Micrasterias arcuata var. perforata Kurt Först. & F.Eckert (1964: 373)

Ramos, Geraldo José Peixoto, Costa, Fabiana De Matos, Santos, Maria Aparecida Dos & Moura, Carlos Wallace Do Nascimento, 2019, Taxonomic novelties, new records, and rare species of desmids from the Chapada Diamantina region, Brazil, Phytotaxa 391 (3), pp. 185-196 : 192

Micrasterias arcuata var. perforata Kurt Först. & F.Eckert (1964: 373) ( Figs 47–50 )

Cell dimensions: length 42–45 μm, breadth 37–40 μm, apical lobe 25 μm, isthmus 10–12 μm.

Habitat characteristics: River; quiet and warm waters, associated to filamentous algae.

Material examined: HUEFS 244148.

Notes: Taxon rare, reported only in the original publication ( Förster 1964), occurring in Serra da das Almas , between the states of Bahia and Minas Gerais, Brazil. We observed slight morphological variations in the basal lobe during our analyses, ranging from straight to slightly curved (the latter more common). Additionally, we found an elliptic zygospore identical to that reported by Förster (1964).

Figures

FIGURES 28–50. Euastrum piataense (28–34): LM (28–31), SEM (33,34), ventral view (28–30, 33), lateral view (31,34) apical view (32); Euastrum subcyclopicum var. elongatum (35–39): LM (35–38), SEM (39), ventral view (35–36, 39), lateral view (37), apical view (38); Euastrum bicudoi (40–42): ventral view (40), lateral view (41), apical view (42); Euastrum subtrilobulatum var. laeve (Figs 43–46): ventral view (43,44), lateral view (45), apical view (46); Micrasterias arcuata var. perforata (47–50): LM (47–49), SEM (50), zygospore (49). Scale bar 10 μm.