Caenomorpha lauterborni (Kahl, 1927)
Most likely ID: n.a.
Synonym: n.a.
Sampling location: Simmelried
Phylogenetic tree: Caenomorpha lauterborni
Diagnosis:
- body medusoid with two spines
- primary spine straight and thin with a pointed distal end
- secondary spine is slighty flattened and curved towards the central longitudinal axis
- a curved ridge runs to the secondary spine
- length 60–70 µm
- macronucleus globular or ovoid with an adjacent micronucleus
- on right side of the dome two rows of cirri
- without somatic cilia except a small field of cilia at the base of the primary spine
- adoral zone runs in a furrow and encircles the body spirally
- mouth opening in mid-body, cytopharynx directed anteriorly
- one contractile vacuole located at the base of the secondary spine
Among the caenomorphid ciliates Caenomorpha lauterborni is one of the smaller species. I have found it so far only in the mud zone of the Simmelried. Possibly I have overlooked the species in the other localities so far, due to the small size and because Caenomorpha lauterborni is a fast swimmer. In addition, the species is coverslip sensitive, which makes it difficult to examine living individuals.
A characteristic feature of Caenomorpha lauterborni is a distinct ridge, which originates from the secondary spine, runs across the right side to the ventral side (s. arrows in drawings 1 and 3 above and fig. 1 c). In addition, the contractile vacuole is located at the base of the secondary spine (s. fig. 1 b) and not of the primary spine. The secondary spine is slightly offset from the central longitudinal axis toward the margin. While the primary spine is narrow and straight with a distinct tip, the secondary spine is somewhat flattened and distinctly curved toward the central, longitudinal axis (s. fig. 1c).
Fig. 1 a-d: Caenomorpha lauterborni. L = 64 µm. A freely swimming specimen from the left side. Note the distinct ridge (c, arrows) running from the ventral side to the secondary spine (SS). AZM = adoral zone of membranelles, CV = contractile vacuole, Ma = macronucleus, Mi = micronucleus, PC = perizonal cilia, PS = primary spine. Obj. 60 X.