Kerona pediculus
(Müller, 1773) Müller, 1786
Most likely ID: n.a.
Synonym: Kerona polyporum
Sampling location: Pond of the waste disposal company Constance
Phylogenetic tree: Kerona pediculus
Diagnosis:
- body kidney-shaped, dorso-ventrally flattened
- length 130–205 µm
- adoral zone about 50 % of body length
- two ellipsoidal macronuclei
- each macronucleus with a spherical micronucleus, clearly separated
- contractile vacuole on left margin, below mouth
- 6 slightly curved frontoventral rows of cirri
- 4–6 buccal cirri
- 5 transverse cirri
- 3 caudal cirri
Kerona pediculus is an ectocommensal ciliate, living on various Hydra species, and creeps on them rapidly. The species is feeding on algae and ectodermal cells from Hydra.
Because it lives on Hydra, Kerona pediculus cannot be confused with any other species. The body is kidney-shaped and has a complicated ciliature. However, the diagonal rows of frontoventral cirri and the transvers cirri are easily recognizable (s. fig. 1 b). The three caudal cirri are difficult to recognize and I was also unable to clearly identify the buccal cirri.
Kerona pediculus has two ellipsoidal macronuclei. Each macronucleus is associated with a spherical micronucleus, which is clearly separated from the macronucleus (s. fig. 2 b). The adoral zone extends approximately to the middle of the body (s. fig. 2 a).
More images and information on Kerona pediculus: closterium_mysterium-iNaturalist-Kerona pediculus
Fig. 1 a-b: Kerona pediculus. L = 134 µm. Two focal planes from ventral. The diagonal running frontoventral cirri (FVC) are visible as well as two of the 5 transverse cirri (TC). Obj. 60 X.
Fig. 2 a-b: Kerona pediculus. L = 134 µm. Focal plane on the adoral zone of membranelles (AZM) and the two macronuclei (Ma 1, Ma 2) with two, clearly separated micronuclei (Mi 1, Mi 2). Obj. 60 X.