Cells long-cylindrical, up to 12 times longer than broad, with broadly rounded poles, chloroplast ribbon-shaped, broad, parietal. Cell length (87–)120–190 μm. breadth 15–25 μm.
Ecology: plankton, metaphyton, periphyton; ponds, puddles, wetlands, Sphagnum bogs; oligo-mesotrophic, slightly acidic habitats.
Distribution: Europe: Austria, Belarus, Czech Republic, Estonia, France, Georgia, Germany, Ireland, Italy, Latvia, Netherlands, Norway, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Ukraine, United Kingdom; North America: Canada, Greenland, USA; Central America: Cuba, Guatemala, Panama; Africa: Botswana, Cameroon, Cote d’Ivoire, Mali, Morocco, Namibia, Mozambique, Nigeria, Rwanda, South Africa, Zaïre, Zambia; Asia: China, India, Indonesia, Japan, South Korea, Russian Federation, Singapore, Thailand; Oceania: Australia, New Zealand (Compère 1977, Fritsch & Rich 1924, Grönblad & Croasdale 1971, Guiry & Guiry 2023, Hancock 1973, Kossinskaja 1952, Rino 1971); South America: Argentina (Yacubson 1960, Tell 1985), Bolivia (Thérézien 1991), Brazil (Förster 1969, Bicudo & Bicudo 1969, Sophia 1991, Taniguchi et al. 1998, Soares et al. 2007, Oliveira et al. 2013, Ramos et al. 2017), Venezuela (Krieger & Bourrelly 1956).
Note: Spirotaenia condensata is the most well-known species of the genus Spirotaenia, with numerous records worldwide. Its large size, cylindrical cells outline with broadly rounded apices, and the presence of large twisted ribbons of the chloroplast make this species easily recognizable. These cells are generally linearly paired and enveloped by a sheath of mucilage. Spirotaenia sp. reported by Yacubson (1960: 65, pl. I, fig. 8) from “ Provincia de Córdoba ” (Argentina) corresponds to S. condensata.