Spirotaenia endospira Archer, 1864
Most likely ID: n.a.
Synonym: n.a.
Sampling location: Sima Moor (Austria)
Phylogenetic tree: Spirotaenia endospira
Diagnosis:
- cells oblong with broadly rounded ends
- several cells in common gelatinous sheath
- cell wall smooth
- length 10–25 µm, width 7–8 µm
- cells 3.5–4.5 times longer than wide
- one spirally curled chloroplast, 1–3 coils
- several pyrenoids
I found Spirotaenia endospira in the Sima Moor (Austria). The cells occur in accumulations of several cells in a common gelatinous sheath (s. fig. 1 a-b). At low magnification the species can be confused with small species of the genera Mesotaenium or Cylindrocystis. However, the chloroplast of Spirotaenia endospira is spirally curled what can be clearly reconized at hight magnification (s. figs. 2 a-b and 3 a-b).
Fig. 1 a-b: Spirotaenia endospira. L = 9–19 µm (of cells). An accumulation of 15 cells in a common gelatinious sheath. Obj. 40 X.
Fig. 2 a-b: Spirotaenia endospira. L = 20–23 µm. Two focal planes of some cells. Note the curled chloroplast (Chl). Obj. 100 X.
Fig. 3 a-b: Spirotaenia endospira. L = 20–24 µm. Two focal planes of a second group of cells. Obj. 100 X.