image : © Henk Schulp
Micrasterias apiculata as recently encountered in a mesotrophic Dutch quivering fen.
Cell dimensions (L x B): ca 250 x 225 µm
M. apiculata resembles M. fimbriata but differs in a denser and more pronounced pattern of cell wall spines. In particular the presence of an elevated, star-like, supraisthmial group of spines is most characteristic. In the Netherlands M. apiculata was reported by Prof. J. Heimans from a number of Pleistocene pools, in the first decades of the last century. Any later record was wanting until recently when it was encountered in a small, mesotrophic, quivering fen, next to some ten other Micrasterias species (Coesel, 2004).
image © Henk Schulp
Detail of cell showing the species-characteristic, supraisthmial group of spines.
Mouse over images © Alfred van Geest (after Austrian material)
Another cell of Micrasterias apiculata well shownig the pattern of small cell wall spines.
Reference:
Coesel, P., 2004. Bijzondere sieralgvondsten in ‘De Wieden’ (with abstract in English). — Gorteria (in press).