Figure 3. Photomicrographs of Gonostomum kuehnelti from life (a–g) and after protargol staining (h– k). (a) ventral view of a representative specimen; (b) ventral view of a different individual; (c) anterior body portion in ventral view showing adoral zone of membranelles; (d) dorsal view, showing the three caudal cirri; (e) loose arrangement of cortical granules on dorsal side (arrowheads) and the dorsal cilia (arrows); (f) dorsal view demonstrating single-celled ingested green algae (arrowheads); (g) resting cyst, showing the optical cross-section; (h) ventral view of the anterior portion showing the frontoventral ciliature (circled by dotted line) and buccal cirrus (arrowhead); (i) ventral view, showing transverse cirri (arrows), pretransverse ventral cirri (arrowheads) and macronuclear nodules; (j) dorsal view of anterior body portion showing the dorsal kineties (1–3); (k) posterior region of cell showing the caudal cirri (arrowheads). AZM, adoral zone of membranelles; CV, contractile vacuole; CC, caudal cirri; E, endoral; FC, frontal cirri; FT, frontoterminal cirri; FVC, frontoventral cirri; LMR, left marginal row; Ma, macronuclear nodules; P, paroral; PVC, postoral ventral cirri; RMR, right marginal row; 1–3, dorsal kineties. Scale bars: a, b, i = 40 μm; f = 7 μm; g = 20 μm.