Desmodesmus brasiliensis

(Bohlin) Hegewald, 2000

Most likely ID: n.a.

 

Synonym: Scenedesmus brasiliensis

 

Sampling location: Lake Constance

 

Phylogenetic tree: Desmodesmus brasiliensis

 

Diagnosis: 

  • coenobia of (2)–4–(8), linearly arranged cells
  • cells elongated oval to cylindrical
  • length of cells 9–28 µm, width 2–8.5 µm
  • (1)–2–4 longitudinal, continuos ridges per cell (sometimes absent)
  • inner and outer cells with short teeth at the apices
  • margins of the outer cells smooth
  • one pyrenoid per cell
Desmodesmus-brasiliensis
Desmodesmus brasiliensis

I have found Desmodesmus brasiliensis in the plankton of Lake Constance in July 1994. The main characteristics of Desmodesmus brasiliensis are the short teeth at the apices (s. fig. 1 a) and the continuous ridges at the sides of the cells (s. fig. 1 b).

 

The very similar species Desmodesmus lefevrei (synonym = Scenedesmus lefevrei) can be distinguished from Desmodesmus brasiliensis by a fringe of small teeth at the margins of the outer cells (s. Michael Plewka-Freshwater life-Scenedesmus lefevrei).

Desmodesmus-brasiliensis

Fig. 1 a-b: Desmodesmus brasiliensis. L = 19 µm (of coenobium). Two focal planes of a coenobium of 4 cells. Note the short teeth at the apices of the cells (a) and the continuous ridges on the sides of the cells (b). Obj. 100 X.