A–G Encyonopsis indonesica sp. nov. (SEM). Internal view A–C whole valve D, E central area with rounded or elongated areolae located in a transapically elongated grooves F, G valve ends with typical helictoglossa. Note a thin, plate-like silica thickening present between helictoglossa and apex. Scale bars: 2 µm (A, C), 2.5 µm (B), 1 µm (D, E), 0.5 µm (F, G).