Diagnostic features
Filamentous desmid with short nearly-cylindrical cells joined end to end (there is a constriction dividing each cell into two semi-cells, but it is slight). Each semi-cell has one axial, radial chloroplast with pyrenoids. The two chloroplasts per cell are separated by a clear area in which the nucleus may be visible. May posses a wide mucilage sheath and fine fibrils extending from the cell walls.
![[Hyalotheca], Lake Tuakitoto, X640. Photo: Otago Regional Council & Manaaki Whenua Image](/assets/Tools-And-Resources/Identification/algae/hyalotheca640__ScaleWidthWzEwMjRd.jpg)