Desmid of the month
February 2007
Spirotaenia erythrocephala
The saccoderm
desmid Spirotaenia erythrocephala is marked by fusiform cells and a
chloroplast that is coloured reddish at its ends, giving rise to the species
name erythrocephala (erythro, from Greek ‘eruthros’, = red; cephalo,
from Greek kephalo, = head). The chloroplast is in the form of a broad, spiralling
tape making 2-4 turns (depending on the steepness and the closeness of the
turns). Spirotaenia cells are often met with in pairs as, after cell
division, daughther cells are incorporated by a common mucilaginous sheath.
Not seldom, even quite a colony of cells may be encountered. In the Netherlands, Spirotaenia erythrocephala is of occasional occurrence in various shallow,
mesotrophic water bodies.
Image © Henk Schulp
Two cells of Spirotaenia eryhtrocephala. Note the parietal, closely spiralled chloroplast tape that is coloured slightly reddish at the ends.
Cell dimensions (L x B): ca 50 x 8 µm.
