Stentor

Abstract

Stentor, the trumpet animalcule, is a single‐celled organism (protist) belonging to the ciliates (Ciliophora). It is interesting because of its trumpet shape, commonness, comparatively large size (∼1 mm), attractive coloration and high regeneration capacity.

Keywords: ecology; learning; ciliates; regeneration; bioassay

Figure 1.

A Stentor assemblage showing the main shape and macronucleus types (from Curds et al., modified). (a) Large (1–4 mm), slenderly trumpet‐shaped species with a vermiform and a moniliform macronucleus, respectively. (b) Freely motile, turbinate specimen with coloured pigment stripes. (c) Small to medium‐sized (100–1000 μm), broadly trumpet‐shaped species with single, spherical macronucleus. (d) Campanulate species.

Figure 2.

An almost fully extended Stentor niger adhering to the microscope slide (courtesy of M. Kreutz, Germany). This beautiful species is up to 1 mm long, has a single globular macronucleus (MA), and is yellow‐brown due to brownish pigment granules. Note the mighty adoral zone of membranelles (AZM), which swirls food particles into the huge buccal cavity (BC). AZM, adoral zone of membranelles; BC, buccal cavity; CR, ciliary rows; CV, contractile vacuole; FV, food vacuole; L, lorica; MA, macronucleus; PB, peristomial bottom; PS, pigment stripes; SC, sensory cilia.

Figure 3.

Stentor multiformis (a, d) and S. amethystinus (b, c), both slightly squashed to show details of the organization (courtesy of M. Kreutz and P. Mayer, Germany). S. multiformis is a small species (length about 250 μm when fully extended) with beautiful blue pigment stripes and a single globular macronucleus. The individual pigment granules are blue and about 1 μm across. The narrow white zones between the pigment stripes contain the ciliary rows. S. amethystinus is a medium‐sized species (up to 500 μm long when fully extended), which appears dark at low magnification due to the lilac pigment stripes and the symbiotic green algae. This species often blooms in the pelagial of small lakes and ponds. AZM, adoral zone of membranelles; FV, food vacuoles; MA, macronucleus; PS, pigment stripes; SA, symbiotic green algae.

close

References

Banerjee S, Kelleher JK and Margulis L (1975) The herbicide trifluran is active against microtubule‐based oral morphogenesis in Stentor coeruleus. Cytobios 12: 171–178.

Baroin‐Tourancheau A, Delgado P, Perasso R and Adoutte A (1992) A broad molecular phylogeny of ciliates: identification of major evolutionary trends and radiations within the phylum. Proceedings of the National Academy of Sciences of the USA 89: 9764–9768.

Bennett DA and Francis D (1972) Learning in Stentor. Journal of Protozoology 19: 484–487.

Curds CR, Gates MA and Roberts DMcL (1983) British and other Freshwater Ciliated Protozoa. Part II Ciliophora: Oligohymenophora and Polyhymenophora. Keys and Notes for the Identification of the Free‐Living Genera. Synopsis of the British Fauna (New Series) 23: 1–474.

Foissner W and Wölfl S (1994) Revision of the genus Stentor Oken (Protozoa, Ciliophora) and description of S. araucanus nov. spec. from South American lakes. Journal of Plankton Research 16: 255–289.

Foissner W, Berger H and Kohmann F (1992) Taxonomische und ökologische Revision der Ciliaten des Saprobiensystems – Band II: Peritrichia, Heterotrichida, Odontostomatida. Informationsberichte des Bayerischen Landesamtes für Wasserwirtschaft 5/92: 1–502.

Frankel J (1989) Pattern Formation. Ciliate Studies and Models. Oxford: Oxford University Press.

Harumoto T, Miyake A, Ishikawa N et al. (1998) Chemical defense by means of pigmented extrusomes in the ciliate Blepharisma japonicum. European Journal of Protistology 34: 458–470.

Hemmersbach‐Krause R, Briegleb W, Häder D‐P et al. (1994) Protozoa as model systems for the study of cellular responses to altered gravity conditions. Advances in Space Research 14(8): 49–60.

Hinkle DJ and Wood DC (1994) Is tube‐escape learning by Protozoa associative learning? Behavioral Neuroscience 108: 94–99.

Laybourn‐Parry J, Periss SJ and Seaton GGR (1997) A mixotrophic ciliate as a major contributor to plankton photosynthesis in Australian lakes. Limnology and Oceanography 42: 1463–1467.

Marino MJ and Wood DC (1993) β‐endorphin modulates a mechanoreceptor channel in the protozoan Stentor. Journal of Comparative Physiology A 173: 233–240.

Oken L (1815) Lehrbuch der Naturgeschichte. Dritter Theil. Zoologie Erste Abth. Fleischlose Thiere. Jena: Schmid und Comp. (Stentor, p. 45).

Reisser W (1986) Endosymbiotic associations of freshwater protozoa and algae. Progress in Protistology 1: 195–214.

Tao N, Deforce L, Romanowski M et al. (1994) Stentor and Blepharisma photoreceptors: structure and function. Acta Protozoologica 33: 199–211.

Tartar V (1961) The Biology of Stentor. Oxford: Pergamon Press.

de Terra N (1974) Cortical control of cell division. Science 184: 530–537.

Further Reading

Grain J (1968) Les systèmes fibrillaires chez Stentor igneus Ehrenberg et Spirostomum ambiguum Ehrenberg. Protistologica 4: 27–35.

Grain J (1986) The cytoskeleton in protists: nature, structure, and functions. International Review of Cytology 104: 153–249.

Pelvat B (1985) Observations sur l'ultrastructure de l'appareil buccal chez le cilié hétérotriche Stentor coeruleus. Protistologica 21: 61–80.

Randall JT and Fitton Jackson S (1958) Fine structure and function in Stentor polymorphus. Journal of Biophysical and Biochemical Cytology 4: 807–830.

Tartar V (1970) Transplantation in Protozoa. Transplantation Proceedings 2: 183–190.

Contact Editor close
Submit a note to the editor about this article by filling in the form below.

* Required Field

How to Cite close
Foissner, Wilhelm(Apr 2001) Stentor. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1038/npg.els.0001971]