Astasia dangeardii
Lemmermann, 1910
Most likely ID: n.a.
Synonym: n.a.
Sampling location: Simmelried
Phylogenetic tree: Astasia dangeardii
Diagnosis:
- cell metabolic, spindle shaped or club-shaped
- length 30–60 µm (of elongated cell)
- posterior end gradually tapered, tail-like
- one flagellum of body length
- eyespot absent
- paramylon bodies oval, egg-shaped or rod-shaped
- distinct striation of pellicle, running counterclockwise
- nucleus in posterior half of cell
I rarely find Astasia dangeardii in the Simmelried. The species can be recognized by its rather impressive size of about 60 µm, its beet-shaped form and above all by the clearly visible striation of the pellicle. Among the described species of the genus Astasia there are only a few that reach a length of 60 µm. These have either only a very delicate striation of the pellicle (Astasia skadowskii) or they are very strongly metabolized and do not take a beet-shaped form (Astasia fustis and Astasia curvata). My specimens were only very slightly metabolic. In general, they contracted along the longitudinal axis, thickening the center of the body. I did not observe any torsion or flattening of the cells.
Fig. 1 a-f: Astasia dangeardii. L = 64 µm (of elongated cell). Different stages of the metabolic movement of a freely swimming specimen. CV? = probably the contractile vacuole, F = flagellum, Nu = nucleus, NUC = nucleolus, PG = oval paramylon grains, SP = striation of pellicle. Obj. 100 X.