Image © Henk Schulp
Cell of Micrasterias brachyptera. Note the relatively short, compact lateral lobes distinctly separated from the apical lobe, giving the impression of being ‘wings’.
Cell dimensions (L x B): ca 210 x 150 µm
In former days Micrasterias brachyptera, like M. fimbriata, was considered a variety of M. apiculata (West & West 1905). Although their mutual relationship is obvious, the taxa in question are hardly or not interconnected by transitional forms, so a status of separate species seems reasonably justified. Micrasterias brachyptera differs from the other two species mentioned in that the lateral lobes are relatively short, so that the cell body gives the imprssion of being provided with wings (‘brachy-ptera’ literally means ‘with short wings’). In the Netherlands M. brachyptera is exclusively known from the north-western corner of the province of Overijssel where it is of occasional occurrence in mesotrophic quaking fen hollows.
Image (stack) © Koos Meesters (after Lofoten material).
Another cell of Micrasterias brachyptera showing various parts in more detail.
Reference:
West, W. & G.S. West, 1905. A monograph of the British Desmidiaceae. Volume 2. — Ray Society, London, 204 pp.