15. Spirogyra Link

(Fig. 5A–G)

Zygospore ellipsoid to oblong, hyaline, cell wall with a coarse and irregular reticulum. Some with a well-developed fine membrane covering the entire zygospore. Long axis ca. 83–161 µm (x 156 µm), short axis ca. 35–90 µm (x 85 µm). Ecological data: Spirogyra has a cosmopolitan distribution in freshwater (Bicudo & Menezes, 2006), growing at temperatures above 20 ºC (Van Geel & Van der Hammen, 1978; Dias, 1983).