taxonID	type	description	language	source
C7390B66FFF89136AE1FF9FD0A5EFC12.taxon	description	(Fig. 2 A)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF89136AE1FF9FD0A5EFC12.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Grönblad (1945); Thomasson (1971); Melo et al. (2005); Souza de et al. (2007); Araújo et al. (2020). As B. brebissonii: Förster (1969); Uherkovich & Rai (1979); Uherkovich (1981); Souza de & Melo (2010); Cadima (2013); Feitosa et al. (2015). Western Amazonia (lowlands): Krieger & Scott (1957); Díaz-Olarte & Duque (2009); and Araujo (2003) as B. brebissonii.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF89136AE1FF9FD0A5EFC12.taxon	description	DESCRIPTION Cells 26.8 - 27.2 µm long, 15.9 - 17.0 µm wide, isthmus 16.0 µm, apex 12.1 - 12.8 µm, cells 1.6 times longer than wide. Hyaline cell wall. Semicells are barrel shaped with parallel lateral margins and truncated apex; shallow median sinus, open median constriction, and minimal basal inflation on either side of the isthmus.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF89136AC62FBBB0A9DF9B1.taxon	description	(Fig. 2 B)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF89136AC62FBBB0A9DF9B1.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Grönblad (1945); Förster (1969); Thomasson (1971, 1977); Uherkovich (1976); Uherkovich & Rai (1979); Sophia & Huszar (1996); Melo et al. (2005); Souza de et al. (2007); Melo & Souza de (2009); Cadima (2013); Cunha de et al. (2013); Feitosa et al. (2015). Western Amazonia (lowlands): Montoya (1974); Díaz-Olarte & Duque (2009).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF89136AC62FBBB0A9DF9B1.taxon	description	DESCRIPTION Cells 30.0 - 32.7 µm long, 23.0 - 23.5 µm wide, isthmus 8.0 µm, cells 1.3 - 1.4 times longer than wide. Cells with deep median constriction, cell wall finely punctate. Ellipsoid semicells, with slightly depressed apices. Each semicell with an axial chloroplast and one central pyrenoid.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF89139AC4DF95D0F88FC72.taxon	description	(Fig. 2 C)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF89139AC4DF95D0F88FC72.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Grönblad (1945); Förster (1974); Uherkovich & Franken (1980); Cadima (2013). Western Amazonia (lowlands): no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF89139AC4DF95D0F88FC72.taxon	description	DESCRIPTION Cells 23.0 - 25.4 µm long, 14.0 - 17.0 µm wide, isthmus 6.0 µm, cells 1.4 - 1.6 times longer than wide. Cells hyaline, with deep median constriction, cell wall finely punctate, median sinus open. Semicells ellipsoid, with lateral margins rounded, vertically convex, apex rounded. One axial chloroplast per semicell.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF89139AC4DF95D0F88FC72.taxon	discussion	REMARKS This is a small taxon within the genus Cosmarium. As mentioned by Moresco et al. (2015) and Fadul-Souza et al. (2022), this variety differs from the type in terms of its smaller size. The size range of our specimens falls within the recorded ranges for the taxon in Grönblad (1945), Krieger & Gerloff (1962), Förster (1974), Moresco et al. (2015), and Fadul-Souza et al. (2022) from various regions in Brazil. The semicells of a morphologically similar taxon, Cosmarium moniliforme Ralfs, are semicircular. This allows these two taxa to be separated.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF79139AFAEFC1B0C2EF9F1.taxon	description	(Fig. 2 D, E)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF79139AFAEFC1B0C2EF9F1.taxon	distribution	DISTRIBUTION. — North and South America. Amazon Basin: Thomasson (1971); Thérézien (1986); Cadima (2013). Western Amazonia (lowlands): Krieger & Scott (1957).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF79139AFAEFC1B0C2EF9F1.taxon	description	DESCRIPTION Cells 196.2 - 212.0 µm long, 126.0 - 127.0 µm wide, isthmus 40 - 42 µm; cells 1.5 - 1.7 times longer than wide. Cell wall denticulate throughout each semicell, with denticles almost always pointing towards apices; central part of semicells with spines and granules (Fig. 2 E). Semicells triangular, with rounded basal angles, straight to slightly convex lateral margins, converging towards the apex of each semicell, and slightly convex to subtruncate apical margins.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF79139AFAFF99D0A8DFD2F.taxon	description	(Fig. 2 F, G)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF79139AFAFF99D0A8DFD2F.taxon	distribution	DISTRIBUTION. — South America. Amazon Basin: Grönblad (1945); Förster (1969); Thomasson (1971); Cadima (2013). Western Amazonia (lowlands): no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF79139AFAFF99D0A8DFD2F.taxon	description	DESCRIPTION Cells 165.0 - 176.5 µm long, 108.0 - 114.5 µm wide, isthmus 35 - 42 µm, cells 1.5 - 1.6 times longer than wide. Cells with deep median constriction, median sinus narrow, closed, and dilated at the apex; cell wall punctate, denticulate at margins and above the isthmus, with central part smooth (clearly shown in Fig. 2 F). Pyramidal semicells with rounded basal angles, occasionally with one prominent denticle at each basal angle, lateral margins straight to slightly convex, converging towards apices; apical angles slightly rounded; apical margin subtruncate to broadly truncate, narrow.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF79139AFAFF99D0A8DFD2F.taxon	discussion	REMARKS This taxon is easily recognizable by having pyramidal semicells, with their apical margins subtruncate to truncate, and by a smooth central part area in the semicells, while the surroundings are punctate. Our specimens’ dimensions coincided with those depicted in Grönblad (1945) but are larger than the specimens described by Förster (1969).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF79139ACA9FCD80A3FF9EF.taxon	description	(Fig. 2 H)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF79139ACA9FCD80A3FF9EF.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Scott et al. (1965); Förster (1969, 1974); Thomasson (1971); Uherkovich (1976); Uherkovich & Franken (1980); Lopes & Bicudo (2003); Melo et al. (2005); Souza de et al. (2007); Melo & Souza de (2009). Western Amazonia (lowlands): Krieger & Scott (1957); Montoya (1974); Duque & Donato (1996 a), Duque & Nuñez-Avellaneda (2000); Nuñez-Avellaneda (2008).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF79139ACA9FCD80A3FF9EF.taxon	description	DESCRIPTION Cells 46.0 - 54.5 µm long, 34.5 - 41.4 µm wide, isthmus 31.0 - 37.0 µm, cells 1.3 times longer than wide. Punctuated cell wall, smooth isthmic region, apical view of cells circular, median constriction not very marked, and shallow median sinus. Subsemicircular semicells, lateral view of semicell same as front. Parietal chloroplast.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF7913BACCFF9970CE8F910.taxon	description	(Fig. 2 I, J)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF7913BACCFF9970CE8F910.taxon	distribution	DISTRIBUTION. — Brazil, Bangladesh. Amazon Basin: Förster (1969); Thomasson (1977). As C. pseudomagnificum f. brasiliense: Förster (1963); Thomasson (1971). Western Amazonia (lowlands): no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF7913BACCFF9970CE8F910.taxon	description	DESCRIPTION Cells 71.7 - 84.9 µm long, 55.4 - 66.8 µm wide, isthmus 24.7 - 30.6 µm, apex 20.2 - 20.4 µm, cells 1.23 - 1.31 times longer than wide. Cell wall with granules, punctuated. Cells are large with deep median constriction; lineal narrow median sinus, slightly widened at apex. Semicells are pyramidal-truncated, with convex lateral margins, with basal sub-rectangular corners and rounded apical corners. Apex broadly truncated, straight. Semicell lateral margins with granules (between 22 and 34); no granules were observed along the apical straight margin of each semicell. Two chloroplasts per semicell.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF7913BACCFF9970CE8F910.taxon	discussion	REMARKS Our specimens coincided with those described originally as C. pseudomagnificum f. brasiliense by Förster (1963) and those reported in Förster (1969) as C. pseudomagnificum var. brasiliense for the Amazon, and with those in Biolo (2016) for the São Paulo State in Brazil by showing cells with similar shapes and size, although our specimens’ size range is slightly larger than those of Biolo (2016) (76 - 81 µm L, 57 - 59 µm W). This species can be confused with Cosmarium binum Nordstedt but differs from it by having a truncated apical margin with no granules, while in C. binum, apical margins are convex with granules (Biolo 2016). Also, C. binum cells are smaller in size and hold a smaller number of lateral granules on each semicell, as described for specimens from Bolivia (Thérézien 1986), and Namibia (Grönblad & Croasdale 1971).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF5913AAFD2F8FC0D59FEEC.taxon	distribution	DISTRIBUTION. — Brazil, Japan, Subantarctic Islands. Amazon Basin: Förster (1969); Thomasson (1977); Aprile & Mera (2007); Cadima (2013). Western Amazonia (lowlands): no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF5913AAFD2F8FC0D59FEEC.taxon	description	DESCRIPTION Cells 64.4 - 66.0 µm long, 42.0 - 42.8 µm wide, isthmus 15.0 µm; cells 1.5 - 1.6 times longer than wide. Cells with oval contour, deeply constricted in the median part, linear median sinus, narrow; pyramidal-subtruncate semicells, lateral margins slightly convex, apex broadly rounded, rounded basal and apical angles, hyaline, densely punctuated cell wall but not as finely as the type variety; axial chloroplast.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF5913AAFD2F8FC0D59FEEC.taxon	discussion	REMARKS Our specimens coincided with the morphological characteristics and size presented by Krieger & Gerloff (1965) in their original description of the taxon. Also, they are similar in size to the populations described by Förster (1969) for the Brazilian Amazon, andOliveira de et al. (2010) for northeast Brazil.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913AAE1EFE980FB1FA53.taxon	description	(Fig. 2 L)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913AAE1EFE980FB1FA53.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Thomasson (1971), Souza de et al. (2007); Cadima (2013). Western Amazonia (lowlands): Araujo (2003); Díaz-Olarte & Duque (2009).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913AAE1EFE980FB1FA53.taxon	description	DESCRIPTION Cells 79.1 - 80.0 µm long, 46.8 - 47.2 µm wide, isthmus 16.6 - 16.9 µm; cells 1.7 times longer than wide. Cells have an oval shape with a profoundly constricted central section, median sinus linear, narrow, dilated at the apex; semicell pyramidal-truncated, with a shallow notch on the median part of the apex; basal angles rounded, lateral margins slightly convex to almost straight, cell wall hyaline, finely punctate; axial chloroplast; one pyrenoid.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913AAE1EFE980FB1FA53.taxon	discussion	REMARKS Our specimens are morphologically similar but larger to the original description of Lundell (1871) and those reported by West & West (1905), Tell & Couté (1993), Oliveira de et al. (2010), and Aquino et al. (2016).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913AAE15FA3C0A83FDCD.taxon	description	(Fig. 2 M)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913AAE15FA3C0A83FDCD.taxon	distribution	DISTRIBUTION. — Brazil, Myanmar, China, Australia, and New Zealand. Amazon Basin: no records. Western Amazonia (lowlands): no records. DeScRiPTiON	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913AAE15FA3C0A83FDCD.taxon	description	Cells 5.9 µm long, 25.4 µm wide, isthmus 9.0 µm; cells as long as wide. Cells with deep median constriction, closed median sinus, straight; subcircular semicells; apical margin straight to broadly rounded; central tumor with warts on the face of the semicell, a variable number of warts in rows around the semicell, without any arrangement; axial chloroplast; two pyrenoids.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913AAE15FA3C0A83FDCD.taxon	discussion	REMARKS This taxon is small and is recognized from the type variety by having a more wavy, irregular cell outline which is given by the presence of more warts. Compared with Cosmarium furcatospermum West & G. S. West, C. quadriverrucosum var. supraornatum has two pyrenoids instead of one. Our specimens are morphologically similar and within size range shown for this taxon in the original description by Skuja (1949) and those reported by Oliveira de et al. (2010) for Brazil and Dingley (2001) for Australia.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913AACB9FD7A0BEFFA73.taxon	description	(Fig. 3 A)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913AACB9FD7A0BEFFA73.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Grönblad (1945); Scott et al. (1965); Förster (1969, 1974); Uherkovich (1976, 1981); Uherkovich & Rai (1979); Melo et al. 2005); Souza de et al. (2007); Melo & Souza de (2009); Souza de & Melo (2010); Cadima (2013). Western Amazonia (lowlands): Duque & Núñez-Avellaneda (2000); Núñez-Avellaneda (2008); Díaz-Olarte & Duque (2009).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913AACB9FD7A0BEFFA73.taxon	description	DESCRIPTION Cells 21.0 - 31.3 µm long, 21.0 - 22.0 µm wide; cells 1.0 - 1.2 times longer than wide. Mostly quadrangular cells, some nearly rectangular, median constriction slightly marked, apical margin slightly depressed; lateral margin parallel to sometimes undulating near isthmus; semicells joined by cylindrical processes.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913DAC72FA1D0AA1F910.taxon	description	(Fig. 3 B)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913DAC72FA1D0AA1F910.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Feitosa et al. (2015). As D. grevillii: Scott et al. (1965); Förster (1969); Thomasson (1971); Melo et al. (2005); Melo & Souza de (2009); Cadima (2013); Cunha de et al. (2013). Western Amazonia (lowlands): Araujo (2003).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913DAC72FA1D0AA1F910.taxon	description	DESCRIPTION Cells 22.6 - 26.1 µm long, 41.1 - 51.0 µm wide, isthmus 37.1 - 47.0 µm; cells 1.8 - 1.9 times wider than long. Pseudofilaments not twisted, cells slightly constricted, apices flat, so there is no cavity between adjacent cells; hyaline cell wall. Median constriction shallow, with a linear or slightly open sinus. Semicells very short, from quadrangular to pyramid truncate outline, lateral margins slightly wavy. Axial chloroplast.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF4913DAC72FA1D0AA1F910.taxon	discussion	REMARKS Our specimens are similar in size range and shape as those reported from Brazil (Aquino et al. 2018) and the British Islands (Brook & Johnson 2002). Similar taxa in shape and size include Desmidium cylindricum Greville ex Nordstedt, but this species has spiral pseudofilaments (Burliga et al. 2016) while those of D. grevillei were not twisted.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF3913CAC90F8FD0CBDFDCD.taxon	description	(Fig. 3 C, D)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF3913CAC90F8FD0CBDFDCD.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Grönblad (1945); Förster (1969); Thomasson (1971); Cunha de et al. (2013). Western Amazonia (lowlands): Ortega et al. (2007).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF3913CAC90F8FD0CBDFDCD.taxon	description	DESCRIPTION Cells 16.0 - 20.8 µm long, 31.3 - 33.9 µm wide; cells 1.6 - 1.9 times wider than long. Pseudofilament triangular, with a single, wavy, dark, longitudinal stripe, formed by the third angle; joints somewhat quadrangular, wider than long, with two slightly angular crenulations on each lateral margin.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF2913CAFFFFD790C2FF931.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Thomasson (1977); Lopes & Bicudo (2003); Melo & Souza de (2009); Cadima (2013); Feitosa et al. (2015). Western Amazonia (lowlands): Araujo (2003); Díaz-Olarte & Duque (2009).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF2913CAFFFFD790C2FF931.taxon	description	DESCRIPTION Cells 44.7 - 46.1 µm long, 28.0 - 33.0 µm wide, isthmus 7.4 - 8.6 µm, apex 28.0 µm; cells 1.3 - 1.6 times longer than wide. Cells with an open median sinus in the distal portion. Semicells sub trapeziform, three-lobed, ornamented with submarginal spines and granules, each basal lobe with one median protrusion with three large tubercular granules, basal corners with one marginal spine. Apical lobe truncated, with a deep medium incision. Axial chloroplast.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF2913CAFFFFD790C2FF931.taxon	discussion	REMARKS Specimens from the Ecuadorian Amazon coincided with the description given by Prescott et al. (1977) and with populations for the Brazilian Amazon by Lopes & Bicudo (2003), Mato Grosso State in Brazil (Camargo et al. 2009), and for the Upper Parana River (Moresco et al. 2015). However, specimens fromMoresco et al. (2015) are slightly wider than ours. Other similar varieties, such as Euastrum abruptum var. subglaziowii, described in Krieger (1937) and Prescott et al. (1977), and also recorded by Moresco et al. (2015) for Brazil, can be separated apart from the type variety by its size proportions (smaller cells) and ornamental characters (no large granules on lateral protrusions of basal lobes).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF2913CAFBDF8DD0D9CFC8F.taxon	description	(Fig. 3 F, G)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF2913CAFBDF8DD0D9CFC8F.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Thomasson (1971). Western Amazonia (lowlands): no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF2913CAFBDF8DD0D9CFC8F.taxon	description	DESCRIPTION Cells 85.1 - 92.5 µm long, 40.8 - 41.0 µm wide, isthmus 12.4 - 13.2 µm; cells 2.1 - 2.3 times longer than wide. Cells with a deep median constriction, punctuated cell wall, closed sinus; trapezoidal semicells; basal lobes slightly rounded, lateral margins with one slight protuberance in the midway between the base and the apex of the cell; truncated to rounded apical lobe with a median notch relatively narrow, closed in each semicell apex.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF2913CAFBDF8DD0D9CFC8F.taxon	discussion	REMARKS Our specimens corresponded well in morphology with those described in Thomasson (1971) for the Brazilian Amazon. As Oliveira de et al. (2011 a) mentioned, the specimens used by Krieger (1937) to describe the variety are larger than their specimens, which coincides with what was found in the present study.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF2913CACADFC770AD0F98E.taxon	description	(Fig. 3 H)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF2913CACADFC770AD0F98E.taxon	distribution	DISTRIBUTION. — Brazil. Amazon Basin: Scott et al. (1965); Förster (1969); Thomasson (1971, 1977); Uherkovich (1976); Martins (1986 b); Melo et al. (2005, 2009); Cadima (2013). Western Amazonia (lowlands): Araujo (2003).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF2913CACADFC770AD0F98E.taxon	description	DESCRIPTION Cells 65.3 - 67.9 µm long, 41.6 - 43.7 µm wide, isthmus 10.2 - 12.0 µm, apex 30.9 - 32.0 µm; cells 1.5 - 1.6 times longer than wide. Cells with a deep median constriction, almost completely enclosed, slightly open at the ends. Trapezoidal semicell, robust, three-lobed, interlobar deep incisions, U-shaped open; lateral and polar lobes with deep recesses in the apex; polar lobe with a deep sinus, V-shaped; apical angles with one to three spines, polar lobes narrower than basal lobes; cell wall hyaline, intramarginal granules, semicellular face with median protrusion formed by four to five granules surrounding one central granule.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF2913EACBAF9370FEFFD8D.taxon	description	(Fig. 3 I)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF2913EACBAF9370FEFFD8D.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Grönblad (1945); Scott et al. (1965); Förster (1969); Uherkovich & Schmidt (1974); Uherkovich (1976, 1981); Thomasson (1977); Uherkovich & Rai (1979); Gutiérrez & Cadima (2004); Melo et al. (2005); Souza de et al. (2007); Melo & Souza de (2009); Souza de & Melo (2010); Cadima (2013); Cunha de et al. (2013); Araújo et al. (2020). Western Amazonia (lowlands): Duque & Núñez-Avellaneda (2000); Núñez-Avellaneda (2008); Díaz-Olarte & Duque (2009); Ismiño et al. (2014, 2018).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF2913EACBAF9370FEFFD8D.taxon	description	DESCRIPTION Cells 16.6 - 17.3 µm long, 24.9 - 27.8 µm wide, isthmus 21.6 µm, cells 1.5 times longer than wide. Cells with shallow median constriction, median sinus open; cell wall hyaline and smooth; apical view circular. Semicells rectangular, with rounded angles and lateral margins straight.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF0913EAE4AFD7A0F88FB73.taxon	description	(Fig. 3 J)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF0913EAE4AFD7A0F88FB73.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Grönblad (1945); Förster (1969, 1974); Thomasson (1971); Martins (1980); Cadima (2013); Cunha de et al. (2013). Western Amazonia (lowlands): Duque & Núñez-Avellaneda (2000); Núñez-Avellaneda (2008).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF0913EAE4AFD7A0F88FB73.taxon	description	DESCRIPTION Cells 15.4 - 27.4 µm long, 14.0 - 14.9 µm wide; cells 1.3 - 1.8 times longer than wide. Cells cylindrical, quadrangular to rectangular in outline, without median constriction. Cell wall hyaline; ornamented below the apex with a double range of granules. Lateral margins smooth, parallel to each other, apical margin slightly rounded.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF0913EAFDEFADC0B1BFDCC.taxon	description	(Fig. 4 A)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF0913EAFDEFADC0B1BFDCC.taxon	distribution	DISTRIBUTION. — South America. Amazon Basin: Martins (1986 b). Western Amazonia (lowlands): Araujo (2003).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF0913EAFDEFADC0B1BFDCC.taxon	description	DESCRIPTION Cells 172.7 - 217.0 µm long, 159.1 - 193.0 µm wide, isthmus 25.0 - 31.7 µm; apex 52.0 - 53.0; cells 1.1 times longer than wide. Cells subcircular in outline, deep median constriction; five-lobed semicells with acute, angular incisions. Hyaline cell wall. Semicells with spines located along the margins of the median sinus and on the margins of lateral and basal lobes and lobules. Polar lobe protruding from the lateral lobes, polar lobes opening gradually towards apex, protruding angles, two-denticulated, curved, divergent; lateral lobes of approximately equal size, each divided into two lobes by a deep incision, each subdivided by three incisions in four parts, with two denticles.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF0913EAFDEFADC0B1BFDCC.taxon	discussion	REMARKS This variety is distinguished from the type variety by the similar development of their lateral and basal lobes, in which both show divisions up to third order lobules. Instead, M. borgei var. borgei show differences between the lateral and basal lobes, with the former developing up to fourth order lobules (Bicudo & Sormus 1982). Compared with Micrasterias sanctipaulensis C. E. M. Bicudo & L. Sormus, M. borgei var. aequalis is larger in size and has spines on the cell wall while the first has a glabrous cell wall (Bicudo & Sormus 1982).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF0913EAC8DFDB90B04FA30.taxon	description	(Fig. 4 B, C)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF0913EAC8DFDB90B04FA30.taxon	distribution	DISTRIBUTION. — South America and China. Amazon Basin: Grönblad (1945); Scott et al. (1965); Förster (1969, 1974); Thomasson (1971); Uherkovich & Rai (1979); Melo et al. (2005); Souza de et al. (2007); Melo & Souza de (2009); Melo et al. (2009); Cadima (2013); Cunha de et al. (2013); Feitosa et al. (2015). Western Amazonia (lowlands): Krieger & Scott (1957); Araujo (2003); Ortega et al. (2007).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF0913EAC8DFDB90B04FA30.taxon	description	DESCRIPTION Cells 264.1 - 278.0 µm long, 235.0 - 243.5 µm wide, isthmus 32.0 - 38.2 µm, apex 53.5 - 58.5 µm; cells 1.1 times longer than wide. Cells with deep median constriction, central sinus closed, slightly open at ends; cell wall finely punctuated, with a number of spines in the middle of the basal part of the semicells, just above the isthmus, with a row of intramarginal spines along the median sinus, others on each side to the left along the deepest incisions. Semicells five-lobed, robust; polar lobe with a deep sinus, a little more than half its length; incisions between lateral lobes open and deep, U- or V-shaped; lateral lobes with consecutive bifurcations to apex, slightly curved denticles, apex divided into two divergent two-denticulated lobules, central denticles slightly oriented towards the sinus; polar lobe larger and more robust than lateral lobes.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF09120AC81F9DD0C02FAD0.taxon	description	(Fig. 4 D)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF09120AC81F9DD0C02FAD0.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: no records. Western Amazon: no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF09120AC81F9DD0C02FAD0.taxon	description	DESCRIPTION Cells 256.0 - 259.5 µm long, 194.1 - 196.1 µm wide; isthmus 33.1 - 36.4 µm; apex: 70.0 - 79.5 µm; cells 1.3 times longer than wide. Cell wall with small denticles, especially along the main incisions, but their arrangement is not always regular. The polar lobe has two two-denticulated marginal apices, which are curved and longer and thinner than the denticles on the lateral lobes; there are two subapical spines on each apical lobule. The terminations of the lateral lobes are truncated, rounded, with the presence of two robust and short denticles, accompanied by at least two shorter and less robust ones. At the concave apical margin of the polar lobes, the cell wall presents a clearly visible fringe of granules.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFF09120AC81F9DD0C02FAD0.taxon	discussion	REMARKS Recent works byNeustupa et al. (2011, 2014) resolved the species delimitation between Micrasterias fimbriata Ralfs, M. rotata Ralfs, M. brachyptera Lundell, and M. apiculata Meneghini ex Ralfs using geometric morphometrics, and genetic analyses. Neustupa et al. (2011) found two phylogenetic lineages for M. fimbriata, one geographically centred in eastern Europe and the British Isles (B-lineage), and one found in North America and western Europe (A-lineage). Our specimens coincided with the B-lineage of M. fimbriata. Posteriorly, Neustupa et al. (2014) described M. compereana to accomodate specimens formerly included within traditional M. fimbriata but with different phylogenetic position and morphological features. According to those authors, M. fimbriata sensu stricto most likely is restricted to temperate and boreal regions of Europe and Asia. As mentioned in Neustupa et al. (2011, 2014) the shape of the terminal lobes is key to identify M. fimbriata, and our specimens clearly present truncated lobes with spines, while surface spine layers on cells can be found in M. fimbriata var. spinosa as well as in M. compereana, so, that last character is not exclusive for M. fimbriata var. spinosa. Our specimens of M. fimbriata var. spinosa are morphologically similar to the drawings of the original description in Roy (1893) but ours are larger in longitude and shorter in breadth, having an elliptic contour instead of being circular.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEE9120AF94FABC0A30FE0F.taxon	description	(Fig. 4 E)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEE9120AF94FABC0A30FE0F.taxon	distribution	DISTRIBUTION. — Europe, North and South America. Amazon Basin: no records. Western Amazonia (lowlands): no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEE9120AF94FABC0A30FE0F.taxon	description	DESCRIPTION Cells 181.5 - 194.2 µm long, 184.0 - 192.5 µm wide, isthmus 19.7 - 22.1 µm, apex 70 - 83.2 µm; cells are as long as wide. Cells with a deep median constriction, median sinus open with acute angles; finely punctuated cell wall. Semicircular semicells, five-lobed, apical lobe slender, and narrowing towards the apex; apical margin slightly concave in the middle region, ends forming two processes elongated, divergent, two-denticulated; lateral and basal lobes forming approximately V-shape incisions; lateral lobes slender, similar to each other, divided into two-denticulated lobules.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEE9120AF94FABC0A30FE0F.taxon	discussion	REMARKS Compared with the type variety, this taxon is larger in size, more circular in shape, polar and lateral lobes are slender, incisions among lobes are deeper, polar lobe with concavity more open, but not as open as in M. radiata var. dichotoma presented in Krieger (1939). Our measurements coincided with those shown by Krieger (1939) yet bigger than those shown in Santos et al. (2016).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEE9120ACD9FDF80A59F9AE.taxon	description	(Fig. 4 F)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEE9120ACD9FDF80A59F9AE.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Grönblad (1945); Thomasson (1971); Lopes & Bicudo (2003); Melo et al. (2005); Cadima (2013); Cunha de et al. (2013). Western Amazonia (lowlands): Krieger & Scott (1957); Montoya (1974); Duque & Donato (1993); Duque & Núñez-Avellaneda (1997); Araujo (2003); Duque & Núñez-Avellaneda (2000); Ortega et al. (2007); Núñez-Avellaneda (2008); Díaz-Olarte & Duque (2009).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEE9120ACD9FDF80A59F9AE.taxon	description	DESCRIPTION Cells 124.0 - 150.6 µm long, 162.0 - 197.1 µm wide, isthmus 40.1 - 44.5 µm; cells 1.3 times wider than long. Cells with a deep median constriction, central sinus closed near the isthmus and then opened; punctuated and hyaline cell wall. Semiorbicular semicell, three-lobed; interlobular incisions opened and deep, V-shaped; apices of the lateral and polar lobes facing to the opening of the sinus, polar lobes bigger than the lateral lobes, angles of the polar lobe acuminated and lateral lobes two-denticulated.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEE9120ACD9FDF80A59F9AE.taxon	discussion	REMARKS Although Bicudo & Sormus (1972) and Santos et al. (2016) mentioned that this taxon is highly polymorphic, especially in the curvature of the polar lobe and the opening of the interlobular incisions, specimens in our populations showed a conservative form.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEE9123ACB3F9560FA2F953.taxon	description	(Fig. 5 A, B)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEE9123ACB3F9560FA2F953.taxon	distribution	DISTRIBUTION. — Brazil (Lopes & Bicudo 2003), Venezuela (Delgado et al. 2003). Amazon Basin: Förster (1969); Uherkovich (1981); Martins (1986 b); Lopes & Bicudo (2003), Melo et al. (2009). Western Amazonia (lowlands): Díaz-Olarte & Duque (2009).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEE9123ACB3F9560FA2F953.taxon	description	DESCRIPTION Cells 137.0 - 153.7 µm long, 116.9 - 161.7 µm wide, isthmus 25.8 - 30.0 µm, apex 67.2 µm. Cell wall with serrated margins; presence of intramarginal spines throughout the cell. Semielliptical semicells, five-lobed, deep incisions; polar lobe sharply projecting beyond the lateral lobes.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFED9122AFCAF95B0C62FC8D.taxon	distribution	DISTRIBUTION. — Pantropical. Amazon Basin: Thomasson (1971). As M. radiata var. brasiliensis: Grönblad (1945); Förster (1969); Uherkovich & Schmidt (1974); Uherkovich (1976, 1981); Uherkovich & Rai (1979); Gutiérrez & Cadima (2004); Melo et al. (2009). As M. furcata: Cadima (2013). Western Amazonia (lowlands): no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFED9122AFCAF95B0C62FC8D.taxon	description	DESCRIPTION Cells 146.0 - 160.4 µm long, 131.0 - 151.1 µm wide, isthmus 18.2 - 20.1 µm, apex 54.7 - 56.6 µm; cells are 1.1 times longer than wide. Cells with deep median constriction, median sinus open with acute angles, cell wall finely punctate. Semicircular semicells, five-lobed, apical lobe about subrectangular, apical margin concave, tips forming two elongated, divergent processes, with two curved teeth; lateral and basal lobes about V-shaped, similar to each other, divided into two-tooth lobules. One remarkable characteristic of all second order lobules, is that they are widened at their base, slightly tapering towards their apices, where they are divided into two curved teeth.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFED9122AFCAF95B0C62FC8D.taxon	discussion	REMARKS This taxon has been subjected to a long taxonomic confusion wandering continuously between M. radiata Hassall ex West & G. S. West, M. radians W. B. Turner, M. furcata C. Agardh ex Ralfs, and their varieties. Coesel & van Geest (2014) finally provided a valid positioning of the taxon into M. radians var. brasiliensis, providing an insightful discussion on the gradual differences among varieties of the Micrasterias radians complex. In our specimens, the apical lobes protrude slightly, while in Coesel & van Geest (2014) those lobes are markedly outstanding; also, teeth on apical lobules are longer than those observed in our specimens, although all other morphological characteristics and size range shown by these authors were very similar to our specimens. From the specimens in our samples, we can add that all second order lobules show a continuous tapering from their base towards the point where they diverge into teeth, which is also observed in Coesel & van Geest (2014) for the same taxon, in Blanco & Sánchez (1986) for M. radiata var. brasiliensis, and in Bourrelly & Couté (1982) for M. radiata var. radiata.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEC9122AF85FC7A0CBCF8F1.taxon	description	(Fig. 5 D, E)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEC9122AF85FC7A0CBCF8F1.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Thérézien (1986); Cadima (2013). As M. radiosa var. ornata f. elegantior: Förster (1969). As M. radiosa var. ornata f. ornata: Martins (1986 b). Western Amazonia (lowlands): Duque & Núñez-Avellaneda (2000) and Núñez-Avellaneda (2008) as M. radiosa var. ornata f. ornata.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEC9122AF85FC7A0CBCF8F1.taxon	description	DESCRIPTION Cells 251.8 - 262.0 µm long, 238.1 - 265.1 µm wide; isthmus 23.6 - 28.0 µm; apex: 41.0 - 43.0 µm; cells 1.15 times longer than wide. Cells with a deep median constriction, semiopen median sinus; ornamented cell wall with intramarginal denticles arranged along half of the basal margins of each semicell. Semicircular semicells, five-lobed, apical lobe subrectangular, elongated, apical margin chamfered in median region, extremities two-denticulated, lateral and basal lobes elongated, V-shaped, similar to each other, divided into lobes two-denticulated.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEC9122AFF8F89E0D8AFBF3.taxon	description	(Fig. 5 F)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEC9122AFF8F89E0D8AFBF3.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Förster (1969); Lopes & Bicudo (2003); Gutiérrez & Cadima (2004); Cadima (2013); Cunha de et al. (2013). Western Amazonia (lowlands): no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEC9122AFF8F89E0D8AFBF3.taxon	description	DESCRIPTION Cells 159.0 - 162.2 µm long, 157.3 - 158.0 µm wide, isthmus 15.2 - 18.3 µm, apex 42.3 µm; cells as long as they are wide. Cells with a deep median constriction, central sinus almost entirely closed, opening only at the ends. Semicircular semicell, five-lobed; polar lobe with linear incision until near of the isthmus; slightly open and deep between the polar lobes; lateral lobes with consecutive bifurcations; polar lobe with V-shaped sinus, apex divided into two divergent lobules two-denticulated, polar lobe with the same size as the lateral lobes. Very deep lobular incisions between polar lobes and lateral lobes, and between lateral lobes and basal lobes.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEC9122AFF8F89E0D8AFBF3.taxon	discussion	REMARKS Specimens analyzed here are morphologically consistent with the descriptions, drawings, and pictures shown by Förster (1969) and Lopes & Bicudo (2003) for the Amazon, Bicudo & Sormus (1982) for São Paulo, and Santos et al. (2016) for Bahia in Brazil.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEC9122ACE3FB9B0B61F836.taxon	description	(Fig. 6 A)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEC9122ACE3FB9B0B61F836.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Grönblad (1945); Thomasson (1971); Uherkovich (1976, 1981); Martins (1986 b), Lopes & Bicudo (2003); Melo et al. (2005, 2009); Cunha de et al. (2013); Feitosa et al. (2015). Western Amazonia (lowlands): Duque & Donato (1993); Duque & Núñez-Avellaneda (2000); Núñez-Avellaneda (2008).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEC9122ACE3FB9B0B61F836.taxon	description	DESCRIPTION Cells 323.8 - 329.5 µm long, 313.6 - 321.7 µm wide; isthmus 44.2 - 44.5 µm; apex: 65.0 - 71.8 µm; cells are as long as they are wide. Large cells with circular outline, deep median constriction; hyaline cell wall, finely punctuated. Semicells five-lobed, apical lobe projecting slightly beyond the lateral lobes, apical lobe angles laterally projecting, two-denticulated; lateral, and basal lobes in a “ V ” shape, similar between them.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9124AFDEFF380F34FC52.taxon	description	(Fig. 6 B, C)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9124AFDEFF380F34FC52.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Grönblad (1945); Förster (1969); Uherkovich & Rai (1979), Melo & Souza de (2009); Melo et al. (2009), Cadima (2013). Western Amazonia (lowlands): Araujo (2003).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9124AFDEFF380F34FC52.taxon	description	DESCRIPTION Cells 272.0 - 281.4 µm long, 204.6 - 209.5 µm wide; isthmus 31.8 - 39.0 µm; cells 1.3 - 1.4 times longer than wide. Semicells with semicircular outline, five- lobed, deep interlobar incisions, basal and lateral lobes divided into lobules, two- denticulated. Lateral lobes bent upwards, terminal spines unequal, the upper longer. Also, the two spines of the polar lobes distinct, the inner ones longer and curved inwards.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9124AF83FC3B0C3AF991.taxon	description	(Fig. 6 D)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9124AF83FC3B0C3AF991.taxon	distribution	DISTRIBUTION. — South America. Amazon Basin: Grönblad (1945); Scott et al. (1965); Thomasson (1971); Martins (1986 b); Lopes & Bicudo (2003), Cadima (2013). Western Amazonia (lowlands): Araujo (2003).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9124AF83FC3B0C3AF991.taxon	description	DESCRIPTION Cells 235.9 - 254.7 µm long, 222.0 - 233.0 µm wide; isthmus 30.2 µm, apex: 64.0 µm; cells 1.1 times longer than wide. Semicircular semicells, five-lobed, deep interlobar incisions, semiopen, finely punctuated cell wall. All lateral lobules of last order (there are five or six on each side) two-pointed; the lateral lobes are inflated in the inner margins, partially covering each other; polar lobes also two-pointed.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9124AFA4F93E0A7FFE0D.taxon	description	(Fig. 6 E)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9124AFA4F93E0A7FFE0D.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Grönblad (1945); Gutiérrez & Cadima (2004); Cadima (2013). Western Amazonia (lowlands): Montoya (1974).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9124AFA4F93E0A7FFE0D.taxon	description	DESCRIPTION Cells 400.0 - 427.3 µm long, 66.0 - 68.5 µm wide; isthmus 31.0 - 34.0 µm; apex: 32.0 - 33.1 µm; cells are 6 - 7 times longer than wide. Cells solitary, dark brown cell wall, with a deep constriction dividing the cell into two semicells, each with four inflates or bulges gradually tapering from base to tip; apices dilated, convex truncated, with a crown of eight conical teeth.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9124ACCAFDF90B08FAD0.taxon	description	(Fig. 6 F-H)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9124ACCAFDF90B08FAD0.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Grönblad (1945); Förster (1969); Thomasson (1971); Uherkovich & Franken (1980); Sophia & Huszar (1996), Gutiérrez & Cadima (2004); Cadima (2013); Cunha de et al. (2013). Western Amazonia (lowlands): Montoya (1974); Araujo (2003).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9124ACCAFDF90B08FAD0.taxon	description	DESCRIPTION Cells 427.0 - 596.0 µm long, 28.0 - 31.0 µm wide; isthmus 20.7 - 24.3 µm; apex: 16.0 - 23.2 µm; cells 15 - 19 times longer than wide. Cells solitary; cell wall hyaline, punctate. Semicells cylindric, slightly and gradually attenuated towards the apices, with a single well-defined basal inflation and rarely with a single undulation above it; lateral margins straight or slightly convex, apices truncately rounded, smooth.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9127AC64FA7C0F5AFE0C.taxon	description	(Fig. 7 A)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9127AC64FA7C0F5AFE0C.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Förster (1969); Thomasson (1971); Uherkovich & Schmidt (1974); Uherkovich (1976, 1981); Sophia & Huszar (1996); Melo et al. (2005); Cadima (2013). Western Amazonia (lowlands): no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9127AC64FA7C0F5AFE0C.taxon	description	DESCRIPTION Cells 34.0 - 36.0 µm long, 85.1 - 104.9 µm wide with processes; isthmus: 7.5 - 9.5 µm. Cells are characterized by their apices with two horns arranged in a divergent way. Cells with shallow median constriction, reduced median sinus; smooth cell wall. The ornamentation on the base of the semicells is variable; subtriangular semicells, lateral angles prolonged in long processes, margins irregularly wavy, and always more or less curved upwards.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFEA9127AC64FA7C0F5AFE0C.taxon	discussion	REMARKS The size and morphology of our specimens coincided with those reported by Förster (1969) for the Brazilian Amazon and Tell (1980) for Northern Argentina. This taxon was the one with the higher occurrence among all our sampling sites (it appeared in six out of eight sites) and presented a variable range in cells size, which is fairly common for this taxon (Tell 1980).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AE0DFDF90F2AFAF3.taxon	description	(Fig. 7 B)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AE0DFDF90F2AFAF3.taxon	distribution	DISTRIBUTION. — America, South-west Asia. Amazon Basin: Grönblad (1945); Scott et al. (1965); Förster (1969); Sophia & Huszar (1996). Western Amazonia (lowlands): Krieger & Scott (1957).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AE0DFDF90F2AFAF3.taxon	description	DESCRIPTION Cells 25.4 - 30.4 µm long, 19.7 - 24.7 µm wide; isthmus 9.8 - 13.8 µm; cells 1.5 - 1.9 times longer than wide. Cells small, sinus very open, inwardly acute, slightly constricted; semicells in front view subquadrate to suboval; apical and lateral angles of each semicell produced into short bifid processes with spines.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AE0DFDF90F2AFAF3.taxon	discussion	REMARKS This taxon is somewhat similar to Staurastrum hystrix Ralfs in size and outline, however it can be set apart by the presence of short bifid processes with spines, produced on each semicell’s lateral and apical angles. Our specimens coincided morphologically with those of the original description in Grönblad (1945) and are within the size range given by Scott et al. (1965) and Sophia & Huszar (1996) for the species in the Brazilian Amazon.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AFBAFA9C0BF0FEEF.taxon	description	(Fig. 7 C)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AFBAFA9C0BF0FEEF.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Förster (1969); Cadima (2013); Souza de et al. (2019). Western Amazonia (lowlands): no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AFBAFA9C0BF0FEEF.taxon	description	DESCRIPTION Cells 28.0 - 29.2 µm long, 36.5 - 37.7 µm wide; isthmus: 6.5 - 9.1 µm; cells 1.3 times wider than long. Hyaline cell wall, glabrous at the base of each semicell. Semicells oval, processes short and a pair of spines at the base of each process.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AFBAFA9C0BF0FEEF.taxon	discussion	REMARKS This variety differs from the type variety by having shorter processes and by the presence of two spines at the base of each process. Our specimens correspond in morphology with those reported by Förster (1969) for the Brazilian Amazon, Oliveira de et al. (2016 b) for the northeastern region of Brazil, and Tell (1980) for Argentina, but our specimens were slightly larger than those in Förster (1969) and Oliveira de et al. (2016 b), and slightly shorter than size shown in Tell (1980).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AC51FE980A14FB53.taxon	description	(Fig. 7 D)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AC51FE980A14FB53.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Förster (1969, 1974); Thomasson (1971); Uherkovich & Schmidt (1974); Uherkovich (1976, 1981), Martins (1986 a), Cadima (2013). Western Amazonia (lowlands): no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AC51FE980A14FB53.taxon	description	DESCRIPTION Cells 42.9 - 47.6 µm long (without spines), 62.9 - 63.4 µm long (with spines); 40.2 - 41.9 µm wide (without spines), 62.3 - 63.5 µm wide (with spines); isthmus: 12.2 µm; cells 1.1 times longer than wide. Cells with strong spines, sometimes curved, highly polymorphic, with the number of spines varying from one cell to another, and even from one semicell to another.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AC51FE980A14FB53.taxon	discussion	REMARKS The morphology of our specimens corresponds well with the original description by Grönblad (1945) and with the specimens from Martins (1986 a), both from the Brazilian Amazon, in having two strong spines on the angles of semicells and the presence of slender and slightly curved spines between the strong spines.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AC71FB3B0BEFF831.taxon	description	(Fig. 7 E)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AC71FB3B0BEFF831.taxon	distribution	DISTRIBUTION. — France, Brazil. Amazon Basin: Grönblad (1945); Förster (1969, 1974); Thomasson (1971, 1977); Uherkovich (1976, 1981); Uherkovich & Rai (1979); Martins (1986 a); Melo & Souza de (2009). Western Amazonia (lowlands): no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AC71FB3B0BEFF831.taxon	description	DESCRIPTION Cells 27.1 - 31.7 µm long, 67.6 - 93.0 µm wide with processes, isthmus: 7.8 - 9.6 µm. The basal margin of the inverted triangular semicells features a single granule with two to three teeth positioned just above the isthmus, while the upper margin is indented in the middle. Each angular process boasts a nearly horizontal, diverging spine and an emarginate granule at its base. The processes are slender, long, and diverging, with toothed margins culminating in two or three denticles.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE99127AC71FB3B0BEFF831.taxon	discussion	REMARKS Specimens from this taxon are variable in shape, particularly on the curvature of processes. Like our specimens, Förster’s (1974) hold two or three denticles at the tip of each process.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89126AFA5FF380C74FCD2.taxon	description	(Fig. 7 F)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89126AFA5FF380C74FCD2.taxon	distribution	DISTRIBUTION. — South America. Amazon Basin: Grönblad (1945); Thomasson (1971); Förster (1974). Western Amazonia (lowlands): Krieger & Scott (1957).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89126AFA5FF380C74FCD2.taxon	description	DESCRIPTION Cells 31.2 - 31.6 µm long, 23.8 - 24.3 µm wide; isthmus: 11.8 - 12.6 µm; cells 1.3 times longer than wide. Hyaline cell wall, with spines. Semicells more or less reniform; open median sinus; apical view three-angled.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89126AFB3FC7B0CC2F831.taxon	description	(Fig. 7 G)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89126AFB3FC7B0CC2F831.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Grönblad (1945); Thomasson (1971); Melo et al. (2005); Souza de & Melo (2011); Cadima (2013); Cunha de et al. (2013). Western Amazonia (lowlands): Araujo (2003); Duque & Donato (1996 b); Duque & Núñez-Avellaneda (2000), Núñez-Avellaneda (2008); Díaz-Olarte & Duque (2009).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89126AFB3FC7B0CC2F831.taxon	description	DESCRIPTION Cells 40.0 - 43.7 µm long, 45.0 - 49.7 µm wide (without spines), 70.6 - 73.2 µm wide (with spines); isthmus 10.5 - 13.0 µm. Smooth cell walls. Subellipsoidal semicells, irregularly contoured; deeply constricted, sinus widely open at the extremity, robust and strong spines directed convergently. Apical and lateral sides slightly convex. Semicells slightly different in size.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89126AFB3FC7B0CC2F831.taxon	discussion	REMARKS This taxon is considered to be very polymorphic, presenting high variability in size, semicells shape, length of spines, and spines site of insertion (Coesel & Meesters 2013).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89126AC8AFF380AEBFAF3.taxon	description	(Fig. 7 H, I)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89126AC8AFF380AEBFAF3.taxon	distribution	DISTRIBUTION. — Cosmopolitan. Amazon Basin: Förster (1969, 1974); Thomasson (1971); Uherkovich & Schmidt (1974); Uherkovich (1976, 1981); Uherkovich & Rai (1979); Sophia & Huszar (1996); Huszar & Reynolds (1997); Melo et al. (2005); Souza de et al. (2007); Melo & Souza de (2009); Souza de & Melo (2011); Cadima (2013). Western Amazonia (lowlands): Díaz-Olarte & Duque (2009).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89126AC8AFF380AEBFAF3.taxon	description	DESCRIPTION Cells 25.2 - 25.8 µm long, 18.0 - 20.6 µm wide; isthmus 5.7 - 6.0 µm; cells 1.3 - 1.4 longer than wide. Cells with a deep, wide open sinus. The isthmus is usually elongated; the body of the semicell over the isthmus is triangular. The apex is slightly elevated by a median depression. The apical angles are rounded, and they have long spines that can be parallel, divergent, or convergent (mainly convergent in our specimens).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89126AC8AFF380AEBFAF3.taxon	discussion	REMARKS Our specimens coincided morphologically with descriptions and drawings for the Brazilian Amazon specimens of Staurodesmus triangularis (Förster 1969, 1974; Sophia & Huszar 1996). This taxon has also been considered as highly polymorphic (Bicudo & Azevedo 1977).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89128AC47FA5D0F69FD12.taxon	description	(Fig. 7 J)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89128AC47FA5D0F69FD12.taxon	distribution	DISTRIBUTION. — South America and China. Amazon Basin: as Xanthidium antilopaeum var. mamillosum f. mediolaeve: Grönblad (1945). As X. mamillosum f. mediolaeve: Thomasson (1971). Western Amazonia (lowlands): no records.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89128AC47FA5D0F69FD12.taxon	description	DESCRIPTION Cells 76.4 µm long (115.0 µm with spines), 83.9 µm wide (136.2 µm with spines); isthmus 31.5 µm; apex: 27.7 - 31.7 µm. Cell wall finely punctuated. Semicells hexagonal-pyramidal, sinus linear inwardly, outwardly greatly enlarged. The spines on each semicell are arranged apically and laterally and are strongly inflated at the base. The spines, which are strong, straight, and long, become sharper towards the ends.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE89128AC47FA5D0F69FD12.taxon	discussion	REMARKS This taxon is easily identifiable by the well-defined inflated base of spines in our specimens. Although our specimens are slightly smaller than those described by Grönblad (1945) from the Amazon, and Bourrelly & Couté (1982) from French Guyana, they are slightly larger in cells longitude than those shown by Camargo et al. (2009) for Mato Grosso, Brazil (as Xanthidium antilopaeum var. mamillosum f. mediolaeve Grönblad). The size of our specimens falls within the wide range of variation exhibited by specimens reported by Oliveira de et al. (2011 b) for northeastern Brazil. As recorded in those other works, X. mamillosum var. mediolaeve presents a high variation in size.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE69128AE28FCFA0C6DFA70.taxon	description	(Fig. 7 K, L)	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE69128AE28FCFA0C6DFA70.taxon	distribution	DISTRIBUTION. — South America and Caribbean Islands. Amazon Basin: Grönblad (1945); Förster (1969, 1974); Thomasson (1971); Uherkovich (1976, 1981); Lopes & Bicudo (2003); Gutiérrez & Cadima (2004); Melo et al. (2005); Souza de et al. (2007); Melo & Souza de (2009); Souza de & Melo (2011); Cadima (2013). Western Amazonia (lowlands): Núñez-Avellaneda & Duque (2000), Araujo (2003); Díaz-Olarte & Duque (2009).	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
C7390B66FFE69128AE28FCFA0C6DFA70.taxon	description	DESCRIPTION Cells 66.7 - 71.4 µm long, 63.0 - 71.9 µm wide; isthmus 16.5 - 17.3 µm; cells are as long as they are wide. Semicells subhexagonal, angled with cylindrical processes, short, twospined, rhomboid apical view, smooth cell wall. With spines and a well individualized polar lobe. Open sinus, ornamentation varies slightly from cell to cell, as well as between semicells. The apical lobe has four slightly curved spines. Lateral lobes always present a pair of recurved spines.	en	SÁNCHEZ, Luzmila, SÁNCHEZ, Fernando R., RÍOS-TOUMA, Blanca, José V. MONTOYA (2025): Desmidiales (Desmidiaceae, Zygnematophyceae) from lowland rivers and floodplain lakes of Ecuadorian Amazonia. Cryptogamie, Algologie 20 (3): 31-60, DOI: 10.5252/cryptogamie-algologie2025v46a3, URL: https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/algologie2025v46a3.pdf
