Astasia klebsii (Lemmermann, 1910)
Most likely ID: n.a.
Synonym: n. a.
Sampling location: Simmelried
Phylogenetic tree: Astasia klebsii
- body spindle shaped
- length 50–60 µm (of elongated cell)
- one flagellum of body length
- eyespot absent
- paramylon bodies egg-shaped
- very active euglenoid movement
- a disc-shaped broadening of the body moves to the posterior end
- body can twist along the longitudinal axis
posterior end always rounded
- weak striation of pellicle
Astasia klebsii is very common in the Simmelried. Unfortunately I have photographed this colorless euglenid flagellate only rarely. The photographs shown below (s. fig. 1 a-e) were taken in December 2006.
The name of the genus is derived from “Astasis”, which medically means the inability of motor coordination. In fact, Astasia klebsii is extraordinarily metabolic and in constant motion. It is dominated by a disc-shaped widening of the anterior end, which moves in a wave-like manner to the posterior end. But also a twisting of the body along the longitudinal axis is possible. Other characteristic features of Astasia klebsii are the body length of 50–60 µm (of the elongated specimens, s. fig. 1a), the egg-shaped paramylon grains and the flagellum approximately of body length. In all metabolic movements the posterior end remains rounded and does not form a tip.
Fig. 1 a-e: Astasia klebsii. L = 58 µm (of elongated specimen, a). Different stages of the metabolic movement of a freely swimming specimen. EP = egg-shaped paramylon grains, F = flagellum, Nu = nucleus. Obj. 60 X.