| Division | Charophyta |
| Class | Zygnematophyceae |
| Order | Zygnematales |
| Family | Mesotaeniaceae |
| Basionym | Penium naegelii Brébisson and Archer |
| Synonym | Netrium digitus var. naegelii (Brébisson & Archer) Willi Krieger |
Cells larger in size, cells oblong to lanceolate with broadly truncately rounded apices, 3-5.5 times longer than broad. Lobes usually bent alternately as left and right side of the cells. Cell measures 100-280 μm in length and 40-110 μm in breadth. Cell consists of two Chloroplasts with longitudinal ridges.
Ecology
Occurs in oligo-mesotrophic water bodies and commonly observed in acidic habitats.