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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Woodruffia

Woodruffia Kahl, 1931 (ref. ID; 2013, 7706)

Class Kinetofragminophora: Subclass Vestibulifera: Order Colpodida (ref. ID; 2013)
Suborder Cyrtolophosidina Foissner, 1978: Family Woodruffiidae Gelei, 1954 (ref. ID; 7706)

[ref. ID; 2013]
Body elongate reniform to pyriform, sometimes with very short anterior rostrum, may be dorso-ventrally flattened. Highly variable in size (80-400 um long). Body entirely covered with cilia, uniformly and symmetrically arranged in oblique rows. Cilia often arise in pairs. The vestibular opening may either be slit-like or oval in the anterior region of the cell. On the right of the oral aperture there is a C-shaped row of paired cilia (paroral ciliature) and many short double rows of cilia on the left (adoral ciliary membranelle) which may extend forwards slightly. Macronucleus large and oval with a single micronucleus contained within the macronuclear membrane. Single contractile vacuole terminal. Division takes place within a thin-walled cyst producing 2 to 4 daughters. Resistant cysts with thick walls may also be formed. Most easily confused with Platyophrya which has a reduction of cilia on the left side and hence is unsymmetrical.
Quote; Colin R. Curds "British and other freshwater ciliated protozoa Part I Ciliophora: Kinetofragminophora" Cambridge University Press, 1982 (ref. ID; 2013)

[ref. ID; 3855]
It is difficult at present to resolve relationships among species in the genus Woodruffia, since oral structure among the species is apparently quite variable. Prelle (1963) described 2 types of oral architecture in the genus: the rostrata type, represented by Woodruffia rostrata Kahl, 1931 and including Woodruffia lichenicola Gellert, 1955, in which these are several kineties aligned at right angles along the right side of the oral region; the metabolica type, represented by W. metabolica Johnson & Larson, 1930 and including Woodruffia sinistromembranellata Gellert, 1955, in which there is a single paroral parallel to the right (and posterior) border of the oral region. A 3rd type now exists; the sporophaga type, is represented by Woodruffia sporophaga Beers & Sherwood, 1966, in which there are 2 parorals parallel to the posterior (and right) border of the oral region. A synonymy of the genus Woodruffia Kahl, 1931 with the genus Platyophrya Kahl, 1926 has been suggested recently by Groliere (1975) and supported by Buitkamp (1977). Dragesco et al. (1977) suggest transferring W. sinistromembranellata and W. lichenicola to the genus Platyophrya but favor retaining W. metabolica in a distinct genus; their reasons are not clear. De Puytorac et al. (1979) distinguish the Woodruffiidae, which includes Woodruffia Kahl (1930, 1931), Kuklikophrya Njine (1979), and Rostrophrya Njine, in de Puytorac et al. (1979), from the Platyophryidae, which includes Platyophrya Kahl, by the disorganization of the paroral during stomatogenesis. There is no such disorganization in Platyophyra. A detailed description of trophont structure and stomatogensis in several other genera and species would aid in resolving this taxonomic problem. (ref. ID; 3855)
  1. Woodruffia lichenicola Gellert, 1955 (ref. ID; 3855)
  2. Woodruffia metabolica Johnson & Larson, 1930 (ref. ID; 3855) or 1938 (ref. ID; 1308, 1618, 7537) reported author and year? (ref. ID; 191)
  3. Woodruffia rostrata Kahl, 1931 (ref. ID; 4855) reported year? (ref. ID; 1618, 1622)
  4. Woodruffia sinistromembranellata Gellert, 1955 (ref. ID; 3855)
  5. Woodruffia sporophaga Beers & Sherwood, 1966 (ref. ID; 3855)

Woodruffia metabolica Johnson & Larson, 1930 (ref. ID; 3855) or 1938 (ref. ID; 1308, 1618, 7537) reported author and year? (ref. ID; 191)

Descriptions

Pyriform; in fresh water ponds. Johnson and Evans find two types of protective cysts in this ciliate: "stable" and "unstable" cysts, formation of both of which depends upon the absence of food. These cysts have three membranes: a thin inner-most endocyst, a rigid mesocyst and a gelatinous outer ectocysts. The protoplasmic mass of the stable cyst is smaller, and free from vacuoles, and its ectocyst is thick, while that of the unstable cyst is larger, contains at least one fluid vacuole and its ectocyst is very thin. Crowing, feeding on starved Paramecium, increasing the temperature, and increasing the salt concentration of the medium, are said to influence the formation of unstable cysts. The two authors further reported that when free-swimming individuals were subjected, in the absence of food, to extremes of temperature, high concentrations of hydrogen-ion, and low oxygen tension, unstable cysts were formed; when the oxygen tension decreased, the tendency to encyst increased, even when ample food was present. The unstable cysts are said to remain viable for six months. Excystment is induced by changing the balanced salt solution, by replacing it with distilled water and by lowering temperature from 30 to 20 degrees C. (ref. ID; 1618)
Woodruffia metabolica, a large, free-swimming ciliate, is an obligate predator of Paramecium. Trophi forms vary in length from 154 um to over 400 um. The uniformly ciliated body is flattened ventrally and slightly convex dorsally. The somatic kineties originate at the slit-like oral cavity and course posteriad to converge near the posterior pole. Kineties of the right side form an oblique angle adjacent to the oral cavity slit; those of the left side are almost perpendicular near their origin. The kineties are predominantly bipolar, although interdigitated kineties are often observed. The oral cavity is a long crescentic groove in the anterior ventral third of the body. Usually the groove is tightly closed, but opens to ingest Paramecium. Bordering the right side of the oral cavity and extending along its entire length is a paroral membrane. It is composed of 2 rows of cilia: the inner row bends over sharply, immediately after its emergence and comes to lie against the right wall of the oral cavity; the outer lateral row of cilia is erect and undulatory. A series of small polykinetids of 4 or 5 associated cilia borders the left side of the oral cavity. The length of the oral area is equal to ~1/3 of the body length. Because of the ciliate's variation in size, the number of polykinetids, 1.5 um apart, ranges ~35-90, creating an extensive, distinct "adoral zone of membranelles". When the cytostome opens, its right and left halves appear as large membranous sheets. (ref. ID; 3855)

Measurements

85-400 um long; division cysts 85-155 um in diameter; resting cysts 40-62 um in diameter. (ref. ID; 1618)

Woodruffia rostrata Kahl, 1931 (ref. ID; 4855) reported year? (ref. ID; 1618, 1622)

Descriptions

Salt water culture with Oscillatoria. (ref. ID; 1618)

Measurements

120-180 um long. (ref. ID; 1618)