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The World of Protozoa, Rotifera, Nematoda and Oligochaeta


Ciliophrys Cienkowski, 1875 (ref. ID; 3960) or Cienkowsky, 1875 (ref. ID; 6733)

[ref. ID; 1618]
Spherical with extremely fine radiating filopodia, giving the appearance of a typical heliozoan, with a single flagellum which is difficult to distinguish from the numerous filopodia, but which becomes conspicuous when the pseudopodia are withdrawn; fresh or salt water. (ref. ID; 1618)

[ref. ID; 3960]
Ciliophrys possess a single flagellum that acts as a tractellum, and hence all species' flagella must possess tubular mastigonemes. (ref. ID; 3960)
  1. Ciliophrys infusionum Cienkowski (ref. ID; 1618)
  2. Ciliophrys marina Caullery, 1909 (ref. ID; 3960) reported year? (ref. ID; 1618, 5624) or Gaullery (ref. ID; 3497)
    Syn; Dimorpha floridanis Bovee, 1960 (ref. ID; 3960); Dimorpha monomastix Penard, 1921 (ref. ID; 3960)

Ciliophrys infusionum Cienkowski (ref. ID; 1618)


In freshwater infusion. (ref. ID; 1618)


25-30 um long. (ref. ID; 1618)

Ciliophrys marina Caullery, 1909 (ref. ID; 3960) reported year? (ref. ID; 1618, 5624) or Gaullery (ref. ID; 3497)


Dimorpha floridanis Bovee, 1960 (ref. ID; 3960); Dimorpha monomastix Penard, 1921 (ref. ID; 3960)


In salt water. (ref. ID; 1618)
The small delicate form has fine axopodia, a large nucleus with a definite karyosome and many small contractile vacuoles scattering all over the cell. In general, it increases by binary division and makes a colony composed of a number of cells in still water: colonies sometimes enlarge over 100 cells in the laboratory. While flagellate daughter cells germinate in some cases. The flagellated daughter organism in the early stage is fusiform, and provided with a single organism in the early stage in fusiform, and provided with a single flagellum as long as it and a large nucleus at the anterior region. The fusiform flagellate specimens seem to increase by division as well as mother cells with radial axopodia. The fusiform daughter cell produces fewer pointing pseudopodia from the posterior part in an early stage and at last, many from the entire surface. Contractile vacuoles increase according to change of a form, and the nucleus moves from the anterior end to the center of the spherical body, of which slender radial pseudopodia are gradually transformed to fine long axopodia. The bodies of well-developed specimens without flagella are more or less smaller than those of in mature individuals carrying radial pseudopodia. (ref. ID; 3497)
In the heliozoan form, both axopodia and a very slow-beating flagellum are present. The spherical cell body measures 10-20 um in diameter, the flagellum 15-20 um in length; and the axopodia are ca. 0.1 um in diameter and up to 50 um long. The number of axopodia varies with the size and physiological state of the organism, and larger cells consistently have more axopodia that the smaller ones. In all cases the axopodia are arranged about the cell in near spherical symmetry. In the slow-beating, or quiescent state, the flagellum is held close to the cell body in a very characteristic figure-eight wave form, with approximately 1.5 complete waves passing basifugally along the flagellum at a rate of only 2 or 3/min. The circular flagellar arcs of the quiescent flagellum each enclose nearly a full 360 degrees and each arc has a diameter of ca. 2.5 um. When the flagellum is broken from the cell by physical agitation, it immediately ceases movement but retains its characteristic shape. The rate of re-growth of a new flagellum, in two cases in which it was observed in detail, was ca. 1 um/min. During re-growth, when the 2-3 um long flagellum, is first recognized, it is already beating. If the cell transforms to the swimming state during the period of flagellar re-growth, a 5-um long flagellum will pull the cell through the water at a rate of ca. 10 um/sec. The axopodia have refractile granules, termed muciferous bodies, distributed along their length, but, in contrast to other heliozoa, these granules are regularly spaced and show very limited bidirectional streaming, except when the organism is actively capturing food organisms. The details of ultrastructure and membrane attachments of the muciferous bodies of Ciliophrys have been described previously (Davidson 1973). The central nucleus, with a diameter of 3 um and a central dense nucleolus, is difficult to discern in living cells unless they are flattened beneath a cover slip. By light microscopy the nucleus and nucleolus together superficially resemble the centroplast of the centrohelidan heliozoa, and this has probably led to some of the confusion about the presence or absence of a centroplast in several of the helioflagellate species. The axopodia contract in response to a mechanical shock in less than 20 msec. A similar swift axopodial contraction occurs in Heterophrys marina and in Actinophrys sol and is much more rapid than, and quite distinct from, the axopodial absorption that occurs during transformation to the swimming form. Following contraction, the axopodia take 2-3 min to re-extend; the first 30-45 sec of which form a refractory period during which further mechanical shocks will not elicit a contraction. The re-extension rate during the first portion of the re-extension period average ca. 10 um/sec. In response to physical agitation, such as vigorous shaking, many of the cells slowly absorb their axopodia and transform into actively swimming flagellates. No other environmental variable, including changes of osmotic pressure, temperature, or ionic composition of the medium, was found which produced any appreciable increase in the number of transformations above that resulting from the attendant physical disturbance. Osmotic change has been described by Bovee (1960) as producing transformation of a fresh water helioflagellate. Transformation often occurs spontaneously on the microscope slide, and the following description is a synthesis of a number of such observations. Bovee (1960) has given a very similar description of transformation of a helioflagellate which he named Dimorpha floridanis but which is more probably a species of Ciliophrys. During transformation the axopodia shorten, meld together, and fold away from the flagellum. The single anterior flagellum, which before transformation was held close against the body in the very slow beating, figure-eight shape, slowly begins to increase its rate of beating and simultaneously to decrease the angle of arc enclosed by each bend from ca. 360 degrees to 180 degrees so that it comes to resemble a sine wave curve. The number of arcs present on each flagellum stays about the same, however, so that now each of the three arcs is connected by a straight region. As the axopodia are absorbed, the cell body lengthens along an axis passing through the flagellar base and suddenly, as if in response to some sort of abrupt physiological change, the flagellum is pulled toward the body once or twice and is then immediately re-extended at the typical rapid swimming frequency (70-100 Hz). Simultaneously the flagellar arcs decrease to much less than 180 degrees and the number of arcs along the flagellum increases to ca. 3.5 or 4. As transformation proceeds, the axopodia decrease in size, and their remnants all point posteriorly to form a kind of tail. Since the substrate attachment is dependent on the axopodia, it weakens as the axopodia are retracted until finally the cell breaks loose and swims away. The complete transformation can take as little as 30 sec. For a period after transformation the swimming cell often has a distinctive dumbbell shape. This apparently caused by a posterior mass of depolymerized axonemal materials. The fully transformed cell is teardrop-shaped, pointed posteriorly and blunt anteriorly. The nucleus is sometimes visible immediately behind the flagellum. No feeding by swimming cells has been observed. Micrographs of swimming cell taken with stroboscopic illumination show that the flagellar waves of the activated flagellum are planar and, like those of the quiescent flagellum, are made up of circular arcs connected by straight lines. Under standard incandescent illumination the active flagellum presents a very interesting optical illusion. Due to the shallow wave arcs and the rapidity of the beat, which is above the frequency at which the eye can detect individual events, only the outlines of the limit of the waveform can be seen, so that the flagellum appears to be held straight and rigid and simply to be swung rapidly from side to side like a pendulum. This phenomenon has been diagrammed by Throndsen (1971), and is a general characteristic of the chrysomonad form of tractellar locomotion. Small changes of swimming direction are accomplished by an angular shift in the direction of the flagellar beat, although major changes of direction are accomplished by the avoiding or shock reaction described below. The flagellum has a double row of the chrysomonad form of tubular mastigonemes, described in more detail later, and these cause the flagellum to act like Ochromonas's tractellum; that is, the flagellum is held forward and flagellar waves pass from base to tip while the water flows toward the cell. In a 10 centipoise methyl cellulose solution, however, the medium moves in the same direction as the flagellar waves so that the cell is pushed by the flagellum. The organism cannot swim under these conditions, since the body is not held rigid enough relative to the flagellum and instead swings lateral to the axis of the flagellar beat, and very frequent avoiding reactions occur. Swimming cells move very rapidly, up to 150 um/sec, and usually travel in slightly curved paths. When a swimming cell or its leading flagellum strikes a piece of debris, a very characteristic avoiding reaction occurs during which the flagellum is retracted toward the body, whipped vigorously about several times, and then is re-extended. Usually this results in a change in the swimming direction, and the reaction is repeated until the obstacle is cleared. The same reaction can be elicited by a mechanical shock and frequently occurs spontaneously during swimming, so that the cell rarely swims for more than 5-10 sec without changing direction. The flagellar retraction during the avoiding reaction is accomplished by an increase in the angle of the flagellar arcs to about that of the inactive flagellum but without the associated decrease in the frequency to that of the inactive flagellum. In artificial seawater with a low calcium ion concentration (2 mM or less) transformation to the swimming state still occurs normally, but the avoiding reaction is completely inhibited. Under low calcium conditions the flagellum operates in only two modes, the completely activated, and the slow-beating (quiescent). When an obstacle is encountered by an actively swimming cell in media of low calcium ion concentration, the cell continues to swim against the obstacle until it either assumes its heliozoan form, or it clears the obstacle by chance. In high potassium ion concentration (100 mM or greater), the avoiding reaction is similarly inhibited. Transformation from the swimming form back to the heliozoan form also occurs in both normal and in low-calcium seawater, and the process is essentially the reverse of the transformation from the heliozoan to the swimming form. The flagellum slows down and reforms the inactive figure-eight configuration as the axopodia re-form. Axopodial re-extension takes from one to several minutes to occur and follows a time course very similar to the re-extension following depolymerization induced by exposure to a short period of cold (4 degrees C for 15 min or less). No instances of the explosively rapid re-extension reported by Bovee (1960) in Dimorpha floridanis or by Penard (1921) in a species of Ciliophrys have been observed. Two or more cells often fuse together while in the heliozoan form to form a multinucleate syncytium, particularly when they are brought into contact by centrifugation but also quite often under normal conditions. When only one cell of a syncytial mass transforms, it is capable of pulling the whole mass slowly about as it swims. When two cells of a fused mass are actively swimming at the same time, they always go through simultaneous avoiding reactions, whether the avoiding reactions are induced by a mechanical shock or occur spontaneously. (ref. ID; 3960)


Penard (1921) described what he thought was a marine species of Dimorpha with a single flagellum which he named Dimorpha monomastix. He observed only living cells and stated that he was unable to see the central granule or centroplast, and he then went on do describe and draw a centrally located nucleus. He also gave an excellent description of the transformation process and swimming behavior of this organisms, and in every respect his observations coincide with my observations on C. marina. He found that in the heliozoan state the flagellum was held against the body in a figure-eight shaped curve with waves slowly passing from the base to the tip and then, when activated during transformation, the flagellum was extended anteriorly for swimming. The only difference between Penard's description and mine is in the speed of transformation, which Penard said can occur in as little as two seconds, while in my species it takes several sends to occur. In short, it appears that Penard's Dimorpha monomastix is actually synonymous with C. marina. A similar misidentification may have been made by Bovee (1960) when he described the species Dimorpha floridanis. He, too, observed only living cells, and he described the axonemes as arising from a central granule, 2.25 um in diameter, with a dense core 1.5 um in diameter, This central granule is much larger than the centroplast described either in Dimorpha or in the centrohelidan heliozoa, and closely resembles the central nucleus in C. marina. The organisms Bovee described had two flagella, unlike other Ciliophrys or Actinomonas species, but from his rather limited description of its mode of swimming it would appear that one was held anteriorly and acted as a tractellum while the other trailed posteriorly. Such a swimming behavior would indicate a typical chrysomonad type of heterokont flagellation with tubular mastigonemes along the anteriorly flagellum. Several of Bovee's observations, such as the invariant number of axopodia, should be confirmed. The species badly needs to be re-collected and re-described. His observations on the very rapid speed of axopodial re-extension coincide with those of Penard for "Dimorpha monomastix", which, as noted above, is actually another Ciliophrys species. Bovee described the axopodia as sometimes spearing what he considered to be peripheral nucleus but which could well have been simply a vesicle of some sort. (ref. ID; 3960)


About 10 um in diameter. (ref. ID; 1618)
Diameter without axopodia 5-25 um; length of a flagellate daughter organism 17-30 um. (ref. ID; 3497)