The World of Protozoa, Rotifera, Nematoda and Oligochaeta
Trichocerca
Trichocerca Lamarck, 1801 (ref. ID; 7815)
Class Monogonontaet: Order Ploimida: Family Trichocercidae (ref. ID; 6806)
Synonym Acanthodactylus Tessin, 1890 (ref. ID; 3688); Coelopus Gosse, 1886 (ref. ID; 3514, 3688); Diurella Bory de St. Vincent, 1824 (ref. ID; 3514, 3688); Mastigocerca Ehrenberg, 1830 (ref. ID; 2978, 3688); Monocerca Bory de St. Vincent, 1826 (ref. ID; 2978, 3688); Rattulus Lamarck, 1816 (ref. ID; 2978, 3514, 3688); Vaginaria Schrank, 1802 (ref. ID; 3688)
ref. ID; 1663
Lorica a single cylindrical piece, often with teeth and longitudinal grooves or ridges. Body cylindrical, more or less curved, and asymmetrical. Toes spine-like, of unequal length, and with several small spinules at their base. Creeping or free-swimming movement. Mastax virgate. Trophi asymmetrical. (ref. ID; 1663)
ref. ID; 1923
Most of genus are common in lake plankton. Length of the lorica 100-500 µm. The genus includes formerly in Diurella (Edmondson, 1935), which included species with equal toes and those in which the short toe was more than 1/3 the length of the other. Trichocerca, as presently defined, is a heterogenous genus, and possibly should be split, but not on the basis of toe length. (ref. ID; 1923)
ref. ID; 2760
The situation of Trichocerca Lamarck and Diurella Bory de Saint Vincent; There is a perfect transition from one group to the other by reduction of the right toe. Jennings (1903) separates the groups by a single character; that is, whether the right toe is more or less than one third the length of the left. Such a distinction is, of course, very artificial, and so very objectionable. In text figure 1 of his monograph, Jennings illustrates beautifully the transition from one group to the other without seeming to realize the significance of his figure. Following the rules as above, it is proposed to unite these two groups into Trichocerca Lamarck, type species, T. rattus (Muller). As far as can be determined, the only homonyms in the genus as here understood are T. stylata (Gosse) and stylata (Eyferth). Since Eyferth's name is the later one, it must be abandoned and the earliest synonym which does not conflict with any other Trichocerca must be used. Therefore, Trichocerca similis Wierzejski is to be used rather than T. stylata (Eyferth) (= Diurella stylata Eyferth). (ref. ID; 2760)
ref. ID; 3114
This genus formerly consisted of two genera, Diurella Bory de St. Vincent, 1824 and Trichocerca Lamark, 1801. However, recently Edmondson (1935) found some intermediate specimens between both genera and insisted that it is quite impossible to separate Diurella from Trichocerca. This consideration was made on the basis of the female, but generally acceptable (cf. Voigt, who nevertheless, divided this genus into two groups). The male of the old genus Diurella was observed by Wiszniewski (1934) and Sudzuki (1955). According to Sudzuki, the male of Diurella too is closely allied to that of Trichocerca. Consequently, we should not separate, on the generic level at least, Diurella from Trichocerca. Nevertheless, as will be mentioned later, Sudzuki could divide them into three groups, which are comparable from another view point to genera. The males of Trichocerca have been observed exclusively by two authors, namely 4 species by Wesenberg-Lund (1923) and 8 by Sudzuki (1958) respectively, but there are some disagreements between both authors. The number of the species and the individuals observed by the latter author is, however, much greater than that of the former. Therefore, even though any differences existed between them, if some characters were available for all the latter specimens, the present author would like to consider that those characters would represent genus Trichocerca. Thus, we had to amend some character as follows: The male of Trichocerca is: 1. clearly provided with a motile foot and never 'no foot (Wesenberg-Lund 1923)'. 2. penis with a ciliary wreath and not 'a chitinous plate (W-L)'. 3. dorsal antenna with a long sensory seta, instead of 'soft hairs (W-L)'. Further, Sudzuki (1957) considered that the males of Trichocerca pediculus, T. pygocerca and T. cylindrica are markedly different in the general form from those of the common species of Trichocerca. Thus we could divide genus Trichocerca into three groups as follows, if we use only the characters of the male: 1. Group I: body highly reduced, 55-70 µm in total length, conical in shape, weakly loricate, large oil drop at the middle to the dorsal side. One red cerebral eye. A foot highly obliterated without toes, and unretractile. No real penis. At a glance this male resembles that of Gastropodinae and Polyarthrinae. Here belong most Trichocerca species including species of the old genus Diurella. 2. Group II: body 74-92 µm long in total, conical in shape, hardly loricated, wheel organ very like the female. Three antennae developed. No eye spots present. No foot. Penis large, provided with two joints. At a glance, this male resembles that of Keratellidae or Synchaetidae. Here belongs species Trichocerca taurocephala (cf. Wiszniewski 1936), Trichocerca cylindrica (Sudzuki 1956, p.419-421). 3. Group III: body illoricate and elongated, and constricted off from the body proper. One cerebral eye. Dorsal antenna present. Foot with 3-4 joints. One long toe, gonopore opening between 3-4th with 3-4 segment. No oil drops are found. This male resembles that to Monostyla psammophila and Encentrum velox (cf. Wiszniewksi 1934). To this group belong such psammon species as T. pediculus. T. pygocerca (cf. Ruttner-Kolisko 1956, s.39). These facts may suggest that the subfamily Trichocercinae has a close relation with the so-called Notommatid rotifers in the conception of Wesenberg-Lund, and that the difference between any two groups of them might correspond to a generic separation. Especially, the male of group III, is quite different from other groups of Trichocerca. Considering that usually allied females have allied males, if any two females are closely related to one another, the males should also closely resemble each other in his features. However, in the genus Trichocerca at least tree types of the male can be distinguished, even though the females resembles one another. T. cylindrica is much adapted to the limnetic life; this species carries its egg by means of a thread in contrast to all other species of the genus. This is reminiscent of the relation between Notholca and the species longispina which is now placed in a separate genus. This treatment is regarded to be correct by all rotifer specialists. We might also establish a new distinct genus for T. cylindrica and others, but unfortunately, Sudzuki has not yet seen the male belonging to the type III, about which he therefore can say nothing but cite Ruttner-Kolisko (1955). Sudzuki would like to propose to establish the following new genera under the subfamily Trichocercinae. Genus Trichocerca: species for the group I. Genus Paratrichocerca: species for the group II. Genus Diurellaeopsis: species for the group III. (ref. ID; 3114)
ref. ID; 3334
The members of this genus all very asymmetrical. The trunk is usually cylindrical and is often arched. The foot is short and ends in one or two toes. If there are two toes, then they are usually of unequal length, with the left longer than the right. The mastax has virgate trophi that are also asymmetrical. (ref. ID; 3334)
ref. ID; 4592
Body cylindrical, more or less curved, and asymmetrical. Lorica a single cylindrical piece, often with teeth and longitudinal grooves or ridges. Toes spine-like, of unequal length, often with several spinules at their base. Mastax rod-like. (ref. ID; 4592)
Lorica relatively stiff. Body elongate, slightly curved. Margins of head aperture ventrally with a broad-based, triangular projection, left-lateral side with a shallow median projection anterior of a short striped field, right lateral side with inconspicuous trapezoidal striped field ventrally. A shallow subdorsal keel on left side of body in anterior third, an elongate striped field subdorsally on right side, reaching up to medially. Foot short, terminal. Toes subdistally, held ventrally. Toes spiniform, curved proximally and distally, the right one about half as long as the left one. Each of these with two substyli of different shape and length near their basis. Openings of lateral antennae in distal part of body, the left more distally than the right. Eye present. Trophi asymmetrical. Fulcrum elongate, with median antero-ventral crest and terminal basal plate. Left ramus with large, outwards directed alulus. Suprauncus with rows of long, inwards-curved teeth anteriorly on the ventral side, and a antero-lateral spine. Supraramus present. Left uncus with single basal part, and fan-shaped distal part consisting of 3-4 fused teeth. Left manubrium elongate, widened proximally, distally with simple crutch. Right ramus smaller than left, with straight alulus. Suprauncus with antero-median row of short, fused teeth and rounded antero-lateral projection. Supraramus present. Right uncus and manubrium strongly reduced. (ref. ID; 3004)
Male: Male unknown. (ref. ID; 3004)
Comments
Trichocerca abilioi n. sp. belongs to a group of elongate. Trichocerca with subequal toes, such as T. tigris (O.F. Muller), T. myersi (Hauer), T. scipio (Gosse), T. vargai Wulfert or T. kostei Segers. The disposition of the projections of the head aperture, with its conspicuous triangular ventral projection, and the shape of its trophi easily distinguish the species. The external morphology of the Nigerian specimens is identical to that of the Brazilian material, their trophi have more acutely pointed rami but are otherwise highly similar. (ref. ID; 3004)
Etymology
The species is named after Abilio Lopez de Oliveiro-Neto, who originally collected and recognised the species as new. (ref. ID; 3004)
Type locality
Temporary lagoon along rio Branca, about 5 km S. of Boa Vista, Roraima, Brasil, 24 June 1987. Conductivity 5.7 uS; O2 7.2 mg/l; temperature (surface) 32.9 degrees C; pH 6.1. (ref. ID; 3004)
Measurements
Body length 162-209 (198), height 39-54 (49); foot length 10-16 (16); trophi length 55-60 (57); right toe length 26-44 (42); left toe length 44-62 (broken) (measurements on Nigerian specimen between brackets); fulcrum length 43-45; left manubrium length 40; left ramus length (incl. alulus) 22-26; right ramus length (incl. alulus) 20-22 µm. (ref. ID; 3004)
The body is long. The main toe is more than half the length of the body. The keel on the body extends for more than half the body length. Trophi large, the right manubrium larger than the left. This species resembles T. braziliensis. (ref. ID; 2715)
Donner (1950) has described this species in detail of material from Southern Moravia. The Ontario specimens seem to have a maximum width slightly greater than those described by Donner (1950) and the body is shorter. The left toe is as long as the body and has eight or nine substyles surrounding it. The trophi are dignostic. The wide allulae on the rami shown by Donner's drawing (1950) were visible as very thin plates, but in most cases the outline could not be clearly distinguished. (ref. ID; 5936)
Measurements
Length of body 225; main toe 150; width 69 µm. (ref. ID; 2715)
Lorica length 180; toe 175 µm. (ref. ID; 4606)
Length of body 238-271; maximum width 71; left toe 230-241; length of trophi 65; fulcrum 49; left manubrium 49; right manubrium 38 µm. (ref. ID; 5936)
Examination of specimens confirms the views of Edmondson (1938) that T. bidens is not a synonym for D. cavia Gosse. The anterior projections are true spines and not folds. (ref. ID; 3126)
Measurements
Length of body 105; toes 34 and 21 µm. (ref. ID; 3126)
Length of body 110; length of toes 30 µm. (ref. ID; 3521)
Body slender, conical, cuticula very thin. Frontal spines long, thin, slightly curved emerging from a broad basis. Dorsal keel broad, faintly strippled, reaching down to two-thirds of the body. Foot with one joint only, toes short, unequal, crossed. Internal organization normal, big red eyespot on the dorsal side of the ganglion below the neck-line. Trophi asymmetrical, different from the picture shown in Voigt, 1957. Left manubrium sturdy, with a hook and eyelet. Right manubrium thin, nearly the same length, with a hook. Fulcrum short, thin, unci broad, multidentate. According to Pejler (1965) T. birostris is an indicator or eutrophy. (ref. ID; 2894)
Measurements
Length 170-175; toes 22 and 16; frontal spines 35-40 µm. This is much smaller than given by Voigt and approaching T. similis, a very closely related species. (ref. ID; 2894)
It is a small species with a kidney-shaped lorica (126 µm) that lacks anterior spines and protuberances. The toes are very variable; in some specimens they are of almost equal length while in others the left (39 µm) was considerably larger than the right (27 µm). Some specimens were found with five small sub-styles at the base of the toes, though only two are present in the mounted slides. The mastax is large (35 µm) and the trophi are very asymmetric. The left manubrium is 26 µm long and crutch-shaped. The right manubrium is greatly reduced, being almost vestigial. The fulcrum is long (27 µm) and crutch-shaped at its base. (ref. ID; 3334)
The body is short, thick, and strongly curved, so that the back forms an arc. The head sheath is marked off from the body and is composed of eight longitudinal folds. The two toes are more or less of the same length; the right one being slightly shorter. The left lateral antenna is situated slightly above the right one. The right manubrium of the trophi is visible only in some specimens. (ref. ID; 5936)
Comments
T. brachyura is very closely related T. cavia (Gosse), T. relicta Donner, T. vernalis Hauer and T. intermedia Stenroos. The trophi of T. brachyura resemble those of all this group in having a greatly reduced, almost vestigial right manubrium. Koste (1978) suggests that T. vernalis may be a synonym of T. brachyura, even though the left manubrium of the former ends in a continuous or smooth 'hockey stick' shape. The trophi of T. brachyura appear to be particularly similar to those of T. relicta both in shape of the alulae and the 'crutch' at the end of the left manubrium. (ref. ID; 3334)
Measurements
The length of the body (excluding the toes) was 78, 80, 98 µm, respectively. (ref. ID; 1450)
Body length 84; length of longest toe 27 µm. (ref. ID; 2825)
Length of head section 24; length of body 100; length of toes 24 and 30 µm. (ref. ID; 3127)
Length of body 89-111; maximum width 38; left toe 23-31; right toe 27; length of trophi 35; fulcrum 28; left manubrium 17 µm. (ref. ID; 5936)
Striated keel extending about less than 1/3 the length of lorica. Main toe distinct, longer than the length of lorica. (ref. ID; 1804)
The body as well as the trophi resembles T. bicristata. However, the differences can be easily discerned by close examination. The two keels on the body extend less than one-third of the body length. Also the body is short and slightly squat. Main toe longer than the body. The left manubrium is smaller than the right and has a small spoon shaped projection outwards which is not present in Hauer's (1965) drawing. Again there is a small spine-like extension from the right side of the rami-uncus complex. (ref. ID; 2715)
Measurements
Length of lorica 150; maximum width 75; main toe 165; right manubrium 36; left manubrium 20; fulcrum 40 µm. (ref. ID; 1804)
Length of body 138; width 69; main toe 144; trophi 50; length of fulcrum 40; right manubrium 36; left manubrium 20 µm. (ref. ID; 2715)
Body elongate and cylindrical. Large tooth forming a triangular projection from the median dorsal apart of the anterior margin of the lorica, overhanging the corona. Foot short, a conical structure, overhung on its dorsal surface by a roof-like backward projection of lorica. Main (left) toe nearly straight rod about half the length of the body; rudimentary right toe one-fourth to one-third the length of the main toe and lying across the proximal part of the latter; a small, scale-like substyle lying against the side of the main toe. (ref. ID; 3180)
The Ontario forms agree with the description of T. cavia in Donner (1950). There have existed some doubts whether T. cavia and T. bidens (Lucks, 1912) are same species (Donner 1950; Pejler 1962). The main difference between them is in the size, T. caiva measuring from 97 to 132 and T. bidens more than 151. Transitional forms between the two size groups have been observed by Donner (1950) and Hauer (1958). However, Wulfert (1961) has recognized T. bidens and describes it in detail. The specimens he examined had a body length ranging from 220 to 240. It is interesting to note the forms of T. cavia examined during the present study were smaller than the hitherto recorded forms. This species is found mainly among vegetation, especially Utricularia. (ref. ID; 5936)
Comments
The specimens referred to this species correspond in appearance to T. cavia (Gosse) as well as "T. bidens (Lucks)". Since the length of the lorica does not exceed 132 µm in any of them, they are, according to the account in Carlin (1939, pp.35-36), rightly classified as T. cavia. However, Donner, 1950, p.146 and Hauer 1958, p.39, report the existence of transitional forms between the two size groups. As size is the only distinguishing feature the two species must therefore, at least for the present, be regarded as synonymous. The common name for forms belonging here ought to be T. cavia (Gosse), which has priority. In "T. cavia s.str." a transverse striation similar to the one reported of "T. bidens" (Lucks 1912, Fig.12) can occasionally be observed on the anterior part of the body. (ref. ID; 1450)
Measurements
The length of lorica and that of the longest toe of several specimens measured were: 108 and 28; 122 and 32; 110 and 28; 123 and 20 µm. (ref. ID; 1450)
Total length 104-110 µm. (ref. ID; 2283)
Body length 95-115; body height 35-47; length of toes 24-30 µm. (ref. ID; 3275)
Length of body 90-125; maximum width 38; length of toe 25-29; length of trophi 35; fulcrum 25; left manubium 22 µm. (ref. ID; 5936)
Rattulus cylindricus var. chattoni de Beauchamp, 1907 (ref. ID; 1345); Trichocerca cylindrica var. chattoni Hutchinson, 1931 (ref. ID; 1345)
Descriptions
T. chattoni can be easily distinguished by its anterior spine which is fairly large and curved inwards. The head opening is folded in contracted specimens. On the dorsal side of the body starting from the anterior end there is a striped area running almost to the middle. (ref. ID; 2715)
Measurements
Length of body 177; width 72; anterior spine 30; main toe 105 µm. (ref. ID; 2715)
The lorica is plump, subcylindrical, slightly spindle-shaped and slightly compressed. Its left dorsal margin is evenly rounded, but the right ventral margin is almost straight. The dorsal ridge is long, extending most of the length of the body to a point joint over the foot opening. This ridge is rather low. The striated area is fairly narrow, but distinct. There is a definite constriction between the head and body. The head sheath is furnished with several folds. One dorsal and two ventral folds are particularly prominent. The foot opening is an asymmetric quadrilateral; its right lateral border is cut our shallowly, its left border much more deeply. The left toe is more than two thirds as long as the lorica and slightly sinuate. It is accompanied by a short scale-shaped substyle. The right toe is about a third as long as the left one and curved strongly to the left, either dorsal or ventral to the left toe. The foot is short and conical. The rami are asymmetric, the left one being slightly longer. They are narrowly wing-shaped with pointed alulae directed posteriorly. On the anterior tip of the right ramus is a row of small tuberculate teeth. In the corresponding position on the other ramus is a comb of slender teeth. The right manubrium is greatly reduced, and the right uncus consists only of two very slender teeth. The left manubrium is stout and long, and curved broadly at the distal end. It is attached to a stout, short uncus with stout teeth. The fulcrum is long and expanded posteriorly. (ref. ID; 2772)
Comments
Trichocerca compressa is closely related to T. lophoessa from which it differs in the lower ridge, proportions of toes, and the trophi. The two species are alike in general shape. (ref. ID; 2772)
Measurements
Length of body 166; length of left toe 93; length of right toe 32; length of head sheath 32; width of body 58 µm. (ref. ID; 2772)
This species has an anterior spine called a mucron which is bent but it is not as prominent as in T. chattoni. This species differs from T. chattoni in having a longer toe and a much longer, cylindrical body. (ref. ID; 2715)
Lorica asymmetrical. Body long slender. Anterior margin of lorica with folds and two teeth. Left toe more than half of the length of the body. Right toe much reduced. Gelatinous hull is produced by T. cylindrica only. This species carries the subitaneous eggs attached toe the body. (ref. ID; 2867)
The Ontario specimens agree with the description of Jennings (1903). Contracted specimens are usually seen with the anterior end closed by means of longitudinal folds. The mucron at the anterior end with its wide base is diagnostic. (ref. ID; 5936)
Male: Male present. (ref. ID; 3069)
Quote from ref. ID; 3069
Measurements
Body length 330-355; height 95-105; longest toe 270-290 µm. (ref. ID; 1402)
Total length 560 µm. (ref. ID; 2715)
Body length 196-220; length of left toe 220-282 µm. (ref. ID; 2825)
Total length 600; length of left toe 210 µm. (ref. ID; 2867)
Length of body 314-468; maximum width 114; left toe 190-328; right toe 21; mucron 30; length of trophi 50; fulcrum 36; manubrium 46 µm. (ref. ID; 5936)
The body is more or less cylindrical and the anterior end has many folds which close the head opening in contracted specimens. Two toes present. The longer left toe is half the length of the body. The mastax is diagnostic. (ref. ID; 2715)
Comments
T. dixon-nuttali closely resembles T. ruttneri Donner. However, T. dixon-nuttali can be recognised by its two toes and body which is more slender than that of T. ruttneri. (ref. ID; 2715)
Measurements
Body length 100 µm. (ref. ID; 2285)
Length of body 120; width 54; main toe 63; trophi 34 µm. (ref. ID; 2715)
Body length 95; toes 62 µm. (ref. ID; 2860)
Sub-styles very small. (ref. ID; 2317)
The left manubrium is straight, does not form a large hook, and only the terminal knob is inclined. It bears a thin, sigmoid, wing-like alula, which is unknown in the literature (Voigt 1957, Wulfert 1956). The right manubrium forms an S-shaped rod (usually it is straight). The right ramus is drawn to a long claw-like tip or alula with a second small tusk. (ref. ID; 2597)
The Ontario forms fit the description of Wulfert (1956), except that in many specimens examined the right manubrium is curved inwards at its end and is relatively longer. The right and left lateral antennae are situated towards the posterior end at the same level. Trophi are diagnostic. (ref. ID; 5936)
Measurements
Length of body 86; length of toe 128 µm. Sub-toe rudimentary. (ref. ID; 2284)
Length of body 160; length of toe 160 µm. (ref. ID; 2317)
Body length 270, main toe 23-240, second toe 54, mastax 67 µm. (ref. ID; 2597)
Total length 265; length of longest toe 100 µm. (ref. ID; 3275)
Length of body 244-300; maximum width 54; left toe 210-240; length of trophi 84; fulcrum 60; left manubrium 60; right manubrium 45 µm. (ref. ID; 5936)
The body is spindle-shaped and the cuticle is rather soft. There is no neck. There are two mucrones. The left mucro is large, strong and decurved; the right mucro is small and but slightly curved. It is crossed in front of the larger one. The head opening is marked by a few folds when contracted. The foot is rather long and is sharply set off from the rest of the body. The left toe is somewhat less than three-fourths of the length of the lorica. It is accompanied by a short spine. (ref. ID; 2771)
Comments
It is easily distinguished from all other Trichocercas with two mucrones by the shape of the body and the enormous size of the left mucro. (ref. ID; 2771)
Measurements
Length of lorica 160; length of foot 30; length of toe 100; greatest depth of body 52 µm. (ref. ID; 2771)
The index of toe length of body length is about 1.5. The body is broadly egg-shaped. The carina is highly vaulted with a broad field of stripes and reaches the beginning of the short foot segment. The left lateral antenna sits just behind the middle of the body. The dorsal antenna sits about left long toe is s-shaped and about half as long as the body with contracted head. The jaws are very big with crutches on fulcrum and left manubrium. The brain is big with a terminal eye. (ref. ID; 2834)
See Trichocerca hollaerti. (ref. ID; 3004)
Measurements
Body length 115-128; left toe 172; right toe 30; length of jaws 60-72; fulcrum 44; manubrium 40 µm. (ref. ID; 2834)
Trichocerca hollaerti is an easily recognisable species which, according to De Smet (1990), can be confused only with T. flagellata Hauer. Both species have a similar head aperture, disposition of the toes and substyli and a generally similar trophi structure. They can hardly be mistaken, considering that T. flagellata has a shallow and short dorsal keel, a rounder lorica and relatively long, smoothly curved left toe. However, as T. hollaerti is characterised by having a lateral keel over the entire body, by a head aperture having longitudinal folds and by having a single elongate right, and a S-shaped, short left toe, it resembles most T. lophoessa (Gosse). They differ only by the structure of their trophi, that of T. lophoessa has so far only been figured by Stemberger (1979). Especially its bifid left alulus and single-sided distal cruch of its left manubrium distinguishes T. lophoessa from T. hollaerti. (ref. ID; 3004)
The body is cylindrical, the dorsal side arched, and the ventral side almost straight. The head sheath is clearly marked off from the rest of the body and consists of a number of longitudinal folds. The foot is small and conical and the toe is straight and half as long as body. There are two substyles with wide bases on each side of the left and right toes. Trophi are diagnostic. The right manubrium is wanting and the left is straight. The rami have strong pointed teeth. The fulcrum is straight and ends in a spatupulate allula. (ref. ID; 5936)
Male: Males present. (ref. ID; 2284)
Measurements
The length of the body was 158 µm, the length of the toes 95 and 32 µm. (ref. ID; 1450)
Length of body 170; length of toe 70; length of sub-style 30 µm. The total length of the males is 36-46 µm. (ref. ID; 2284)
Body length 170; length of longest toe 90 µm. (ref. ID; 3275)
Length of body 162-172; maximum width 52; left toe 84-99; right toe 18; length of trophi 33; fulcrum 22; left manubrium 20 µm. (ref. ID; 5936)
This has long been considered a synonym for T. dixon-nuttalli (Jennings), but Hauer (1931) has recently shown that it is a distinct species. The body is much shorter and thicker than in T. dixon-nuttalli. (ref. ID; 2771)
Measurements
Length of the body 86 (of which 6 for foot); length of longest toe 44 µm. (ref. ID; 3275)
The specimen exactly agreed with the drawings and descriptions in Jennings (1903, p.311 and Pl.2:15-18) and Hauer (1931, pp.175-176 and Fig.2c). The vitellarium was distinctly lobed. In Jennings' picture of T. insignis (Pl.2:15) the vitellarium is more distinctly lobed than in almost all the other species described by him, and it seems probable that this characteristic is of taxonomic value. (ref. ID; 1450)
The forms found in Ontario agree with the description of Jennings (1903) and Hauer (1931). However, neither give drawings of the trophi. In the body a dorsal striated area runs to about two-thirds the length. Toes and substyles are diagnostic. The left manubrium is straight with a curve at the end and the right manubrium is short and feeble. Both rami and unci carry strong pointed teeth. The left ramus is larger than the right. These Ontario forms are smaller than those mentioned by Jennings (1903) and Hauer (1931). (ref. ID; 5936)
Measurements
Length of body (excluding the toes and teeth at the anterior margin) 230; greatest width (excluding ridge) 50 µm, length of the toes ca. 110 µm and ca. 50 µm. (ref. ID; 1450)
Length of body 205-257; maximum width 51; left toe 126-137; right toe 62; length of trophi 62; fulcrum 48; left manubrium 38; right manubrium 12 µm. (ref. ID; 5936)
This agrees with the description of Hauer (1937). However, the Ontario specimens are larger. The mucron at the anterior end is distinct. The right manubrium is feeble and degenerate, whereas the left one is long and robust. The unci and rami have a number of teeth, especially on the left ramus and uncus. (ref. ID; 5936)
Measurements
Length of body 115-122; maximum width 36; left toe 40-43; right toe 23; length of trophi 37; fulcrum 29; left manubrium 27; right manubrium 12 µm. (ref. ID; 5936)
The body is long, straight, cylindrical. Head stout, neck just indicated by a narrowing. Keel long, reaching to two-thirds of the body. Frontal end of keel is drawn into a long, slightly crooked thorn. Foot short, hardly visible. Toes set wide apart, main toe slender, faintly curved. Big red eye on the ganglion. Trophi of the usual form: right manubrium straight, thin, left manubrium longer with a bent terminal knob which is crutched if seen from the side. Fulcrum long, also crutched. The species is discussed in detail by Carlin (1939) under the synonym of T. scipio Gosse and re-described by Voigt (1957). (ref. ID; 2894)
Comments
The specimens found resemble those figured by Jennings (1963), Rylov (1926) and Carlin (1939) identified as T. (Rattulus) scipio (Gosse). Voigt (1957), however, pointed out that it is not the same species as described by Gosse (Hudson & Gosse 1886) but a new species which he called T. jenningsi. This species seems to be quite widespread, but when the name T. scipio is used and neither figure nor further notes are given, a definite identification of the recorded species cannot be made. (ref. ID; 3572)
Measurements
Length 220-225; frontal thorn 10; main toe 160; trophi 45 µm. (ref. ID; 2894)
Length of lorica 215-230; length of toes 167-177; length of toes 64-65 µm. (ref. ID; 3572)
The trophi structure of T. kostei n. sp. resembles that of T. tigris (O.F. Muller), T. pygocera Wiszniewski, T. porcellus (Gosse) and T. uncinata Voigt, but its external morphology is entirely different from any of these. (ref. ID; 2844)
Descriptions
Body elongate, slightly curved, relatively soft-loricated. Head aperture ventrally folded, otherwise smooth; right side ventrally with V-shaped concavity and broad lateral triangular projection. Dorsal keel relatively high, more or less half length of body. Foot short. Right toe half as long as left toe, both slightly curved. Three accessorial basal spines per toe: a broad-based ventral, two laterals. Trophus strongly asymmetrical. Fulcrum relatively long, broadened terminally. Right manubrium and uncus strongly reduced, right ramus with robust, fused supraunci, alula directed straight downwards. Left manubrium large, terminally broadened, strongly curved, with large external lamella. Unci teeth fused to a single, massive structure. Supraunci an inner ridge of teeth and an outer, curved, apically bifid structure, dorsally a rounded projection. Left alula large, bifid, projections curved around manubrium. Suprarami with sharp distal projection present. (ref. ID; 2844)
Male: Male unknown. (ref. ID; 2844)
T. kostei is especially characterised by its strongly asymmetric trophus. The fulcrum is long, and is terminally dilated forming a basal plate. Ventrally, these is a median crest starting from about midway to the tip of the fulcrum. It is connected to the left ramus by a basal and a proximal ligament. The right manubrium and uncus vestigial, and can only be seen as a short rod, projecting from between a ventral (fused supraunci) and a dorsal proximal projection of the right ramus, in dorsal proximal projection of the right ramus, in dorsal view, The right alulus is straight and points downwards. An external striation of the fused right supraunci is less evident is S.E.M. than using light microscopy, a striation of the inner side, on the other hand, is more apparent. The left ramus of the Indian specimens has a less differentiated suprauncus than in the Nigerian material, although the general shape is the same. The left alulus is bifid, with an elongate, outwardly directed external branch, having a curved tip and a rounded inner branch. The left uncus appears robust, and lies between the suprauncus and an antero-dorsal projection of the left ramus. The left manubrium is strong and has a conspicuous, large terminal crutch, bearing an external lamella. Suprarami are present both left and right, the right one is most conspicuous. Both bear a sharp distal projection, the left one has an additional shape, dorsal projection. The external morphology appears different from the Nigerian specimens. This, however, resulted from a slightly different orientation of the animal drawn, rather than being taxonomically significant. (ref. ID; 2923)
Etymology
The species is named after Dr. h.c.W. Koste. (ref. ID; 2844)
Measurements
Body length 178-196, width 46-54; left toe length 108, right toe length 54; fulcrum length 45; left manubrium length 40; left ramus length 31, width 22; right ramus length 33, width 6; uncus length 14 µm. (ref. ID; 2844)
The body is very broad, dorsoventrally compressed, and is asymmetrical. It is, therefore, very easily distinguished. The anterior end is made uneven due to a few projections. The lateral antennae are situated far posterior on the body. The left toe arises from the left side of the body and is straight and long. The right toe is small. Two substyles are visible and are broad based. Trophi is diagnostic. Both the unci and rami carry a number of teeth. The fulcrum and the left and right manubrium are straight. The right manubrium is not as prominent as the left. (ref. ID; 5936)
Measurements
Length of body 240, width 150; toe 200 µm. The specimens were much larger than those recorded by Jennings from America. (ref. ID; 3126)
Length of body 153-162; maximum width 108; left toe 99-110; length of trophi 36; fulcrum 28; left manubrium 32; right manubrium 26 µm. (ref. ID; 5936)
A fairly large rotifer which can be identified by the two anterior mucrons and the spindle-shaped body. Jennings (1903), Donner (1950), and Koste (1968) give thorough accounts of this species. Jennings (1903) mentions that the left lateral antenna is situated anterior to the right. But, as in the observations of Donner (1950), in all the specimens examined during this study, both the lateral antennae were situated at the same level. Six substyles were observed at the base of the toes. (ref. ID; 5936)
Measurements
In contrast to the majority of Trichocerca species T. longiseta varies considerably as to size. In specimens Pejler measured there was a continuous variation in body length (including teeth but excluding toes) between 200 µm and 315 µm. Even in one and the same population the size can vary quite considerably. In one of the two rock pools the body length of the individuals found was 210, 225, 235, 240, 250 and 257 µm. In the same individuals the length of the longest toe was as follows: not measurable because of deformation, 147, 162, 159, 159 and 172 µm respectively. There is a certain variation also in the width of the dorsal ridge. (ref. ID; 1450)
Length of body 250; width of body 80; length of toe 170 µm. (ref. ID; 3127)
Length body 230; toe 180 µm. (ref. ID; 3181)
Body length (contracted) 150-175; length of toe 170 µm. (ref. ID; 3275)
Length of body 296-331; maximum width 54; left toe 137-159; length of trophi 50; fulcrum 38; left manubrium 40; right manubrium 25 µm. (ref. ID; 5936)
Length of body (excluding toes) 148; greatest width 68 (the latter value does not tally with Olofsson's measurement in the text but on the other hand with his drawing); long toe 57; short toe 42 µm. (ref. ID; 1450)
Specimens varied in size; most measured just over 150 µm including the single foot spine, but the specimen depicted was somewhat larger. The members of this genus are remarkable for their asymmetrical trophi, which are adapted for suction, and for the asymmetry of the toes. In many species one toe only is left, usually as a long spine, as in Trichocerca marina, while in other members of the genus, the other toe is greatly reduced or very rudimentary. The front of the lorica. i.e. that part covering the head, is usually rather flexible. (ref. ID; 1419)
Marine. (ref. ID; 2281, 3170)
Marine and brackish water. (ref. ID; 3573)
In contracted specimens, the body is spindle shaped, widest in the middle and tapering gradually toward the ends. There is apparently no neck nor head sheath, the anterior end of the body being simply puckered. There is no mucro. A rather large dorsal fold projects slightly, giving the illusion of a mucro. In expanded specimens, on the other hand, there is a definite neck and head sheath. The obvious explanation is that the cuticle is so soft that it is completely smoothed out when the head is retracted. There are two very low, inconspicuous, striated ridges. The larger one, on the left, is about four-fifths of the length of the lorica. Both disappear gradually. The foot is of medium length, and truncately conical, nearly cylindrical. The left toe is long and straight, being somewhat more than two-thirds the length of the lorica. The right toe is very variable in length; it may be nearly one-third as long as the left toe, or it may be reduced to a minute style. The toes are accompanied by a minute spicule. The large eye is red and located under the left ridge. The corona bears two very long club-shaped processes which are sometimes bent sharply near the end. (ref. ID; 2771)
Measurements
Length of body 140; length of left toe 90; width of body 37 µm. (ref. ID; 2771)
The specimens found in Ontario agree with the description of material from the United States (Jennings 1903). However, Jennings (loc. cit.) gives no drawing of the trophi. These look almost symmetrical with both unci and rami carrying pointed teeth. The manubria are straight. The fulcrum ends in a spatulate allula. (ref. ID; 5936)
Measurements
Dimension are very constant throughout the season. Body length 190(180-200); height 100(95-105), longer toe 95-125 and shorter toe 12.5-16.5 µm. (ref. ID; 1402)
Length of body 168-198; maximum width 98; left toe 99-111; right toe 21; length of trophi 47; fulcrum 34; left manubrium 32; right manubrium 32 µm. (ref. ID; 5936)
The body is almost a cylinder. It is long and slender, the sides being gently curved. The small head is set off from the body by a definite constriction. There is one large, triangular mucro ending in a sharp point. Ventrally there are strong folds in the cuticle. The prominent ridge is about two-thirds as long as the body. The foot is a truncate cone. It carries a toe less than half as long as the body. The small toe is inconspicuous. (ref. ID; 2771)
Comments
Its nearest relative is T. iernis (Gosse) from which it differs in the general proportions and in the much greater development of the mucro in T. murchiearum. (ref. ID; 2771)
Measurements
Length of body 300; length of toe 100; greatest length of head (from neck to tip of mucro) 40; width of body 70 µm. (ref. ID; 2771)
The frontal margin can be smooth as well as have one indistinct thorn. Broad keel, red eyespot, the whole animal is reddish. The foot is cylindrical long single toe with two substyli. Trophi normal, fulcrum crutched, manubrium S-shaped with large alulae. (ref. ID; 2593)
Measurements
Body with foot 98-112 long, 55-70 wide; toe 130-145; mastax 50 µm. (ref. ID; 2593)
They are markedly asymmetrical with a large, forked alula of the left ramus and a strongly crutched left manubrium. A right manubrium cannot be seen. Trophi figures are given by Hauer (1936), Carlin (1939), Wulfert (1940), Donner (1950), and Godske Eriksen (in press), and they agree fairly well. (ref. ID; 3572)
The body is short and thick with the dorsal side arched and the ventral side straight. The head sheath is marked off from the rest of the body and the toes are curved inwards, towards the body. On the base of the toes, there are substyles with wide bases. The left manubrium is strong and axe-shaped, while the right manubrium is feeble and short. The left ramus and uncus carry stronger teeth than the right. (ref. ID; 5936)
Measurements
Length of lorica 108; length of toes 39 and 29; length of trophi 37-40 µm. (ref. ID; 3572)
Length of body 110-133; maximum width 44; left toe 32-43; right toe 18; length of trophi 38; fulcrum 25; left manubrium 23; right manubrium 10 µm. (ref. ID; 5936)
One subsytle is present. Although the toes are different in shape and size it is considered that the specimens are referable to this species. (ref. ID; 3126)
The body is fusiform, the head sheath clearly marked off from the body, and the anterior end has two broad-based spines. A dorsal striated area runs more than two-thirds the length of the body. The left lateral antenna is situated slightly anterior to the right one. The left manubrium is strong and straight with a short curve at the distal end. The right manubrium is thin and short. (ref. ID; 5936)
Measurements
Length of body 120, width 140; toes 60 and 20 µm. (ref. ID; 3126)
Length of body 187-208; maximum width 48; left toe 88-92; right toe 88; length of trophi 47; fulcrum 40; left manubrium 37; right manubrium 12 µm. (ref. ID; 5936)
The body is approximately cylindrical, broad, nearly three times as long as wide, twisted, and tapering posteriorly to a subcircular foot opening. When the head is seen in dorsal view, the twist of the body brings the foot into left lateral view. The head sheath is sharply set off from the rest of the lorica, and when contracted is provided a number of definite folds, of which two dorsal ones are very conspicuous. When the head is partly expanded, the dorsal folds are no longer prominent, but can usually be traced by careful examination. There is only one spine, small but easily visible on the right anterior margin of the head sheath. The dorsal ridge is well-developed, tapering from the head to the foot opening. The foot is short and nearly cylindrical. The toes are somewhat curved and lie in the direction of curvature of the body. The left toe is about half as long as the lorica (including head sheath). The right toe is slightly more than half as long as the left, but may in some specimens be two-thirds as long. No accessory styles were seen on the foot. The trophi are quite asymmetric, with rudimentary right manubrium and uncus, both slender rods. The left manubrium is well-developed, with the free end recurved broadly. The fulcrum is long and expanded at the posterior ends. The right ramus is massive, with small alula, while the left ramus is more slender with elongated alula. The left uncus has three slender teeth; in addition, three large teeth are to be seen on the ventral side of the left ramus, but a connection with the uncus was not seen. (ref. ID; 3196)
Comments
Trichocherca neeli resembles members of a group of highly asymmetric species with twisted bodies including T. insignis (Herrik), T. tortuosa (Myers), T. myersi (Hauer), T. insulana (Hauer) and T. euodonta (Hauer). From the first three of these, T. neeli differs in having but one spine on the head sheath. From T. insulana it differs in having very prominent dorsal folds on the head sheath, in the absence of prominent styles at the bases of the toes, and in the greater size of the left manubrium. It resembles T. euodonta most closely in the head sheath, but T. neeli has a less prominent spine, and the folds appear to be different; moreover, the toes are different in the two species. The trophi of T. euodonta have not been described. (ref. ID; 3196)
Type locality
This species appeared abundantly in collection from three beaches: West Pine Point on August 15, Grapevine Point on July 15, West End on July 10, and Deep Point on August 14, 1942. It was particularly common at West End Beach. (ref. ID; 3196)
Measurements
Total length of lorica, including head sheath 107; length of head sheath 21; length of right toe 26; length of left toe 52; length of spine on head 7; length of trophi 41 µm. (ref. ID; 3196)
The lorica is thin, transparent, fusiform dorsally and very conspicuously flattened from the side. The frontal opening is circular in the contracted animal with two semicircular folds visible. The neck is not indicated, the foot opening bears a short tail. The foot is short, left toe straight, the rudimentary right toe curved. There are several substyli. The inner organization is normal with a voluminous clear stomach. The virgate trophi are characterized by large alulae the left one being much larger. The left ramus has 10-12 comblike stout teeth, the right ramus 8-10 thinner ones. The fulcrum has an extended ribbed tip. (ref. ID; 2894)
The forms found in Ontario agree with the description of Myers (1934) of material from the United States. However, some of the Ontario specimens are larger (Chengalath & Fernando 1973). Myers (1934), in his drawings, has shown the lateral antennae to be lying at the same level, near the posterior third of the body. In a number of the specimens that we have examined we found that the left lateral antenna was situated anterior to the right. (ref. ID; 5936)
Measurements
Length of lorica 450; width 156; toe 235-240; mastax 96; in good agreement with the data of Myers (1934) and Chengalath and Mulamoottil (1975). (ref. ID; 2894)
Length of body 435-517; maximum width 168; left toe 240-299; right toe 89; length of trophi 106; fulcrum 76; left manubrium 71; right manubrium 62 µm. (ref. ID; 5936)
There is a rather great difference between the three specimens figured. The smallest specimen has relatively short toes and trophi. The frontal mucrones are small, and the neck is quite well-marked. The next specimen has a small lorica but relatively long toes and trophi. The mucrones are quite prominent, but the neck is only slightly marked. The largest specimen has a very large lorica but toes and trophi are not much longer than in the former specimen. The mucrones are fairly prominent, the neck constriction is absent. A dorsal keel on the lorica cannot be seen in any of the specimens. The trophi of the three specimens were not studied in detail, but the large, crutched left manubrium can be seen in all. The tooth on the left ramus is almost invisible. T. porcellus is known to vary mach in size and shape, and it certainly needs a further taxonomic-ecological study. (ref. ID; 3572)
The body is short, plump, and arched dorsally. Two small teeth are located dorsally at the anterior margin of the lorica. The posterior end is broad and rounded, and the head sheath is marked off from the body. The toes are curved inwards, towards the body. Each toe has two wide-based substyles. The trophi are highly asymmetrical, the left manubrium and ramus are greatly developed, but the right manubrium is thin and small. (ref. ID; 5936)
Measurements
Body length 163(145-174); body height 85(65-100), breadth around 90; longer toe around 53 and shorter toe around 35 µm. (ref. ID; 1402)
Total length 144; length of longer toe 46 µm. (ref. ID; 2825)
Length of body 230; toes 37 and 27 µm. (ref. ID; 3126)
Body length 110-115; body width 45-48; length of foot 5-10; length of toes 40-42 µm. (ref. ID; 3275)
Length of lorica 113-168; length of toes (the longest one) 38-50; length of trophi 46-52 µm. (ref. ID; 3572)
Length of body 131-154; maximum width 75; left toe 42-48; right toe 25; length of trophi 56; fulcrum 33; left manubrium 38 µm. (ref. ID; 5936)
Lorica oval, anterior end broader than posterior. Anterior margin of lorica with blunt foldings in preserved specimens. Toe single, bent at anterior end. (ref. ID; 1806)
Measurements
Body length 60; highest part 35; toes 35 µm. (ref. ID; 3083)
Distinguishable by it wide, usually striated keel extending up to 1/2 the length of body. (ref. ID; 1804)
T. rattus is distinguishable by its wide keel at the anterior end especially in lateral view. The keel is usually striated. The toe is long reaching up to the total body length. (ref. ID; 2715)
Distinguishable by its wide, usually striated keel at the anterior end, especially in lateral view. Toe long, reaching up to the total body length. (ref. ID; 3180)
A large rotifer found abundantly in all parts of the world. The dorsal striped keel and the trophi diagnostic. (ref. ID; 5936)
Measurements
Body length 230; maximum width 112; main toe 182; trophi 47 µm. (ref. ID; 1804)
The lorica length was 130 µm and the longest posterior spine was 120 µm long. (ref. ID; 2683)
Body length (contracted) 125-180; length of left toe 155-190 µm. (ref. ID; 3275)
Length of the body 185-222; maximum width 105; left toe 180-201; length of trophi 45; fulcrum 32; left manubrium 33; right manubrium 24 µm. (ref. ID; 5936)
The body length 185; the maximum width 87; length of the toes 190 and 16 µm. (ref. ID; 1450)
Body length 148; length of left toe 150 µm. (ref. ID; 2825)
It is a large species, in excess of 350 µm. The body is rotund or globose in shape, with a lorica 140 µm long and 100 µm wide. The body is naked, lacking anterior spines and prominences of any sort. There is no dorsal keel but there is a striated area, which is fairly level with the rest of the dorsal surface. This striated area extends backwards from the anterior margin for nearly two-thirds of the length and is 28 µm wide at all the widest point. The foot is short (18-25 µm) and is composed of two segments. The basal segment is stout while the other is so short that it is sometimes barely distinguishable. The left toe (198-208 µm) is extremely long and straight and between one and a quarter and one and a half times the length of the body. At the base of this toe there are at least six sub-styles, four placed dorsally and two ventrally, and a triangular, scale-like prominence that is dorsal to the left toe. The trophi are large (55 µm) and very asymmetric. The left manubrium is 44 µm long and at its lower extremity it is gently rounded, having an 'old-style hocky stick' shape. The greatly reduced right manubrium is long and thin, being about three-quarters the length of the left at 32 µm. It is also curved towards the fulcrum but in a gentler curve. The alula of the right ramus ends in a knob-like process, while the left ramus is bluntly furcate. The fulcrum is long (42 µm) and the lower extremity is expanded to a broad base. (ref. ID; 3334)
Comments
T. rattus globosa differs from the sensu strico T. rattus, especially in the globular or swollen form of the body. These two species lack the dorsal keel that is so prominent in T. rattus f. carinata (Ehrenberg), in T. bicristata (Gosse) and in T. lophoessa (Gosse). The Signy specimens are closely allied to T. rattus f. carinata, but lack the prominent dorsal keel. The trophi of T. rattus globosa are similar to those of T. rattus and to the form carinata and virtually identical to those of T. bicuspes (Pell). T. bicuspes differs from T. rattus globosa in the presence of prominent lateral spines. In view of the similarities, it seems reasonable of T. bicuspes to be considered as a subspecies of T. rattus that is very closely related to our subspecies. (ref. ID; 3334)
A small curved rotifer with its body tapering towards the posterior end. Donner (1950) and Wulfert (1961) described this species in detail. The ventral margin of the body is concave and the dorsal margin is convex. The head sheath is marked off from the body and the left and right toes are of the same length. The latter is one of the main characters which distinguishes this species from T. obtusidens Oloffson. Two substyles are present on either side of the toes. The left side of the trophi are much more prominent than the right. (ref. ID; 5936)
Measurements
Lorica length 75-115; left toe 27-33; right toe 17-27; trophi-fulcrum 28; manubrium 23 µm. (ref. ID; 1412)
Length of body 94-115; maximum width 34; left toe 31-34; right toe 31-34; length of trophi 31; fulcrum 20; left manubrium 18 µm. (ref. ID; 5936)
Body long, gibbous dorsally, almost straight ventrally. Two almost equal cusps and several folds on the contracted head. Keel long, stretching over 3/4 of body accompanied by a faint stripped field. Large red cerebral eye. Trophi normal, left manubrium thick and bent, right one straight and stick-like. Our specimens differ from is mentioned by Ruttner-Kolisko (1972) on p.189. There was no tail. (ref. ID; 2593)
Some specimens seem to lack the smaller mucro. This is probably dependent on the state of contraction of the front of the head, in which case a very small difference in contraction makes a very large difference in the appearance of the mucro, for all the specimens seemed well contracted. (ref. ID; 2771)
In lateral view, the posterior end of the lorica shows no sign of cleavage. In all my specimens this posterior margin of the lorica continues across in an unbroken line, which, on the dorsal side, by taking a sharp turn, continues downwards more obliquely. The pointed termination of the posterior end of the lorica is directed perpendicularly, or even takes a little bend upwards. The spine on the anterior margin of the lorica is slightly smaller that in drawing by Stenroos (1898). (ref. ID; 3036)
The lorica is elongate twisted and fusiform, the body width varying between specimens for one-third to one-half its length. The body tapers posteriorly to a spatula-shaped plate over the foot which is recurved in some specimens. There is one anterior mucrone and from the base of this a wide striated area extends to a point about three-quarters of the length of body. The ridge is low. The head sheath is short and separated from the body. There are two prominent folds, and several indistinct ones. The foot is sub conical and the longer toe is five-eighths of the body length. The smaller toe is one-eighth of the body length and is set at an angle of 60 degrees with the longer toe. Two small substyles are generally present, but one may be rudimentary or absent. The trophi are asymmetrical, and the manubrium is rod like and half the length of the fulcrum. The right uncus is also a thin rod. The left manubrium is robust and broadly bent at its posterior end. The left uncus is broad, curved, and has a blunt projection directed anteriorly. The left ramus has a long curved alula directed posterior-laterally and crossing the left manubrium. The right ramus has a triangular alula directed posteriorly. The right ramus of some specimens appears to have six or seven very fine teeth in the shape of a comb which are only seen in the ventral view, and them with difficulty. The fulcrum is robust and expanded at the base. The body of all specimens is opaque, and the internal organs could only be seen after clearing, when the organs appeared normal for the genus. An eyespot is present. Two distinct sizes were present in the samples: the larger specimens were more gibbous than the smaller forms which in some cases appeared almost conical in shape. The two sizes are however identical in all other characteristics. (ref. ID; 3126)
Comments
The main difference between the specimens found and T. rosea Stenroos, are that the former have only one mucrone, two prominent head folds, the striated area, and the smaller dimensions. Stenroos's description includes two mucrones, but it is probable that the second spine was merely the anterior edge of the lorica which in some positions looks like a mucrone. Berzins (1949) describes forms of T. rosea Stenroos having only one mucrone. (ref. ID; 3126)
Measurements
Body 162 long, 57 wide; toes 71 µm. (ref. ID; 2593)
Total length 378-385; length of lorica 210-215; width of lorica 60-73; length of left style 166-171; length of 1st substyle 32-26; length of 2nd substyle 10-11; length of 3rd substyle 7-8 µm. (ref. ID; 3036)
Large form: body length 170-185; max. width 80-90; toes 95-115 and 18-23 µm. (ref. ID; 3126)
Small form: body length 150-163; max. width 50-60; toes 90-110 and 17-22 µm. (ref. ID; 3126)
The body is cylindrical, but tapers at both ends. The head sheath is set off by a definite neck. There are two mucrones, the left slightly larger than the right. There are several folds on the ventral side of the head and a large one on the dorsal side on which stands the left mucro. The prominent ridge extends the entire length of the body. The body is a little more than three and one-half times as long as wide. The foot is quite short and cylindrical. The left toe is more than one-half the length of the lorica and is curved. The right toe is more than one-half the length of the lorica and is curved. The right toe is straight and is about one-third as long as the left toe. A scale-like substyle lies against the left toe. (ref. ID; 2771)
Comments
It resembles somewhat T. iernis, from which it differs in the possession of two mucrones rather than one, and in the proportions of the head. (ref. ID; 2771)
Measurements
Length of body 216; length of left toe 120; length of right toe 45; length foot 15; width of body 60; width of foot 20 µm. (ref. ID; 2771)
The small digitiform process on the corona can be well observed on the living animal; actually there are two of these, a smaller one situated behind the first large one. (ref. ID; 2593)
The forms found in Ontario agree with the description give in Donner (1953). The body is short and plump and the head sheath is not clearly marked off from the body. The trophi are more or less symmetrical. The ends of both manubria are bent. The rami and unci bear strong teeth. (ref. ID; 5936)
Measuremetns
Length of body 133-169; maximum width 66; left toe 53-54; right toe 21; length of trophi 48; fulcrum 37; left manubrium 37; right manubrium 33 µm. (ref. ID; 5936)
Anterior end with two equally long spines. Keel beginning from the base of the anterior spines and extending about 1/3 the body length. Foot apparently two-jointed. Toes short and unequal (ref. ID; 1804)
The anterior end has two spines of equal length. Starting from just below the spines are two keels with a striped area running down from about one-third of the body length. Foot clearly visible. Toes unequal and short. (ref. ID; 2715)
Specimens pertaining to this species would first key out as T. birostris (Minkiewicz). The distinction between both is, however, based on the structure of the foot (one or two joints, a very subjective character in contracted specimens) and the presence or absence of spinules between the two head-spines. Wulfert (1966) refers to difficulties in distinguishing these characters on Indian specimens identified as T. similis. Kutikowa (1970) has recently synonymized both species, a procedure which we here follow. (ref. ID; 2825)
SEM micrograph illustrating trophi. (ref. ID; 6844)
Male: Male present. (ref. ID; 3070)
Quote from ref. ID; 3070
Measurements
Body length 160; maximum width 42; right toe 46; left toe 32. (ref. ID; 1804)
Length of body 111; foot 6; toes 49; trophi 30 µm. (ref. ID; 2715)
Body length 142; length of longest toe 30 µm. (ref. ID; 2825)
Body length 140-150; widest part 49; highest part 50; foot 10; toes 45 (longer) µm. (ref. ID; 3083)
Trichocerca similis f. grandis (Hauer, 1965) (ref. ID; 1834, 2265 original paper, 2545, 2806)
The combination of the genera Trichocerca and Diurella has resulted in T. stylata becoming a homonym. Until the systematic position of these two animals has been described, the method adopted by other authors is being followed of including the original generic name before Eyferth's animal. (ref. ID; 3181)
Measurements
Length of body 180; maximum width 55; mucrones 35; toes 34 µm. (ref. ID; 3181)
This small Trichocerca species has a short and wide body. The width of body is more than half the length. Toes short and emerges from a prominent foot. The anterior end has folds but is usually wide. (ref. ID; 2715)
Measurements
Length of body 171; width 111; longest toe 60 µm. (ref. ID; 2715)
Length body 150; toe 50 µm. (ref. ID; 3181)
This form was described and figured by Bilfinger, in a paper which came just too late to be mentioned in my previous reported, as Coelopus brachiurus Gosse (?). (Bilfinger Zur Rotatorienfauna Wurttembergs, Zweiter Beitrag, Jahreshefte des Vereins fur vaterl. Naturkunde in Wurttemberg, 1894). As Bilfinger states, the animal is unquestionably a Rattulus and not a Coelopus. I have seen the two equal toes widely separated, then closed together again. Furthermore the toes are here very short (0.022 mm) both relatively and absolutely, forming only about one-seventh of the entire length of the animal (0.144 mm). I give Bilfinger's measurements, as they agree almost exactly with my own. But in Coelopus brachiurus as described and figured by Gosse, the toes are both relatively and absolutely much longer (0.043 mm), forming about one-fourth of the entire length of the animal. Mr. Charles Rousselet has been so good as to send me some farther notes and figure of Coelopus brachiurus Gosse, as found in England, and from these the distinctness of the two forms seem still more clear. Coelopus brachiurus swims commonly with the toes held straight out behind, according to Mr. Rousselet, whereas in many living specimens of this Rattulus which I have seen, the toes are always retracted, as shown in my own figures and that of Bilfinger. Bilfinger states also that in all specimens seen by him the toes were retracted. In Coelopus brachiurus, even when the toes are "thrust up under the belly", as figured by Gosse in the monograph, they are not held at all in the same position as in Rattulus sulcatus, being turned points forward instead of being retracted into the lorica in their natural position. The following then are the points of difference:
Coelopus brachiurus Gosse: Toes of the Coelopus type(?), length of toes 0.043 mm; total length 0.185 mm; toes nearly 1/4 of entire length; toes held straight out behind or curved, points forward.
Rattulus sulcatus Jennings: Toes equal and side by side (Rattulus type); length of toes 0.022 mm.; total length 0.144 mm.; toes about 1/7 of entire length; toes retracted with in the lorica.
It seems to me beyond question that the two forms are distinct. Mr. Rousselet suggested the possibility of the identify of this form with Coelopus porcellus Gosse, and set me mounted specimens of that form for comparison. The distinction is at once evident on comparing the two animals; moreover, Coelopus procellus is common in Michigan. I was acquainted with it before I saw this Rattulus. Rattulus sulcatus it seems to me then is certainly a species distinct from any hitherto described. (ref. ID; 3295)
The body is spindle-shaped with a mucron at the anterior end. The head sheath is composed of a number of longitudinal folds. A dorsal striped area runs to about half the length of the body from the anterior end. The left toe is straight and the right toe is small. The trophi have not been figured or described so far. The left side of the trophi is well-develped with a straight manubrium ending in a small curve. The rami have teeth and wide allulae. The fulcrum is straight and crutched. (ref. ID; 5936)
Measurements
Length of body 168-178; maximum width 60; left toe 93; right toe 19; length of trophi 46; fulcrum 37; left manubrium 37 µm. (ref. ID; 5936)
The body is cylindrical with a small anterior mucron. On the dorsal side there is a striated area running to about two-thirds the length of the body from the anterior end. The forms found in Ontario agree with the description of Donner (1950) of material from Southern Moravia. The trophi are asymmetrical with the left side well-developed. (ref. ID; 5936)
Comments
Probably both T. cuspidata (Stenroos) and T. unidens (Stenroos) belongs to T. tenuior, or at least to the same species-group. (ref. ID; 3572)
Measurements
Length of lorica 116-186; length of toes 55-75 and 29-35; length of trophi 42-49 µm. (ref. ID; 3572)
Length of body 120-162; maximum width 48; left toe 60-65; right toe 32; length of trophi 39; fulcrum 33; left manubrium 32 µm. (ref. ID; 5936)
Head shield clearly marked off from the body; composed of a number of longitudinal folds. Anterior mucron distinct and well developed. Right and left toes of equal length, with two broad-based substyles on both sides of each toe. (ref. ID; 1804)
Most of out mounted specimens show the head protruding some way beyond the anterior edge of the head shield or "hood', though the extent of this depends upon the degree of compression of the particular slide. Although we were able to clearly distinguish the trunk from the foot segment, the published data usually give just the body length. It was not possible to ascertain exactly how many sub-styles were present as they tended to lie flush with the base of each toe. The trophi, although considerably large, conform closely in all other respects with the published data for this species, bearing the characteristically massive anchor-shaped left manubrium (39-43 µm). The right manubirum, which is rudimentary, is long and thin and about three quarters the length of the left. The fulcrum ranged from 36 to 54 µm. (ref. ID; 3334)
The body is fusiform and the head sheath clearly marked off from the body and is composed of longitudinal folds. A well-developed anterior mucron is present. The posterior end of the body resembles that of T. fusiformis (Levander). The left and right toes are of equal length with two substyles having wide bases on both sides of each toe. The trophi are asymmetrical and the left manubrium is axe-shaped while the left ramus has a wide allula. The right manubrium is small and thin. (ref. ID; 5936)
Measurements
Body length 150; maximum width 50; toes 70-70; trophi 54 µm. (ref. ID; 1804)
Length of body 130-150; length of foot 20-28; length of toes 60-70 µm. (ref. ID; 3275)
Lorica length 180; toe 53; foot 23 µm. (ref. ID; 4606)
Length of body 129-140; maximum width 42; left toe 66; right toe 66; length of trophi 54; fulcrum 32; left manubrium 35; right manubrium 15 µm. (ref. ID; 5936)
Trichocerca tigris f. monostyla Russell, 1951 (ref. ID; 3126 original paper)
Descriptions
The new form is identical with that of T. tigris (Muller) except that the dorsal mucrone has disappeared and there is a moderate folding of the head sheath when the animal is contracted. With the exceptions noted the characteristics are typical of T. tigris. (ref. ID; 3126)
The body is thick and twice as long as the maximum width. The dorsal side is convex, and the ventral side is concave. The head sheath is only faintly marked off from the body and no spines are present on the anterior end. The toes are curved towards the body and both left and right toes are more or less of equal length. The trophi are asymmetrical and the left manubrium is straight with a small curve at the end. The right manubrium is strongly reduced. (ref. ID; 5936)
Measurements
Total length 100; length of longest toe 37 µm. (ref. ID; 2825)
Length of body 113-117; maximum width 57; left toe 32-35; right toe 32; length of trophi 37; fulcrum 28; left manubrium 23 µm. (ref. ID; 5936)
Body cylindrical, head slightly marked; distinct spine present on the right side of the anterior margin of lorica. Striated keel extending up to 2/3 of the length of dorsum. Toes almost equal, with two broad-based substyles at their bases. (ref. ID; 1804)
The forms found in Ontario agree with the description by Jennings (1903) of material from the Unites States. Both the right and left toes are more or less equal and on their bases there are two widely based substyles. The trophi are asymmetrical. (ref. ID; 5936)
Measurements
Body length 103; maximum width 42; left toe 45; right toe 38; trophi 45 µm. (ref. ID; 1804)
Body length 104-110; highest part 41-45; foot 20; toes 32-35 (longer) µm. (ref. ID; 3083)
Body length 115-155; length of toe 35-54 µm. (ref. ID; 3275)
Length 135; toe 44 µm. (ref. ID; 4606)
Length of body 103-115; maximum width 33; left toe 36-39; right toe 32; length of trophi 40; fulcrum 31; left manubrium 21; right manubrium 10 µm. (ref. ID; 5936)
