FIGURE 3. A–D in Morphological diversity of benthic Nostocales (Cyanoprokaryota/Cyanobacteria) from the tropical rocky shores of Huatulco region, Oaxaca, México

FIGURE 3. A–D. Ophiothrix sp. A. Filament with wide "U" shape. B. False branching detail. C. Apex closed and intercalary heterocyte. D. Isopolar hormogonia. E. Heteropolar hormogonia. F. Hormogonia formation by necridic cell. G–L. Petalonema sp. G. Thallus showing erect loops. H, L. Filament folds with loops. I. Isopolar hormogonia formation by heterocytes. J. Closed apex. K. Trichomes constricted at cross walls. nc = necridic cell, bhet = basal heterocyte, ihet = intercalary heterocyte, phet = pro-heterocyte. Scale bars: A = 20 μm, G = 30 μm, B–F, H–L = 6 μm.