Desmid of the month
March 2006
Euastrum humerosum
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Euastrum oblongum (desmid of
December 2004) Euastrum humerosum belongs to the group of Euastrum
species in which the median apical incurvation is in the form of a deep,
closed invagination. Semicells are about pyramidal in outline with rather
deep incurvations separating apical, lateral and basal lobes. The basal
lobes in their turn are incurved too, so more or less doubled. In the
Netherlands both the nominate variety and var. affine (characterized
by deeper lateral incurvations) are of occasional occurrence in acidic,
oligotrophic moorland pools.
Euastrum humerosum var. humerosum
Cell dimensions (L x B): ca 130 x 70 µm
