Rhabdomonas incurva (Fresenius, 1858)
Most likely ID: n.a.
Synonym: n. a.
Sampling location: Simmelried
Phylogenetic tree: Rhabdomonas incurva
Diagnosis:
- cell short, bean-shaped
- anterior end rounded or obliquely truncate, posterior end rounded
- Ventral side weakly concave, dorsal side curved
- length 13–25 µm
- one flagellum, about body length
- furrows of the pellicle widely spaced, only slightly twisted
- several paramylon grains, often 2–3 larger grains
- nucleus at posterior end
I have found Rhabdomonas incurva only rarely in the Simmelried. After 2010 I could not detect the species anymore. Rhabdomonas incurva belongs to the Euglenophyceae and is easily recognized by its slightly bean-shaped appearance. The furrows on the pellicle are sometimes difficult to see when the cell is filled with many paramylon grains. Rhabdomonas differs from the genus Menoidium in the shape of the cell cross-section. While the cells of Rhabdomans are almost circular in cross-section, members of the genus Menoidium are strongly laterally flattened.
Fig. 1 a-b: Rhabdomonas incurva. L = 16 – 19 µm. Two focal planes of two specimens. The smaller specimen (b) is 16 µm long and the larger on 19 µm (b). Note the slightly twisted furrows of the pellicle (b). Obj. 100 X.