Filament of Spondylosium pulchellum. Notice the loose intercellular connections.

Mean cell dimensions (L x B): 17 x 15 µm



Desmid of the month
April 2007

Spondylosium pulchellum

As suggested  elsewhere (see Spondylosium ellipticum), the filamentous genus  Spondylosium  is rather artificial in nature. Whereas cells of most Spondylosium species are Cosmarium-like, cells of Sp. pulchellum resemble those of given small-sized Euastrum species, like Eu. validum or Eu. sublobatum. As intercellular connections in Sp. pulchellum filaments are readily to be broken, often only scattered, separate cells are encountered.  On the other hand, whole filaments may be attached  to a solid substrate by means of a short, gelatinous basal stalk, a phenomenon that seems to be characteristic of this species (West et al., 1923: 228). In the Netherlands, Sp. pulchellum is of rather common occurrence  in oligotrophic, acidic moorland pools.

Extra long filament of Sp. pulchellum

Extra long filament of Sp. pulchellum


West, W., West,  G.S. & Carter, N., 1923. A monograph of the British Desmidiaceae, vol. V. — Ray Society, London

Filament of Sp. pulchellum attached to solid substrate by a gelatinous basal stalk (phase contrast)

SEM picture of Spondylosium pulchellum showing a scrobiculate cell wall.

Spondylosium pulchellum, detail of cell wall showing some small pores in between the scrobicles.