FIGURES 30–36. Fig. 30 in Gomphonema frequentiformis (Metzeltin & Krammer) comb. nov. (Bacillariophyta): ecology and taxonomy of a Neotropical diatom

FIGURES 30–36. Fig. 30. Reproduction of Gomphonema angustatum var. productum Grunow in Van Heurck (1880, pl. 24, figs 52– 55). Figs 31–36. LM and SEM of Gomphonema productum (Grunow) Lange-Bertalot & E.Reichardt (= G. angustatum var. productum ('producta') from Van Heurck) Type n° 217 showing apical pore field on both apices, sinuous raphe system and partly biseriate striae formed by round small C-like areolae. Biseriate pattern is present near the axial area. Scale bars = 10 µm.