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.



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.

Series of S. erythrocephala cells embedded in a common mucilage envelope.

two other cells of Spirotaenia erythrocephala
Image © RIZA

Two other cells of S. erythrocephala, with rather loosely twisted chloroplasts.