FIGURES 15–20: Navicula gogorevii Chudaev, Glushchenko, Kulikovskiy & Kociolek, sp. nov. SEM. External view. Figs 15, 16: Whole valve. Figs 17, 18: Central area. White arrows show the asymmetrical central pores. Fig. 17. White arrowhead shows the pointed groove ending. Figs 19, 20: Valve ends. Fig. 19. Black arrows show the distinct longitudinal grooves, separated by longitudinal siliceous strips, curved around central area and straight on the rest of the valve. White arrow shows the sickle-shaped terminal fissure, lying mostly on the valve face. Black arrowheads show the pinhole-like openings of apical areolae. Fig. 20. Black arrow shows the separate areolae, located in slit. White arrow shows the sickle-shaped terminal fissure, lying mostly on the valve face. Black arrowhead shows the pinhole-like openings of apical areolae. White arrowhead shows the pointed groove ending. Scale bars = 10 μm (Figs 15, 16); 2 μm (Figs 17, 18); 1 μm (Figs 19, 20).

Published as part of Kulikovskiy, Maxim, Chudaev, Dmitry, Glushchenko, Anton, Kuznetsova, Irina, Krivova, Zinaida & Kociolek, John Patrick, 2020, Navicula gogorevii-a new, large-celled diatom species from Vietnam (Southeast Asia), pp. 60-66 in Phytotaxa 428 (1) on page 63, DOI: 10.11646/phytotaxa.428.1.6, http://zenodo.org/record/13875905