Uroleptus caudatus
(Claparède & Lachmann, 1858) Kahl, 1930
Most likely ID: n.a.
Synonym: Paruroleptus caudatus
Sampling location: Ulmisried, Purren pond, Simmelried
Phylogenetic tree: Uroleptus caudatus
Diagnosis:
- body long elliptical, clearly tailed, front broadly rounded
- length about 120–350 µm
- adoral zone about a fifth of body length
- contractile vacuole on left margin, level of mouth
- two ellipsoidal macronuclei with one micronucleus each
- 2 rows of midventral cirri
- right and left marginal rows of cirri
- 3–5 transverse cirri
- 3 frontal cirri
- 1 bucaal cirrus
Uroleptus caudatus is a fairly common hypotrichous ciliate that I find in various locations. The specimens are usually found in floating or decomposing plant material.
The specimens in my population usually have a length of approx. 200 µm. The body is slender with a clearly developed tail. Dorsally 4 longitudinal rows of cirri can be recognized. The two middle rows are the midventral cirri (s. figs. 3 and 5 b). To the right and left of these are the marginal rows of cirri (s. figs. 3 and 5 b). Rigid, bristle-like cilia can often be seen on the edge of the body (s. fig. 2 a). These are the dorsal, marginal cilia, which are recognizable at the margin of the body.
The similar species Uroleptus piscis is larger (up to 500 µm), has 3 caudal cilia and the cirri of the left marginal row are clearly elongated near the posterior end. Uroleptus musculus can also be confused with Uroleptus caudatus. However, this species does not have a caudal process.
More images and information on Uroleptus caudatus: Michael Plewka-Freshwater life-Uroleptus caudatus
Fig. 1 a-d: Uroleptus caudatus. L = 206 µm. Different focal planes of a freely swimming specimen. CV = contractile vacuole. Obj. 40 X.
Fig. 2 a-b: Uroleptus caudatus. L = 192 µm. Two focal planes of a freely swimming specimen. The bristle like lateral cirri are the left and right dorsal marginal cirri (RDC, LDC). AZM = adoral zone of membranelles, UM = undulating membrane. Obj. 100 X.
Fig. 3: Uroleptus caudatus. L = 198 µm. Dorsal view on the two rows of ventral cirri (VR) and the left and right rows of marginal cirri (LMR, RMR). Obj. 100 X.
Fig. 4: Uroleptus caudatus. The oral apparatus in detail. On the left side the undulating membrane (UM) is visible and on the right side the adoral zone of membranelles (AZM). FC = frontal cirri, BC = buccal cirrus. Obj. 100 X.
Fig. 5 a-b: Uroleptus caudatus. Tweo focal planes of a slightly squashed specimen. CV = contractile vacuole; Ma 1, Ma 2 = macronuclei; Mi 1, Mi 2 = micronuclei; VC = ventral rows of cirri; LMR = left marginal row of cirri; RMR = right mariginal row of cirri. Obj. 100 X