Condylostoma Bory de St. Vincent, 1824 (ref. ID; 3690) or 1826 (ref. ID; 2014, 4905)
Class Polyhymenophora: Subclass Spirotricha: Order Heterotrichida: Suborder Heterotrichina (ref. ID; 2014)
Class Polyhymenophora Jankowski, 1967: Subclass Spirotricha Butschli, 1889: Order Heterotrichida Stein, 1859: Suborder Heterotrichina Stein, 1859: Family Condylostomatidae Kahl in Doflein & Reichenow, 1929 (ref. ID; 4798)

See Linostomella

[ref. ID; 2014]
Body approximately ovoid (marine species tend to be elongate). The anterior end truncated and carrying conspicuous AZM on the left and a large undulating membrane on the right of an unciliated, wide V-shaped peristome. The body uniformly ciliated and some species are reported to have a few cirri in the anterior region on the right of the membrane. However, when present these cirri are usually difficult to observe without staining procedures. Commonly a single terminal contractile vacuole with forward leading serving canals. Some species have several contractile vacuoles. The macronucleus is moniliform. Most easily confused with Bryometopus which has an oval peristomial field and a small undulating membrane while Condylostoma has a triangular peristome and a large undulating membrane.
Quote; Colin R. Curds, Michael A. Gates and David McL. Roberts "British and other freshwater ciliated protozoa Part II Ciliophora: Oligohymenophora and Polyhymenophora" Cambridge University Press, 1983 (ref. ID; 2014)

Condylostoma circumpedatum Meunier, 1907 (ref. ID; 3540)
Description; Marine form. (ref. ID; 3540)
Condylostoma magnum Spiegel, 1926 (ref. ID; 1621, 4905) reported year? (ref. ID; 3916) reported author and year? (ref. ID; 191, 3292, 3713, 7524)
Redescription; In vivo 450-800 x 80-120 um, elongate and worm-like; cell highly contractile and flexible; dorsoventrally slightly flattened, right and left margins almost parallel in most cell part when fully extended. Posteriorly more or less tapering. Anterior portion conspicuously flattened and usually widely stretched forming a roomly buccal cavity which is large, triangular-shaped, about 1/3 to 1/4 of both length. Contractile vacuole not observed (very likely not present). Pellicle thin, cortical granules ellipsoid, about 1 um in size, irregularly arranged between kineties, which are usually strongly impregnated by protargol. Cytoplasm colourless to greyish (sometimes slightly yellow-brownish when contains many food vacuoles full of diatoms) with numerous tiny lipid droplets. Feeds on ciliates (scuticociliates, small oligotrichs), flagellates and diatoms. Macronucleus beaded, located right of cell margin, anterior end extending mostly over posterior tip of adoral zone. Movement moderately fast gliding on substrate, sensitive to stirring. Adoral zone of membranelles (AZM) dominant, up to 2/5 cell length when contracted, proximal portion invaginated markedly and twisted within buccal cavity. Bases of membranelles about 20 um with cilia ca. 25-30 um long. Two apical "frontal cirri (FC = apical membranes) frontally on right margin of oral cavity close to distal end of AZM. Undulating membrane (PM) highly developed and very long, probably dikinetid, deeply sunk in oral cavity on right, cilia ca. 40-50 um long. About 50 longitudinal somatic kineties composed of paired basal bodies and both ciliated (cilia ca. 15 um long); most kineties extending over entire length of body, about 3-6 kineties on ventral side terminating near buccal cavity and, not seldom, a few kineties more or less shortened or fragment-like. Kineties of left ventral side arranged evidently closer than on right. (ref. ID; 4905)
Comparison; The identification of Condylostoma-species in many cases is difficult because relatively few taxonomic feature are available in this genus; the body shape and size are usually highly variable and their infraciliature is often unclear. We recognize this species basically because of the following characters which correspond with original description (Spiegel 1926): size and body shape (especially the appearance of buccal field and the posterior end of cell), habitat, number of ciliary rows (= somatic kineties) and the ratio of buccal field:body length, though the number of kineties in our population slightly lower (ca. 30 vs. 40 on ventral side). Compared with the similar Condylostoma arenarium Spiegel, 1926, C. magnum has a longer oral cavity (1/3-1/4 vs. 1/5) and more somatic kineties (ca. 50 vs. ca. 30). Additionally, the former "...wird charakterisiert durch die deutlich zu Cirren verschmolzenen Ventralwp., die 4-5 starken Frontalcirren und die dors. stehenden Gruppen von starren Tastwp., von denen besonders eine nahe dem Hinterende oft auffallend ist..." (after Kahl 1932, not mentioned in the original). So the distinction between both species is clear. Condylostoma magnum differs from another morphologically related species, C. patulum Claparede & Lachmann, 1858 in having much more adoral membranelles (150-200 vs. 60-70) and in its significantly longer buccal field (1/3-1/4 vs. 1/10-1/15 of body length) (Wilbert & Kahan 1981). C. rugosum Kahl, 1932 is a small form (300-350 um) with fine, bar-shaped cortical granules (? called prototrichocysts by Kahl, 1932), shorter buccal field (about 1/4-1/5 of cell length) and the ciliary rows " gedehnten Zustande durch unregelmassige Querfurchen wie zerrissen...", possibly without frontal cirri ("Frontalcirren fehlen scheinbar oder sind doch sehr schwach...", q.v. Kahl 1932). So it is clearly distinct from C. magnum. Tuffrau (1967) described a form under the name of Condylostoma magnum, which has only a single large apical membrane and significantly much fewer somatic kineties (according to his illustrations). We supposed, therefore, it is likely a misidentification. After some authors (Bullington 1940; Dragesco & Dragesco-Kerneis 1986), the number of kineties in their magnum-populations is generally higher (90-100, 72-110 respectively) and the pattern of apical membranes seems to be arranged in a different way (ca. 6-7 small ones closely together arranged in a short row, q.v. Dragesco & Dragesco-Kerneis 1986). We are not sure if it concerns different morphotypes or species, since the structure of apical membrane should be, to our knowledge, a good indication of the species distinction. (ref. ID; 4905)
The ultrastructural study. (ref. ID; 7524)
Condylostoma patens (O. F. Muller, 1786) (ref. ID; 1621) reported year? (ref. ID; 1618) or (O. F. Muller) Dujardin (ref. ID; 3690) reported author and year? (ref. ID; 191, 3540)
Description; In salt water. (ref. ID; 1618)
Measurements; 250-550 um long. (ref. ID; 1618)
Condylostoma patulum Claparede & Lachmann, 1858 (ref. ID; 645, 1621)
Description; C. patulum is ordinarily between 600 and 900 um in length, but in brackish water can reach a length of over 1,300 um (Dragesco, 1963). When there are such wide variations within a single species, species identification is difficult; other diagnostic morphological characteristics are in themselves less informative. The distinguishing characteristics of C. patulum are the small peristome (1/6 to 1/5 the body length) and the rounded hind end. The infraciliature of C. patulum was studied by Dragesco (1963) with the protargol method, so that his population in Roscoff can be compared with that of Solar Lake. Differences are evident in the infraciliature of the ectoplasm lip to the right of the peristome. In the Solar Lake form the kineties here come from the middle and pass without interruption to the right edge of the peristome. Animals from the Roscoff population have a large number of kinety fragments in this position. The Solar Lake form bears as many as 6 cirri on the apical margin of the lip, which are lacking in the Roscoff animals. The structure of the macronucleus is also different. Whereas we observed 15 to 24 spindle- or ribbon-shaped macronuclear elements, Dragesco found only 11. The length of the peristome of the Roscoff form is about 100 um; we found it to be between 45 and 65 um long, but it should be noted particularly that the size of the peristome varies independently of body size. The main difference between the two forms is clearly the possession of cirri on the ectoplasm lip. Borror (1973) regards them as typical of the genus, and this appears to be the case, apart from a few exceptions such as C. vorticella. But because the cirri immediately adjoin the membranelles of the AZM and look exactly like them, they can be recognized only in protargol preparations, by way of their kinetosome pattern. Perhaps Dragesco (1963) overlooked them. Because the remaining characteristics are appropriate to the species patulum, we have presented the Solar Lake form as C. patulum here. The Solar Lake population can be described further as follows: Length 500 to 800 um, kinety number 36 to 42. Most of the animals have 40 kineties, in each of which there are about 15 kinetosome pairs per 10 um. The peristome is 1/10 to 1/15 the length of the body. The AZM comprises 60 to 70 membranelles. The macronucleus has a string-of-beads shape with about 20 elements, some of them spindle-shaped. Contractile vacuole in the front part of the posterior third of the body. The cytoplasm is colored dark by black granules. The body is flexible, but not very contractile. Locomotion is slow and sluggish. (ref. ID; 645)
Condylostoma reichi Wilbert & Kahas, 1981 (ref. ID; 645 original paper)
Description; Condylostoma reichi, with a body length of about 2 mm, is one of the largest of all ciliates, and certainly the largest species of the genus Condylostoma so far known. The body shape resembles that of a tadpole. The head-like enlargement at the anterior end contains the massive peristome, almost a quarter as long as the body. The body is flattened ventrally; the back arches outward, with a keel from the anterior third to behind the middle of the body. The animal is very flexible, and can contract to about three-quarters of its resting length. It moves with a slow, sluggish crawl. The cytoplasm is colorless but contains many black granules that give the animal a gray to black appearance. A large contractile vacuole lies in the posterior third, and there is a terminal fecal vacuole. In the middle of the body, at intervals of about 5 um, there are between 55 and 69 kineties. Their number decreases posteriorly, with only a few at the hind end. The cilia are ca. 8 um long. The macronucleus is shaped like a string of beads. The peristome field is bounded anteriorly and along its left side by the adoral membranelle zone (AZM). This consists of 190 to 220 membranelles and ends posteriorly, after two spiral turns, in a pharyngeal funnel. The undulating membrane is on the right side of the peristome. Its base is covered by a lip of ectoplasm that juts out on the left. Anteriorly, where the ectoplasm lip abuts against the AZM, stands a longitudinal row of up to 11 cirri. (ref. ID; 645)
Etymology; Dedicated to K. Reich, Professor of Protozoology at the Hebrew University of Jerusalem (Israel). (ref. ID; 645)
Condylostoma terricola Foissner, 1995 (ref. ID; 4613, 4861 original paper)
Diagnosis; In vivo 90-140 x 30-60 um. Cortical granules conspicuously bright, yellowish, 0.7 x 0.5 um in size, arranged in loose rows with small clusters interspersed. On average 7 macronuclear beads, 17 somatic kineties and 36 adoral membranelles. (ref. ID; 4861)
Description; Narrowly to broadly sac-shaped, oral portion often distinctly widened and slightly contractile, posterior end invariably broadly rounded. Very flexible, oral area distinctly flattened. Macronucleus moniliform, along dorsal side of cell, beads connected by rather broad bridges; nucleoli variable, in some specimens tiny, in others rather large. Micronuclei not observed, do not impregnate with the protargol method used. Contractile vacuole at posterior end. Cortex thick, gelatinous. Cells appear greyish at low magnification because colour of cortical granules is very light. Cytoplasm strongly vacuolated due to many large, almost empty vacuoles. Feeds on fungal spores, heterotrophic flagellates (Peranema sp.) ciliates (hypotrichs, Sathrophilus muscorum) and even on brownish soil particles. Swims slowly, often crawling around soil particles. Somatic and oral infraciliature as in other members of genus. Right of kineties distinct (postciliary) fibre recognizable also in live specimens. Basal bodies paired throughout. Adoral organelles each composed of 2 long rows and 1 short row of basal bodies. Paroral membrane conspicuous, cilia 30 um (!) long, at right anterior end 3-4 more or less distinctly separated cirri forming conspicuous tuft. Buccal cavity large, deep, underlain by thick fibres. Pharynx and pharyngeal fibres indistinct. (ref. ID; 4861)
Comparison with related species; This is the first reliable record of a Condylostoma species in soil. Most members of this genus live in marine biotopes and have a distinct tail. Five species are known from saline inland waters or from freshwater: Condylostoma tardum Penard 1922 is larger (> 180 um) than C. terricola and has only 3 macronuclear beads (Faure-Fremiet 1958, Kahl 1932, Penard 1922); C. nigra Dragesco, 1960 is also larger (180-300 um) than C. terricola and has blue cortical granules (like Stentor coeruleus), 40 somatic kineties and several contractile vacuoles along the dorsal and ventral side; C. vorax Villeneuve-Brachon, 1940 is poorly described, but is distinctly larger (250-400 um) than C. terricola, has 30-40 somatic kineties and apparently lacks coloured cortical granules; C. kasymovi Alekperov, 1984 is also poorly described (according to silver nitrate impregnated cells only), but is distinctly larger (240-280 um) than C. terricola and has 65-70 somatic kineties, 70-75 adoral membranelles, and 15-17 macronuclear beads; C. luteum Kahl, 1932 is a sapropelic species whose shape, size and cortical granulation are very similar to those of C. terricola. It has, however, only 2 macronuclear beads, curious rods (extrusomes?) around the pharynx, and a different arrangement of the cortical granules, which form short, transverse rows. (ref. ID; 4861)
Derivatio nominis; "terricola" refers to the occurrence in soil. (ref. ID; 4861)
Type locality; Upper soil layer near the ranch house "La Casona" in the Santa Rosa National Park, Costa Rica, W 85 degrees 38', N 10 degrees 50'. (ref. ID; 4861)
Type specimens deposited; Slides with type and voucher specimens have been deposited in the Oberosterreichische Landesmuseum in Linz (LI), Austria. Relevant specimens are marked by a black ink circle on the cover glass. (ref. ID; 4861)
Condylostoma vorticella (Ehrenberg, 1833) (ref. ID; 1621, 2245, 4488) or 1838 (ref. ID; 4798) reported year? (ref. ID; 1219, 1618, 5462, 7094)
Syn; Condylostoma stagnale Wrzesniowski, 1870 (ref. ID; 1621)
Description; In fresh water. (ref. ID; 1618)
Measurements; 100-200 um long. (ref. ID; 1618)