell.