The World of Protozoa, Rotifera, Nematoda and Oligochaeta
Collotheca
Collotheca Harring, 1913 (ref. ID; 7815)
Class Rotatoria: Order Paedotrochida: Family Collothecidae (ref. ID; 7097)
Synonym Floscularia Ehrenberg, 1832 (ref. ID; 3688)
ref. ID; 1663
Corona very large, circular, lobed, or pointed. Setae not arranged in whorls. In a gelatinous tube. Foot terminated by a long, nonretractile peduncle, ending in an adhesive disc. Some species free-swimming. (ref. ID; 1663)
ref. ID; 1923
Mostly sessile, in clear, gelatinous tubes. Five species are free-swimming and may be found in lake plankton. There is question about the proper generic position of C. millsii and C. evansoni, which have very elongate lobes but whose setae are arranged differently from those of Stephanoceros fimbriatus. (ref. ID; 1923)
ref. ID; 2656
This genus is typical littoral sessile species. Harring (1913) listed 34 species, Berzins (1951) 56 species and Voigt (1957) mentioned 62 species. But only the following 10 taxa were found living in plankton either constantly or occasionally: C. ornata ornata (Ehrenberg, 1832), C. mutabilis (Hudson, 1885), C. pelagica (Rousselet, 1893), C. libera (Zacharias, 1894), C. discophora (Skorikov, 1903), C. lie-petterseni Berzins (1951), C. polyphema Harring (1914), C. ornata natans (Tschugunov, 1921), C. balatonica balatonica Varga (1936), C. balatonica rodewaldi Sladecek (1969), C. undulata Sladecek (1969). (ref. ID; 2656)
ref. ID; 3334
In this genus the margins of the corona are furnished with long, very fine setae. The foot ends in a peduncle. The digestive system is very characteristic. The mastax has incudate trophi. Mostly sessile forms, the Collothecans are usually found in clear, gelatinous tubes. (ref. ID; 3334)
ref. ID; 4596
Corona circular, usually lobed. Foot terminated by a contractile peduncle. (ref. ID; 4596)
Collotheca bjorki Berzins, 1976 (ref. ID; 4603 original paper)
Syn; Collotheca bilfingeri Koste, 1971 p.163, fig.1 Found also in Germany by Koste, but named 1971 as Collotheca bilfingeri. (ref. ID; 4603)
The original description of C. algicola (Hudson & Gosse, 1889) is quite unsatisfactory. The corona is not "precisely like that of F. ambigua" but has a much narrower dorsal lobe and smaller ventral lobes, being very similar to that shown by Edmondson for C. tenera (1939). The first specimen of C. tenera found in Wisconsin had what appeared to be symmetrical patches of dots on the corona as shown in figure of Hudson & Gosse's book, but these were found to be only a great number of small, dark granules in the body cavity which had been pushed up among the muscles of the corona giving a pattered appearance. As time passed, the granules were pushed around by the contractions of the corona, and the pattern disappeared. Such granules seem to appear in the body cavity of all aged Collothecae. The Wisconsin form evidently is C. algicola for the general form and habitat (Gloeotrichia) are the same. And the difficulty of observing such a small, transparent animal in a Gloeotrichia thicker easily explains the deficiencies in the original description. Because of these difficulties and the scarcity of material, a lateral view of the corona was not obtained, but it is certain that this form is very similar to C. tenera in all respects but the seven coronal bosses which are of a different nature from Hudson's dots. Therefore C. tenera should be regarded as a variety of C. algicola because the presence of several small raised areas of cuticule alone is not enough for specific separation. (ref. ID; 3259)
The taxonomy of this animal has puzzled us considerably, some of out specimens keying out as C. algicola (Hudson, 1886), other as true C. ambigua (Hudson, 1883). Voigt (1957), admitting a close relationship between both species, separates them on evidence of three characters: 1) the presence (algicola) or absence (ambigua), in regular arrays, of dark pigment granules in the corona; 2) the presence (ambigua) or absence (algicola) of a gelatinous tube; 3) a difference in size: C. algicola <400 µm; C. ambigua >500 µm. These are, with some formalization, the characters originally used by Hudson (1883, 1886), who first gave a rather superficial description of C. ambigua (Hudson, 1883). Three years later, in his classical monograph (Hudson, 1886), C. ambigua was redescribed in more detail and the description of C. algicola was added. Later authors (Edmondson 1940; Berzins 1951; Donner 1954) have accepted, or, at least, did not fundamentally criticize Hudson's data. Our material, however, showed considerable overlap and mixing in all three criteria mentioned above. Specimens alternatively showed no tube, a distinct tube or had a tube too thin to be visible. Specimens as large as 500 µm were extremely rare, falling all into the range of C. algicola, but then again, great variation was encountered in the amount of pigmentation. This ranged from complete absence to "traces", a slightly arrayed pigmentation or a distinct pigmentation. It has been shown (Sladecek 1962) that the amount of pigmentation in Collotheca is variable in general and that pigment granules tend to occur in sessile species but not in pelagic species. This observation rules out the diagnostic value of this character in the case f. algicola. The presence or absence of a gelatinous tube is probably not diagnostic either. Our specimens co-occurred with the well known C. ornata, which normally develops a tube, but in our material a fair number showed none. Moreover the latter species was as variable in size as C. ambigua itself. Therefore, it is concluded that all characters which have served in the past to separate C. ambigua from C. algicola fall within each other's range of variability. C. algicola must thus be considered a junior synonym of C. ambigua. (ref. ID; 2918)
In this species a peculiar current of body juice was observed. In extension the head of the animal is always coloured dark, even black, for it then contains a large quantity of pigmented bodies. When the rotifer is fully extended, and the corona spread out, the pigmented bodies flow away from the head and are distributed in the middle region of the body. They are not so conspicuous there, and sometimes it is difficult to notice them, as they are not concentrated in one place but distributed over a larger area. Extension of the rotifer is slow and even. The operating factor here is the pressure made by the body juice towards the head region, the corona. Muscles take no part in this action, but are almost completely loose. The sharp movement of contraction of the body, on the other hand, is produced by the musculature. It is comparatively easy to produce the sharp movement of contraction, for after complete extension the body juice has left the head region as so freed it from counterpressure, which would disturb the movement of contraction. It seems that there might be the same process of extension with the other species of Collotheca, too, but it is impossible to follow the process as the body juice is not pigmented or coloured. (ref. ID; 2738)
Measurements
Length of the specimens observed 500-600 µm. (ref. ID; 2738)
A ciliate circle along the coronal margin interrupted on ventral side, where a hyaline lamella is situated. Two very narrow tubercles carrying rigid setae are lying on both sides of this ventral lamella. (ref. ID; 2656)
Carrying at maximum 1 amictic egg. (ref. ID; 3192)
Collotheca bilfingeri Koste, 1971 p.163, fig.1 Found also in Germany by Koste, but named 1971 as Collotheca bilfingeri. (ref. ID; 4603)
Descriptions
Habitually the specimens have very wide corona in comparison with the relatively stout trunk. The coronal margin is almost even, but in the middle of the dorsal side there are two flattened, naked projections. On both sides of those, on a thickened coronal margin there is a tuft of vibratile cilia. Laterally (somewhat dorsally) on the thickened coronal margin there is a tuft of stiff cilia. Otherwise the coronal margin is free from cilia. The funnel of the mouth is very wide, but the proventriculus is small. In the stomach could be seen Trachelomonas. On the base of the foot there were two glands. (ref, ID; 4603)
Comments
The animals belong to the group of 2-lobed Collotheca; they open the corona first on the one side, and then the other side. I found the animals on anorganogenic bottom and in periphyton on Utricularia. (ref. ID; 4603)
Etymology
This species named in honour of my friend Professor Sven Bjork. (ref. ID; 4603)
Measurements
Total length 300-350; corona & body length 170-190; foot length 130-160, corona width 70; body max. width 50; ova 36x30 µm. (ref. ID; 4603)
There are plenty of five-lobed species of Collotheca. A new species must be added to this group, namely the specimens of Floscularia calva given by Bilfinger. In 1894 it was mentioned by Bilfinger that Hudson, in describing his Floscualria calva from scanty material, had not seen that there are 5 lobes instead of 2. It is difficult to believe this, as the description and drawing are very clear and distinct. (Hudson: - "Lobes two, short; dorsal lobe the large; setae very short, radiating from the thickened summits of the lobes, incapable of cilia-like action; body usually long and narrow, its outline confluent with that of the coronal cup, so that there is no neck; eyes cervical.") In no case can it be looked upon as five-lobed. Floscularia clava Hudson must therefore be acknowledged as a two-lobed species in future also. Such an opinion is confirmed by the fact that I had observed in Latvia a Collotheca which entirely agreed with the description of Floscularia clava given by Hudson, and not by Bilfinger. Montgomery (1903, 40) has rejected the recognition by Bilfinger by introducing Collotheca calva into the list of two-lobed species, rejecting the acknowledgment of a five-lobed species by Bilfinger - yet attributing the habitats of Bilfinger to Floscularia calva. A place must be found for the Collotheca mentioned by Bilfinger among the other five-lobed species. Some of the five-lobed species of Collotheca have short cilia, resembling the specimens described by Bilfinger. These three species are: Collotheca ferox (Penard), C. paradoxa (Penard), and C. trifidlobata (Pittock). Though the cilia of ferox are very short, the lateral lobes of this species are very well developed unlike those of specimens of Bilfinger. Further the trunk and the foot of ferox are not slender but much shorter, and the corona is larger and wide, infundibular. The other species, paradoxa, is not slender either; the dorsal lobe is very characteristic, square, large overarching the mouth cavity. The arrangement of other lobes is quite different. Habitually the animal mentioned by Bilfinger would resemble the slender trifidlobata much more strongly. Yet there is some difference. The head of the specimens of Bilfinger is not separated from the body by constriction (as that of calva Hudson), while trifidlobata has rather a remarkable constriction, so that the head and corona look conic. The dorsal lobe is substantial with a process on it - a point of similarity to some extent, but on closer examination a difference can be seen, for the tips of the lobe of trifidlobata is divided into three parts and entirely covered with cilia while the process of the specimens of Bilfinger is behind the lobes and the cilia, i.e., it is bare. Both the ventral lobes of trifidlobata are separated by a wide sinus but the lateral lobes are rather characteristic bulges on the coronal margin; cilia are not extremely short, as pointed out by Bilfinger. The description of the animals given by Bilfinger, therefore does not agree with any other description of a known species of Collotheca. I consider it a new species - Collotheca bilfingeri, with the following features: - body and foot very long and slender. Foot and body of about equal length. Corona a little wider than body, with five lobes. Both the ventral lobes conspicuous - separated by a notch from each other. Lateral lobes very low bulges on coronal margin. On the dorsal lobe behind a tuft of cilia a protuberance without cilia. On the tips of all the lobes extremely short cilia, vibratile. Sessile species with gelatinous tube. Observed by Bilfinger. (ref. ID; 2738)
There is a great likeness between this species and Collotheca edentata (Collins) and Collotheca voigti n. sp., although there is a difference in the shape of corona and arrangement of cilia. (ref. ID; 2738)
Descriptions
Body large and stout. Foot sharply separated from the oblong body; with a thin thread-like peduncle, with an infundibular distal end. Extended foot is only a little longer than trunk. Head cylindrical, rather long. Corona without lobes, forms a complete circle. Whole coronal margin covered with an uninterrupted line of very short cilia. Cilia of equal length. Cuticle of the head sparsely ornamented with minute wart-like projections. It seems to be dotted. Stomach consisting of two parts, large, always filled with some dark substance, which hinders us from getting more detailed knowledge about the inner organisation of the animal. At the base of the foot as well as at the distal end of it a pair of glands. Without eyes. Body covered with a large gelatinous tube. Normally 4 eggs can be seen in it. Food - diatoms, desmidea and flagellate. (ref. ID; 2738)
The animal has a certain likeness to Collotheca trilobata (Collins). The differences are: three projections with arrangement of cilia on each lobe and the more complicated structure of the foot. (ref. ID; 2738)
Descriptions
Body long and vigorous. A shallow constriction separates it from the head. Corona three-lobed. Lobes large, the dorsal a little larger than the other two. Small projections on the tips of the lobes, as well as on both sides of it. On these projections (total 9, three on each lobe) there are long vibratile setae, intermediate ones longer. Between the projections on the coronal margin rather sparse, short cilia. Head ornamented. Body finishes abruptly, merging into a sheath holding the foot. Foot very long and thin, too graceful for the robust body. The basal part of the foot smooth and much swollen. The thickening slightly constricted in the middle. The distal end of the foot is also somewhat thicker. It ends in a needle-like peduncle. The thin middle part of the foot usually forms sharp angles with spines on the edges. In contraction the basal part of the foot up to the constricted line is drawn into the sheath, the thickened part behind the constricted line forming a pellet. The remaining part of the foot contracts short and thick. At the base of the foot two glands. Flagellate come from the small vestibulum into the proventriculus, which seems to be green then. The food comes through the powerful trophic organs to the brown coloured stomach. Gastric glands large. The animal without eyes. Gelatinous tube not large, shapeless. Sessile species. (ref. ID; 2738)
Measurements
Total length 470-850; length of body 215-350; foot 255-500 µm. A large individual measured: total length 815; length of body 330; foot 485 (the thick basal part 105, thin distal part 380); width of body 115; corona 140; length of cilia (on projections) ca. 120 µm. (ref. ID; 2738)
The peduncle of the adult may be a third, half or (as in one instance noted) more than two-thirds of the length of the foot. It is like a stiff wire, and upon the death and disruption of the rotifer it is apart from the trophi, the only surviving remnant. (ref. ID; 2678)
Larva: The larva is of the characteristic maggot shape and organic constitution of a newly-hatched female Collothecid, with an incomplete circumapical belt of cilia, lateral and dorsal antennae just below this, well-developed trophi and oesophageal tube and prominent hyaline mucus glands in the stout foot. Very noticeable also in the foot, just above the terminal orifice, are two long, narrow nodose sacs from the anterior ends of which two ducts lead up into the body, with a pair of shorter and finer canals attaching the posterior ends of the sacs to the extremity of the foot. The nodules in these sacs produce the peduncular cement, and are analogous to the refringent globules which De Beauchamp was the first recognise as the elements exuded Stephanoceros fimbriatus (Goldfuss) to form an attachment cement. In longicaudata these minute bodies are not refringent, and they become fluid before extrusion. At the posterior end of the peduncular sacs there is a pencil of long active cilia which rarely extend beyond the pedal orifice. When the larva comes to rest on a substratum it at once contracts strongly, its head and foot being withdrawn and the body, reduced to about half its normal length, becoming thimble-shaped. Within a minute or two the body is seen to be rising, though the foot (constricted to a distinct neck at its junction with the body) remains pressed to the point of attachment. Presently the foot also joins in the movement away from the substratum, and it is then that the first portion of the peduncle becomes visible as a short column about 3 µm wide. In one observation the elongation of the peduncle and the elevation of the still strongly contracted body continued for some twenty minutes, at the end of which time the peduncle had reached a length of 90 µm, which proved to be its final limit. Very much longer peduncles were recorded. Upon the completion of the peduncle, which taper from the substratum to a width about one micron at its joint of emergence from the foot, the animal, perched upon this tenuous rod rests for twenty minutes or more, the trunk domed and the foot swollen, during which time the development of the corona is proceeding. When the head re-emerges the cilia are no longer vibratory but appear in short motionless tufts. Within an hour from the attachment of the larva, the dorsal lobe shows above the apical rim, and by this time the foot had lost its swollen appearance and has extended to a length equal to that of the peduncle. Subsequent progress is slow and noticeable chiefly in the further narrowing and lengthening of the foot and the enlargement of the corona. One example was seen to whip monads into its infundibulum within two hours of hatching from the egg. The tube of longicaudata has a symmetry unusual in the genus, being narrow about the peduncle and much broader about the foot and body. An explanation of this inverted bottle-shaped tube is found when watching the excretion of the peduncle, for both tube and peduncle are formed simultaneously. In the earliest stages of longicaudata the tube, being of almost the same refractive index as water, is difficult to glimpse, but it can be rendered beautifully distinct, light on a dark ground, by adding India ink to the mount. (ref. ID; 2678)
In C. campanulata longicaudata the peduncle is a stiff filament one-third or nearly half the length of the foot, which itself may be twice as long as the body of the Rotifer. Several published accounts of this species state that the peduncle is thrown into coils or loops when the animal retracts, but in the Cawston Heath specimens the terminal thread does no more than flex slightly, no matter how violent the contraction of the body. C. campanulata longicaudata is in other respects very like C. campanulata, having five spatulate lobes, but it is larger and of a more robust build, and when fully expanded presents (to the mundane mind) the appearance of a standard lamp, once so popular an ornament of out drawing-rooms. (ref. ID; 3215)
Corona of five lobes, bowl-shaped, about twice as wide as body; dorsal lobe largest, rounded evenly; lateral lobes smallest, but very distinct; ventral lobes almost as large as dorsal, well separated; neck (coincident vistibulum) a little wider than body, well set off from corona; body merging evenly into foot; foot long, slender; peduncle almost half as long as foot or longer. (ref. ID; 3259)
Comments
Collotheca campanulata longicaudata differ from the type in the great length of the peduncle. Moreover, all Wisconsin specimens of this variety had no expansion on the distal end of the peduncle. There are undoubtedly transitions between the two forms so the variation is continuous; nevertheless, it seems convenient to have a name for the form, with the longer peduncle, especially since it has been described and listed by a number of authors as a distinct species. All specimens of C. campanulata seen have had a definitely elongated peduncle. None has been seen with a very short one such as that found in C. ambigua and C. gracilipes. (ref. ID; 3259)
Measurements
Total length 300-800; corona width 100-150; peduncle 300-426 µm. (ref. ID; 2886)
Total length 377; peduncle length 95; foot length 143; body width 43; corona width 85 µm. Another specimen: total length 387; foot length 146; peduncle length 109 µm. (ref. ID; 3259)
Cubitt says: 'In the dorsal lobe the thickened ring is produced at its base into a rounded process at both angles, from each of which radiates a tuft of setae approaching in length those on the anterior knob. This, therefore, is the distinctive modification of the dorsal lobe in this species.' Though the discoverer laid such emphasis on the presence of these tufts at the base of the dorsal lobe (which, indeed, are very prominent) no further reference to them is made in later records of the species, so far as the present writer has been able to ascertain, from Hudson and Gosse to the present time, and they are omitted from drawings intended to represent Cubitt's animal. Weber (1898) would appear to be the only author, apart from Cubitt himself, who refers to the tufts when writing of the rotifer taken to be C. coronetta. His comment is, however, that he had not seen the 'lobules' which Cubitt indicated at the base of the dorsal lobe. Montgomery (1903), in his key, state that C. coronetta's lobes equal in length the width of the corona, and this implies that he had Cubitt's species in mind, though he does not mention the tufts; and the key given by Berzins (1951) does not note either the relative length of the lobes or the presence of tufts. (ref. ID; 2679)
Charles Cubitt, who was the first to find, describe and depict it, in 1869, likened its corona (with five long, slender erect lobes, each bearing a tuft of setae) to a coronet. He laid stress on another character in the following words: "In the dorsal lobe the thickened rim is produced at its base into a rounded process at both angles, from each of which radiates a tuft of setae approaching in length those on the anterior knob". Hudson & Gosse, whose monograph appeared twenty years later, and who were, of course, fully acquainted with what Cubitt had written and drawn (the borrowed one of his diagrams), made no mention of the paired tufts of setae, and did not show them in their figures. Dr. E.-F. Weber, in his "Faune Rotatorienne du Bassin du Leman" (1898) says he looked for the these tufts and failed to see them. There is a briefly description of C. coronetta by Dr. A. Collin is "Susswasser-fauna Deutshlands" (1912), but no reference to the basal tufts, and the character is similarity ignored in more recent papers and keys. Drawing by Weber and later observers show an animal with shorter and thicker lobes than those illustrated by the original describer, and in a private communication Herr Kurt Wulfert state that this form is very common in Germany. The present writer has seen Cubitt's animal, two fine examples of which were found in different seasons in Cheshire ponds, and so can compare it with the species or sub-species encountered in the Cawston areas, which has shorter thicker lobes and no paired tufts on the dorsal lobe. The latter form, which occurred during the autumn and winter months, appears to agree perfectly with the various accounts and illustrations published since Cubitt's time. It would seem that the type species is of rare occurrence and the short-lobed form has been widely and mistakenly accepted as being the animal discovered by Cubitt. (ref. ID; 3215)
Corona narrow, with five equal lobes; lobes long, slender in proximal portion, abruptly expanded about mid-length, distal portion being wider; setae on distal part long, on proximal part short; neck continuous with corona; body slender, conical; foot slender, about half total length; peduncle short; tube slender; animal sessile. (ref. ID; 2761)
Comments
Collotheca corynetis most closely resembles C. cornetta from which it is easily distinguished by the peculiar shape of the lobes. In a few specimens the proximal part of the lobe was considerably shorter than the distal part, the total length of the lobe thus being reduced. (ref. ID; 2761)
Measurements
Length total 700, foot 360, lobes 120; Depth body 100 µm. (ref. ID; 2761)
Body stout, oblong. Foot firm, a little longer than body. Corona a little wider than body, with 3 lobes. The dorsal lobe larger than the ventral lobes; with straight tip. Behind the dorsal lobe a single, broad fold-like, non-ciliated process; with rounded margin; without cilia. Without eyes. Foot with numerous foot-glands. Cuticle of partly contracted animal structureless, wrinkled and moreover, looked spines. Stomach filled with diatoms. Gelatinous tube shapeless. (ref. ID; 2738)
Measurements
Length 360-400; length of setae up to about 95 µm. (ref. ID; 2738)
Body cylindrical, sharply separated from the very long foot. Corona smooth, annular, without lobes, only a small ventral gap. On the coronal margin 3 not very big tufts of setae: one dorsal, the other two one on each side and not far from it (dorsolateral). The ventral and ventrolateral sides without cilia. Corona usually annular and the margin of constant thickness. Sometimes, however, a transient thickening of the dorsal wall may be observed. Foot very long and thin, with spiral edge along all its length, locked up in a more massive enlargement with a narrow infundibulum. Animal very hyaline. Without tube. Without eyes. Sessile species. (ref. ID; 2738)
Measurements
Total length 440; length of body 120; width of the body 60; corona 55 µm. (ref. ID; 2738)
The individuals from Lake Rusken were more elongated than Penard's specimens. The forepart of the trunk and the corona were of a more elongated build, and they form a funnel not so broad as is to seen in the drawings of Penard. Both the small ventral lobes are well rounded, but both the lateral lobes are larger, and have a triangular form, with a sharp point in the middle. The dorsal lobe is rectangular and strong. (ref. ID; 2738)
Measurements
Total length 540; length of trunk 175; length of foot 185; length of corona 180; length of setae on the dorsal lobe 45; width of trunk 90; width of corona 190 µm. (ref. ID; 2738)
Corona of five lobes, twice as wide as body, bowl-shaped, shallow; dorsal lobe long, fairly narrow, parallel-sided, truncate at tip, partly overhanging corona; lateral lobes quite low, but distinct, rounded; ventral lobes considerably larger than laterals, rounded, separated by broad, fairly shallow notch; setae long, continuous along margin of corona; neck well developed, narrow, sharply set off from corona and body; body slender, tapering toward posterior; foot very slender and extremely long in large specimens; peduncle quite short; dorsal antenna a small tubercle at base of corona; lateral antenna small but distinct cylinders with rather long setae; tube normal; animal sessile. The foot of this species grows faster than the body, so in young, smaller specimens it may be half of the total length, but in larger ones may be two-thirds of the total length. In old specimens, the tip of the foot seems to atrophy and shrivel up until the animal is left without direct connection with the substrate. Similar carious conditions have been observed in the dorsal antenna of Beauchampia crucigera; the sloughing of the lobes of Stephanoceros fimbriatus is well-known. (ref. ID; 2761)
This species was the largest rotifer found, with a length of 1200 µm when fully extended. The dorsal coronal lobe is enormous and curves inwards over the buccal funnel. The dorsal antenna is very prominent and is found just below the coronal cup. (ref. ID; 3334)
Egg: The eggs are brown and roughly circular (70 µm diameter) to elliptical (100 µm by 60 µm) in shape. (ref. ID; 3334)
Comments
Collotheca gracilipes is most closely related to C. campanulata, but is easily recognized by the characteristic shape of the dorsal lobe, the size of the lateral antennae and of the peduncle. Furthermore, the corona is folded differently in the two species when contracting; C. gracilipes first folds the dorsal lobe down into the coronal cup, pressing the other robes over it, then retracting the whole mass, while C. campanulata folds all five lobes together, then retracts them. (ref. ID; 2761)
Although Koste (1978) has recently reduced this species to a variety of C. campanulata (Dobie), we have retained the original designation. (ref. ID; 3334)
Measurements
Length: total 350, neck 60, body 170, foot 180, setae 90; Width: dorsal lobe 32, neck 60, body 50, corona 120 µm. Another specimen: length total 1665, corona 46 µm. Egg (amictic) 84x77 µm. (ref. ID; 2761)
Very characteristic species with a seven-lobed corona each lobe ending in a knob. No eyespots, contrary to previous observations. (ref. ID; 2593)
The corona showed 7 well developed lobes, the dorsal lobe was elongated and bent inward. All lobes showed knobs. Vibratile setae reaching up to 150 µm were present on the whole coronal margin, but showed their maximum length of the knobs. The gelatinous tube was large, entirely transparent and inconspicuous. Some detritus particles and diatoms fastened to it and betrayed it. The movements of the corona were slow. Two eggs observed at one old specimens seemed to be permanent eggs. They measured 57x45 µm. At the same old specimen the excretophores were seen in great numbers, namely at the extending of the rotifer. The food consisted of Gymnodinium and other coloured flagellates. (ref. ID; 2734)
Measurements
Total length 380-400; diameter of corona 140 µm. (ref. ID; 2593)
The total length of an old specimens reached 670 µm maximally, the length of the foot 320, the same of the body 230 µm. In the contracted state this specimens measured 250 µm in length. The distances between lobes in the corona measured 30 µm, the lobes about 13 µm. The dorsal lobe 45 µm, approximately. (ref. ID; 2734)
Corona of seven lobes; dorsal lobe triangular, elongate, often with slight knob; all other lobes definitely elongate, thick, cylindrical, un- or weakly knobbed; foot long, well set off from body; setation continuous; setae longest on tips of lobes. (ref. ID; 3259)
Comments
The corona of the seven-lobed Collothecae is so variable that they must be considered variation of one species. The heptabrachiata usually uncountered has very low, broad lobes with a small knob set on the rim of each, and the corona has a resemblance to that of C. ornata. Specimens have been found in which the knobs were borne on slender stalks. The variety diadema is distinguished by the thick, elongate lobes which may have slightly bulbous tips. Old members of the species frequently have the body so bloated and distorted that it is wider than the corona and the general appearance is so much different that one might be led to establish a false new species. Some Collotheca heptabrachiata have the intermediate lobs (those at the base of the dorsal lobe) greatly reduced in size so that the corona at first sight appears five-lobed. This has so far been observed only in old animals whose body was considerably wider than the neck and is further distinguished from C. ornata by the continuous setation of the corona and the vestiges of the intermediate lobes. It is not known if this reduction goes further. (ref. ID; 3259)
Measurements
Length of body 204; foot length 227; setae length 230 µm. (ref. ID; 3259)
Collotheca judayi Edmondson, 1940 (ref. ID; 3259 original paper) reported author and year? (ref. ID; 1923)
Descriptions
Corona wide, sides diverging toward anterior, with thin, filmy wall, thickly ciliated on entire inner surface of infundibulum, produced into five lobes; lobes long, slender, ciliated, easily sloughed, of irregular length in mature animals, occasionally completely lost in old animals; dorsal and lateral antennae small, conical papillae; foot short in young, very long in old specimens; peduncle very short; tube large, firm; animal sessile, often losing direct connection with substrate in old age. (ref. ID; 3259)
Male: Male present. (ref. ID; 3259)
Comments
Collotheca judayi is clearly separated from the other members of the genus by the shape of the corona and lobes and the ciliation of the lobes and infundibulum. It also shows a number of anatomical pecularities. There is a pair of flattened gastric glands attached to the dorsal anterior wall of the stomach and to the protonephridia and proventriculus by narrow ligament-like strands. A pad-like swelling of the hypodermis extends posteriorad along the ventral mid-line of the body from the edge of the corona. Just internal to this and lying almost against it is a median thickening of the wall of the vestibulum. There is a bilobed swelling of the hypodermis around the base of the dorsal antennae somewhat different in structure from that in abnormal Collotheca gracilipes. Whether it is a normal structure in this species is not known. The greatest difference in structure is a pair of caeca which extend from the sides of the intestine as far forward as the proventriculus. These are true caeca, being hollow extensions of the intestine, and not solid, glandular bodies similar to the structures which have been called caeca in the Flosculariidae. These are quite small and inconspicuous in young specimens, but enlarge greatly as the animal grows. The young animals are attached directly to the substrate and have long, equal lobes. As they grow older, the peduncle comes loose from the substrate, and the lobes slough off irregularly. In very old animals the tube extends far forwards, usually beyond the base of the lobes. The species eats a variety of algae and animals including small species of Lecane and Trichocerca. The male was seen hatching from the egg. It is different from the male of Collotheca campanulata in having a definite foot region. The male eggs are small (68x80 µm) and produced in large quantities. One adult female had laid three eggs in the tube and had twenty more in the body. (ref. ID; 3259)
Type locality
This species was first seen in 1918 in a small lake in Florida by Mr. F.J. Myers, being represented by a single specimen without lobes. (ref. ID; 3259)
Measurements
Total length 1805; length of lobes 400; length of foot 475; width of corona at base of lobes 400; width of body 305 µm. Total length 1960; lobes 653; foot 785 µm. Total length 2355; lobes 342; foot 1500 µm. (ref. ID; 3259)
The corona was almost like a circle, with the margin somewhat exposed dorsally, on which 6 stiff cilia were placed. The basis of the cilia continued deep into the margin of the corona as far as the ring muscle, which closed the mouth. Laterally on the margin there were two small projections with a tuft of vibratile cilia. It seems that this species should be called 2-lobed, as when opening the corona they raise one side firsts, and after this the another. The inner organization is of the usual type, with a mastax behind the proventriculum. The stomach is divided in two parts, with 2 glands above. Bladder small. The gelatinous cover is large, irregular and transparent. I found the animals on the border of the mire, in the zone of contact with the subsoil water. (ref. ID; 4603)
Etymology
This species is named in honour of my friend Dr. Ulf Lettevall. (ref. ID; 4603)
Measurements
Total length 200-250; head and body length 100-120; foot length 120-135 µm. (ref. ID; 4603)
Collotheca libera Harring, 1913 (ref. ID; 1345, 3688); Floscularia libera Zacharias, 1894 (ref. ID; 1345, 2738, 3208, 3275, 3688); Floscularia libera campanulata Linder, 1904 (ref. ID; 2738, 3688)
Descriptions
Male: The cilia are relatively soft, the eye is bright red. The penis had a simple outline, and seemed slightly cuticularized. It was flattened on one side. The vas deference is seen to be relatively wider. A closer examination from the broader side revealed a very fine bristle in either of the posterior "corners". (ref. ID; 2553)
A circular and unlobed corona with vibrating cilia 15 to 20 µm in length on the whole ciliary wreath without any interruption. It is 300 to 470 µm long and only 1 or 2 amictic eggs are carried within the highly transparent gelatinous tube. (ref. ID; 2656)
The Norwegian species - Floscularia sp. - with annular corona, without lobes, and with a complete ring of very short cilia on the coronal margin are unlike any other known Collotheca-species. Collotheca breviciliata have also a complete ring of very short cilia, but differs from the Lie-Pettersen form in the stout body, cylindrical corona, narrower than the trunk (trunk twice as wide as corona; without narrowed neck), while the Norwegian specimens have a broad, funnel like corona (one and a half times as wide as trunk; twice as wide as neck). I consider it a new species - Collotheca lie-petterseni, with the following features; - foot longer than trunk and corona, not firm. Trunk gradually narrowing into the foot. Corona broad, funnel like, twice as wide as the narrowed neck, and one and a half times as wide as the maximal breadth of trunk. Corona without lobes, annular. On the coronal margin homogeneous circle of very short cilia. Without eyes. Without tube?. Observed by Lie-Pettersen. (ref. ID; 2738)
The length of the body (excl. foot) was 150-270 µm, that of the foot 150-200 µm. The width at the corona was about one and a half times that of the thickest part of the trunk. Behind the corona the body was slightly compressed to form a neck. (In the biggest specimen the diameter was 115 µm at the corona, 78 µm at the narrowest part of the neck and 83 µm at the broadest part of the trunk). The corona was circular and unlobed. Its cilia were of uniform length, 15-20 µm. There was no interruption in the ciliary wreath. No eye-spots could be detected. The animals possessed a highly transparent gelatinous tube, which in two individuals contained an egg. (ref. ID; 3231)
Measurements
From Lake Straken: Total length 370; body length 170; body max. width 60; neck length 55; corona width 75-80; foot length 200; coronal cilia length 30 µm. (ref. ID; 4603)
Both the lateral lobes are large and wide, of equal size. The middle lobe is low, covered with rather short, stiff and vibratile cilia. Cilia on lateral lobes are stiff. On the foot a well shaped, broad spiral edge. (ref. ID; 2738)
Measurements
Individuals much smaller than those described by Milne. The total length of the individuals by Milne 850 µm, while mine only 240 µm. Length of body 115, foot 125 µm. (ref. ID; 2738)
It has been noted by Bilfinger that the specimens of Collotheca mutabilis observed by him had a gap in the ventral lobe thus forming two ventral lobes. In view of this they should be transferred to the three-lobed species group. In the species observed in Sweden as well as other localities (in Latvia) I have seen no gap in the ventral lobe. In all cases the ventral lobe has been smooth and uninterrupted. (ref. ID; 2738)
Descriptions
Body slender, long, cylindrical. Anterior end wider, with 2 coronal lobes. Gelatinous case large. Cilia on coronal lobes longer than on interlobal region. Mastax uncinate. (ref. ID; 1806)
The enlargement of the distal end of the foot was remarkable, though not onion-like, and it bore great resemblance to the shape of the distal end of the foot of Collotheca libera (Zacharias). (ref. ID; 2738)
Corona much wider than body, two-lobed (dorsal lobe larger). Vibratile setae set round the whole circle of the disc. Freshwater species, found in the eastern Baltic. (ref. ID; 4596)
Comments
Burckhardt (1943, p.369 and 1944, p.115) has made this species the subject of a detailed morphological investigation. His description differs in some respects from that given by Hudson and Gosse (1886, Pl.3:2). The present author's specimens agree, however, completely with those of Burckhardt. This seems to apply also to the individuals observed by Lie-Pettersen (1909) in Norway, by Hauer (1952) in Germany (Black Forest), and by Sladezek (1949) in Bohemia. Presumably Hudson has not devoted sufficient care to the study of his material. According to the present author's opinion there exists in this case hardly any reason for the assumption of a regional morphological variation. The earlier literature occasionally makes mention of a bulbous swelling upon the foot formed by the gland of the latter (see e.g. de Beauchamp 1909, pp.105 ff, and Burckhardt 1943, pp.372 ff). In all populations studied by the present author this swelling is well developed. Its shape resembles general that represented in Burckhardt (op. cit., p.370). (ref. ID; 2553)
This and C. libera are free-swimming, pelagic forms, whereas most of the species in the genus are sessile (i.e. the adult females are found attached to water-plants such as Myriophyllum, but the larvae and males are free-living). These, however, still retain the typical gelatinous sheath and toeless cylindrical foot of the genus, evidence that they have evolved from typical sessile ancestors. Like most (but no all) free-swimming "sessiles", they swim backwards. (ref. ID; 3208)
Measurements
The total length (apart from the gelatinous cover) was found to exhibit a continuous variation between the limits of 140 and 455 µm. The smallest individuals were newly hatched (or, more properly, recently emerged from the gelatinous cover of the mother individual). (ref. ID; 2553)
These individuals were also smaller than usual; length 178-225 µm. (ref. ID; 2738)
Length 200-500 µm. (ref. ID; 4596)
Adult: Coronal lobes 5, short, blunt, arranged pentagonally. Transparent case long, narrow and varied. Coronal lobes with long cilia, no interlobal cilia. Holdfast short. (ref. ID; 1806)
Egg: Newly deposited amictic eggs are dark, but they lighten during maturation. Before hatching, red eyespots as well as the ciliated corona and mastax may be distinguished. (ref. ID; 1821)
Larvae: Larvae have a long, worm-like body, divided into three regions: head, trunk, and foot. And they possess a circular wreath of relatively short cilia at the terminus of the head and of the foot. At the anterior end are two red eyespots set widely apart. The head is slightly broader than the trunk. Ganglion, a muscular mastax with well-developed trophi, two stomach glands, and a voluminous intestine are easily seen. These forms also possess red eyespots in the head region, but the lobes or arms of the adult animal are already present inserted inside of the head. Also visible is a large infundibulum, a vestibulum, a large mastax, and an intestine. An anus is usually visible, located in the middle part of the trunk. Larvae possess longitudinal hypodermal glands in the trunk. All internal organs usually obscured by abundant glandular inclusions. A dark oval formation which begins to brighten with the development of the larva is present. This body, which is probably identical to the anisotrophic (birefringent) crystalline structure (ACS) described by Wallace (1993), may function as an energy reserve for swimming and metamorphosis until the young animal begins feed. The foot is usually about 1/3 the total length of the body and contains two very prominent cement glands; the terminal part also contains small bladder-like glands. After constructing the basic tumbler the larvae withdraw into the short tube, remaining there without moving. When the young of these species complete this period of quietude, they extend from the tube and begin feeding and growing (including an increase in tube length). C. ornata have the lobes of their corona tucked inside the larval body with the distal ends pointing inwards. Therefore, the inactive period is actually one where developmental processes are very active. At this point the larvae are undergoing changes that lead to a reorganization of the coronal lobes. The red eyespots of the larvae usually disappear within three hours. (ref. ID; 1821)
Male: Male present. (ref. ID; 3070)
Quote from ref. ID; 3070
Corona of five lobes, shallow, bowl-shaped, half again as wide as body; dorsal lobe triangular, with spherical knobs; other lobes quite low, with knobs; setae limited to knobs; dorsal lobe with filiform process arising from dorsal mid-line just posterior to knob, of various length, extending forward beyond tip of dorsal lobe; neck narrow, body slender, with expansion at posterior end; peduncle short; anatomy normal; tube normal; animal sessile. (ref. ID; 3259)
It is a large species, in excess of 600 µm when fully extended. The margin of the coronal funnel bears five knobs. The dorsal knob is the longest and has a short finger-like projection (subspecies cornuta). (ref. ID; 3334)
Egg: The eggs are light brown and oval (45 µm by 25 µm). (ref. ID; 3334)
Comments
This variety differs from the type only in having the dorsal process which is subject to considerable variation in length from specimen to specimen. This is a continuous variation, for some individuals of cornuta have a very short process, and some specimens of ornata have a slightly protuberance just posterior to the knob on the dorsal lobe. Further evidence of the specific identity of the two forms was obtained by rearing a C. cornuta in a small aquarium; the three offspring found had no trace of a dorsal process. Specimens with quite short processes are rare so there is little difficulty in separating the forms, and they have been considered separate species for ninety years although the great similarity in form has been commented upon by several authors. It is proposed to limit the varietal name to specimens which have a process long enough to project beyond the tip of the dorsal lobe. The two forms frequently occur together in the same locality. (ref. ID; 3259)
Measurements
Length of one specimen 355; length of body 127, length of foot 190 µm. Another specimens: total length 425; length of body 175; length of foot 250 µm. (ref. ID; 2738)
Length of total 551; foot length 398; dorsal process length 51; width of corona 74; body width 34 µm. Another specimen: length of total 221; foot length 120; dorsal process length 28; width of corona 45; body width 28 µm. (ref. ID; 3259)
The dorsal lobe of the corona is larger than the other four. They carry long setae at the knobby tip but no cilia between the lobes. The long esophagus leads directly to the proventriculus but no mastax could be seen in any of the specimens. There is a big black eyespot at the rim of the corona, the internal organs are normal. The foot shows two swollen spindle-like portions, one at the height of the foot glands (mentioned by Berzins, 1951 & Donner, 1954) and an other one further down. The foot ends in a short (15 µm) thread. The tube is very gelatinous and transparent. (ref. ID; 2593)
Shape of body characteristic with a slight bulge towards the posterior end. The cilia at the anterior end thick and long. Foot long and ringed. Preserved specimens highly contracted. (ref. ID; 2715)
Tschugunoff (1921) found in the Caspian Sea a form called "C. ornata natans", which differs from the main form by the large sinus between the two ventral lobes of the corona and an onion-like enlargement of the distal part of the foot. (ref. ID; 3231)
Comments
Pejler (1962) found the same planktonic form in some Swedish lakes lacking the round sinus between the ventral lobes of the corona just like our animals, but he did not see any thickening of the foot. It seems therefore that there are indeed several ecological races ('sibling species' in Pejler's terminology). The distinction of the var. natans would seem to rest solely on its pelagic occurrence, a doubtful distinction. (ref. ID; 2593)
Measurements
Total length 290-350; foot 160; diameter of corona 55-60 µm. (ref. ID; 2593)
Total length 300; cilia 150 µm. (ref. ID; 2715)
A circular corona without any lobes, furnished with a wreath of vibratile cilia and within this five fleshy prominences directed inwards with short, stiff, radiating setae. It is 500 µm long and carries at maximum 5 amictic eggs. (ref. ID; 2656)
Corona without lobes, circular, narrow. Short vibratile cilia on the exterior coronal margin; longer non-vibratile setae on 5 projections of the inner margin. Freshwater species, also found in estuaries. (ref. ID; 4596)
Corona quadrate in plan and its base not wider than the body, with a flattened truncate lobe at each angle and a prominent lip on the ventral edge. No dorsal lobe. Long cilia on the lobes; on the dorsal and lateral rims of the corona an inner series of short inactive cilia, and an outer series of cilia in constant flagellatory motion. Long foot, frequently four times, or even more, the length of the corona and trunk combined. An outstanding peculiarity of this Collotheca is that, among the species with knobs or lobes, it is the only one so far reported with neither of these processes on the dorsal side of the corona. The knobs -mere flattened pads- extend only about 10 µm from the coronal rim, and are not erect, but set at right angles thereto. They carry cilia about three-quarters the length of the body. In the interlobular spaces on the dorsal and lateral edges of the corona there is an inner pallisade of shorter cilia, with rare and fitful activity, and an outer series of somewhat longer cilia which lash constantly inwards with a flagellatory motion. They display a rhythmic beat producing a slow optical wave. On the ventral side the rim of the corona is turned down like the lip of a jug, and it is bare of cilia. Though there is no knob or lobe on the dorsal rim, that part is thickened, and in two examples out of some scores examined a few long cilia radiated from that edge. Whether this is indicative of an incipient or retrogressive lobe or knob it is not possible to decide. In no specimen was there any break in the series of short cilia at that point. The contractile collar is very close to the rim of the corona, with the consequence that the infundibulum is very deep, occupying almost half the length of the body. Viewed dorsally or ventrally, the sides of the body from the rim of the corona down to the floor of the infundibulum are parallel, but in lateral aspect the venter and dorsum are swollen. From the inner walls of the infundibulum on the ventral side sprays of setae diaphragm starting from this same wall has on its free anterior ends two very prominent ciliated processes which, when viewed dorsally or ventrally, have the appearance of hooks. They are, however, broad blades, and their curved extremities reach almost to the level of the ventral rim of the corona. The dorso-lateral antennae are conspicuous tufts of setae starting from two well-marked humps and directed downwards. There is usually an eyespot at the anterior part of each hump, except occasionally in old specimens. With regard to the dorsal sense organ, the author is much puzzled, for it presents a form unlike that seen in any other Collothecid known to him. It appears to consist of a group of minute spherical bodies, usually three, seated on an ovoid pad of cells immediately below the contractile collar and connected therewith by two nerve threads. No sensory hairs could be made out. As a general rule the foot is about three times the length of the body, but in some examples noted it was four times the length of the body, and occasionally exceeded even this. There is a very short pedicel. The nest, which is difficult to see, appears to rise no higher than the cloaca. (ref. ID; 2679)
Male: The males was not observed. (ref. ID; 2679)
Egg: There is considerable variation in the dimensions of the amictic egg, from about 62x40 to 78x58 µm. The mictic (resting) eggs appear towards the end of August and are of the maximum size mentioned. They are among the most ornamental of all rotifer eggs, with a double shell, the inner one studded with a close-set series of cupped spindles joined by strands. They bear a marked resemblance to the eggs of the tardigrade, Macrobiotus hastatus and to those of a gastrotrich -a Chaetonotus species- seen by the author. (ref. ID; 2679)
Measurements
Total length 350-655; corona (excluding knobs) 70 wide; body 100-175 long; foot 250-525 µm long. (ref. ID; 2679)
Collotheca rasmae Berzins, 1951 (ref. ID; 2738 original paper) reported author and year? (ref. ID; 1345)
Diagnosis
Edmondson (1940, p.439) points to the great variability of Collotheca heptabrachiata, but the characteristic qualities of the animals described just now are so different and lie so well outside the limits of variability that the given species must be regarded as a well-distinguished species of the seven-lobed Collotheca. The very tall body and also the very distinct and characteristic arrangement of lobes and cilia give many good features for an independent species. (ref. ID; 2738)
Descriptions
The graceful body long, cylindrical. Head not set off from body. Corona narrow, only a little wider than body. Seven lobes on corona, in the shape of rather small, low bulges, rising only a little higher than the annular coronal margin. Dorsal lobe largest, broad, covered with rather short cilia. On each side of dorsal lobe a small lateral lobe covered with rather short cilia. The small ventral lobes also covered with rather short cilia. The remaining part of coronal margin bare, without cilia. Between both the ventral lobes the coronal margin forms a sharp curve. The curve continues downwards in a thin membrane, restricted on both side by the thickened walls of body. The membrane well, separated on the sides, but at the lower end it passes smoothly into the walls of body. Foot long, graceful, caudally thin, ends in a short peduncle. Foot covered with broad irregularly cogged spiral edge along all its length. Flagellata from vestibulum are drawn into the brown proventriculus and then come into the brown stomach through the strong trophi. Animal has no eyes. The oval, very transparent gelatinous tube covers only the caudal part of the foot. (ref. ID; 2738)
Measurements
Total length 245-535; length of body 125-170; foot 140-325 µm. The measurements of one individual: total length 435; length of body 165; foot 270; width of body 43; corona 46; length of cilia on dorsal lobe 22; length of cilia on lateral lobes 20; length of cilia on ventral lobes 17 µm. (ref. ID; 2738)
Corona consists of 3 lobes. The dorsal lobe is larger, two ventral lobes are a little smaller and not distinctly separated at the ventral side. Small vibratile cilia are found on all 3 lobes with an interruption at the ventral side. One group of stiff non-vibratile setae on the dorsal lobe. Corona is twice broader than the trunk. There is not a distinct neck. The trunk is cylindrical, slowly narrowing to the foot. Foot about of the same size as corona and trunk together. The posterior end of the foot with a spindle-shaped thickening. Without eyes. Without gelatinous. Amictic egg near the thickening. (ref. ID; 2860)
Comments
The nearest relative species is undoubtedly Collotheca atrochoides (Wierzejski), which is much bigger (total length 1400 µm), has a quite different foot (without the spindle-shaped thickening at the posterior end of the foot; foot can be totally dragged into the trunk). The new species is a clear-water form. (ref. ID; 2860)
Etymology
The new species is dedicated to Professor Dr. Fermin Rivera, Coordinator General de Invesitgacion, ENEP Iztacala. (ref. ID; 2860)
Measurements
Total length of the extended animal 250, width of corona 62, cilia about 15, setae 35, egg 38x28 µm. (ref. ID; 2860)
Collotheca stephanochaeta Edmondson, 1936 (ref. ID; 2771 original paper) reported author and year? (ref. ID; 2675)
Descriptions
This species has three lobes, one dorsal and two latero-ventral. The two lateral interlobular spaces are thickened, but hardly merit the term 'lobe'. The true lobes are broad and spatulate, and when fully extended by the adult often lean outwards at an angle. They are slightly broader than long, and there is little if any difference in their height, though in some specimens the dorsal lobe appears to be somewhat the tallest. The dorsal lobe is distinguished from the others by its straight, almost parallel sides, which however, show some constriction at the base where they join the rim of the corona. It has another peculiarity in the presence on either side at its base of what appears to be a duct leading from a large transparent gland. Edmondson noted this, but I was unable to make more than he could of these curious processes, and could not define them sufficiently clearly for a drawing. This lobe is more richly set with setae than the others. All have rounded summits; there are no knobs. The corona is wide - sometimes nearly half the whole length from tip of lobe to posterior end of trunk - and there is consequently an ample vestibulum. The striking characteristic of the animal is the presence of active setae and vibratile cilia, and their arrangement in alternate series on the lobes and the lateral interlobular spaces. At first glance the rotifer appears to bear long and sturdy spicules radiating from the tips of the lobes and standing stiffly from the inner and outer faces of the latter when viewed from the side. These ornaments are, as has been said, more numerous on the dorsal than on the latero-ventral lobes, but here as on all the lobes, they are of an evanescent character, and one or more may disappear as the animal changes its orientation. The explanation is that the 'spicules' are the optical effect of viewing, edge-on, series of setae in flat fans whose plane is at a right angle to the lobe they decorate. Their constitution and arrangement strongly recall those which are so typical of Stephanoceros fimbriatus. When one of these fans is seen in a frontal view it gives the appearance of a spicule broad at the base and tapering to the finest imaginable point. A lobe viewed from back or front is seen to carry four or five of the series giving this appearance of radiating spicules, but others on either side of these resolve into fans of setae, becoming more open as they are placed further down the sides of the lobes. The dorsal lobe appears to bear some twelve of these fans; the latero-ventral lobes half that number, and the lateral rims five each. The setae are very mobile, and in addition to the rapid whipping inward that is characteristic of other Collotheca species, some of the setae lash in more leisurely fashion. Between each pair of fans of setae, however, there are shorter veritable cilia, also set in flat fans at right angles to the lobes and vibrating without intermission. This arrangement of alternate groups of setae and cilia is seen most distinctly on the interlobular rims when these are turned directly to the observer, for there, as already mentioned, there are only five fans of setae, with cilia on either side of the central one, and there is less to confuse the eye. The appearance is ornate in the extreme. There are no setae or cilia on the ventral interlobular rim. The corona and vestibulum are very transparent, but the trunk, from the anterior part of the crop to the junction with the foot, is usually dense through being packed with food, and owing also, doubtless, to a thick and often much furrowed integument. In consequence, nothing of the internal organs could be made out beyond a generous germarium and an occasional hint of the oesophagus and trophi, which seemed to be normal. In nearly every specimen there was a collection of black or very dark brown granular matter at the posterior end of the stomach, and in some examples this was seen to move down in a than line into the well-defined intestine. The foot is nearly twice as long as the trunk, which tapers into it gradually. Broad muscles from the margin of the corona run down into it, and it has two prominent swellings, one at a third and the second at two-thirds of its length. Owing to the attachment of the rotifers to the inner sides of deeply concave moss leaves, it was not possible to make out the character of the toe. Edmondson, whose specimens more obligingly selected. Utricularia as an anchorage, says the foot ends with a swelling and a short peduncle. In my experience, the upper part of the tube was rarely seen above the edge of a leaf; in one instance where it was well displayed it did not rise higher than the posterior end of the trunk. The folding of the moss leaves when subjected to any degree of compression made a trough compulsory, and no objective of power higher than that of a 12 mm, could be employed. A dorsal sense organ was not seen, but two latero-ventral ones were plainly evident. They are pimples bearing setae situated at the broadest part of the trunk, just anterior to the trophi, and the setae are long and directed towards the foot in the extended individuals. When the animal contracts it becomes pyriform with the anterior end strongly puckered, reminiscent of a contracted Bdelloid. No coronal setae are then left exposed. The sensory hairs of the antennae are now directed towards the anterior end of the animal. Below the puckering mentioned the body is deeply cleft by long furrows. (ref. ID; 2675)
Egg: Eggs, usually three or four, were clustered at the base of the foot and apparently in contact with the plant. (ref. ID; 2675)
The corona consists of three large, rounded, nearly equal lobes. These lobes bear fairly short setae arranged in bands perpendicular to the rim, having an appearance much as in Stephanoceros fimbriatus. Often a wave of motion travels around the corona reminding one of the way the afore-mentioned species flicks its setae at its prey. There are several bands on the summits of the lobes and a few between, making six definite groups of setae on the corona. The interlobular setae are shorter than those on the lobes. They stand on elevations too low to be called even lobules. There is a short parallel-sided neck followed by a slender, conical body. The foot is smooth and definitely set off from the body. It is considerably longer than the body. The tip is bulbous and stands on a short peduncle. The internal anatomy is normal. The lateral antennae are very large and bear a brush of very long setae, one-half as long as those on the dorsal lobe. They are on the dorsal side quite near to the edge at the widest part of the body. The tube is large and transparent. (ref. ID; 2771)
The original description (Edmondson 1936 see: ref. ID; 2771) omits mention of a remarkable feature of the corona. Between each of the rows of setae which lie perpendicular to the edge of the lobes is a row of cilia which by their rather slow beating make a feeble but definite current toward the anterior. The anterior edge of each lobe is thickened and bears the cilia and setae while the sides are slightly concave. The specimen from Three Grass Lake had the posterior corners of the proventriculus produced posteriorad as two long pouches. The proventiculus and pouches were filled with a bright green Chlorella-like organism. (ref. ID; 3259)
Comments
Its nearest relative is C. trilobata from which it differs in the setation of the corona. The depressions between the lobes are much deeper and narrower in C. trilobata. (ref. ID; 2771)
Measurements
A well-grown specimen measured 750 µm from the tip of the dorsal lobe to the posterior end of the foot, one-third of this length being occupied by the corona and trunk. The corona was 98 µm wide across the rim, the vestibulum narrowing sharply to 57 µm at the contractile neck. The trunk widened quickly to 84 µm at its broadest part, and then fell off gradually to about 28 µm at the junction with the foot. The coronal setae measured 32 µm in length - slightly shorter than the width of the lobes. (ref. ID; 2675)
Total length 610; length of body (from tip of dorsal lobe to top of foot) 230; length of foot 375; length of peduncle 5; length of setae on dorsal lobe 40; length of setae on lateral antennae 20; width of corona 160 µm. (ref. ID; 2771)
Corona with five lobes, bowl-shaped, shallow, about twice as wide as body; dorsal lobe long, narrow, roughly triangular, its dorsal surface bearing seen small circular bosses; five bosses in transverse row, two others close together just anterior to the center one of these; lateral lobes very low, almost insignificant; ventral lobes low, but distinct, rounded, separated by a shallow, wide other; setae of moderate length, continuous around the margin of the corona; body subcylindrical; foot long, slender, abruptly set off from body; anatomy normal; tube apparently absent; animal living in Gloeotrichia clonies (Algae; Myxophaeceae). (ref. ID; 2761)
Comments
Collotheca tenera most closely resembles C. algicola from which it differs in the shape of the corona and the nature of the coronal decorations. C. algicola, according to the description of Hudson and Gosse (1889), possesses symmetrical patches of minute "dots". It may be that this is in the nature of a variation, the two species being identical. This view is strengthened by the similarity of habitat; however, in view of other apparent morphological differences, it is best to consider C. tenera as a distinct species until further observations can be made on C. algicola. (ref. ID; 2761)
Measurements
Length: total 148, corona 45, body 51 µm. Width: corona 51 neck 24 body 27, dorsal lobe at tip 12, foot at top 9 µm. (ref. ID; 2761)
In comparing the description and drawing of Collotheca tenuilobata (Anderson, 1889) with the description and drawing of Collotheca corynetis given by Edmondson in 1939, I see no difference to distinguish between them. The structure of body as well as the shape of corona and the arrangement of cilia are exactly the same, therefore they are to be considered as one species. Edmondson shows how to distinguished it from Collotheca coronetta (Cubitt) but does not mention Collotheca tenuilobata (Anderson). C. tenuilobata has once been regarded as synonymous with C. coronetta by Hood (1895, 29). These species however differ sufficiently from each other for them not to be regarded as synonymous, and coronetta as well as tenuilobata are retained. In comparing his corynetis with coronetta Edmondson has left unnoticed the fact that the tenuilobata considered synonymous with coronetta by Hood is in fact the corynetis described by him. Flosculaia coronetta var. Hudson is also synonymous with Collotheca tenuilobata: Lobes long, slender in proximal part, distal part enlarged; not confluent at their bases; setae on proximal part short, on distal part long. (ref. ID; 2738)
Differs from Collotheca heptabrachiata in having the large and thick lobes, the very short and stiff cilia there as well as the sinus in the ventral margin. It is also much more robust than the slender Collotheca rasmae, nov. spec., from which it differs also in the structure of the corona. Also the statement given by Edmondson concerning the high variability of Collotheca heptabrachiata allows us to look upon Collotheca thunmarki as a well distinguished species. (ref. ID; 2738)
Descriptions
The long, rather stout body narrows regularly into foot, not clearly separated. Corona as wide as body, with 7 lobes. Dorsal lobe large and strong. On each side close to it a rather small dorsolateral bulge. On each side a strong, stake-like lateral lobe. The upper part of these lobes is quite flat. On the ventral side corona forms a sinus. Close to each side of the sinus a not very large but quite robust ventral lobe. All the lobes, except the dorsal, lie on coronal margin. The tips of the lobes are highly refractive. Lobes covered with few very short cilia. Cilia stiff. On the inner side of the ventral sinus hyaline thickening of the wall of the body. Vestibulum separated from the large proventriculus by a well formed and conspicuous diaphragm. Proventriculus brownish-green, filled with Flagellata. The food in the rather large stomach has become brown. Foot firm, a little longer than body. Without eyes. The animal very hyaline. Small gelatinous tube covers only foot. (ref. ID; 2738)
Measurements
Total length 500; length of body 230; foot 270; width of body 85; corona 90 µm. (ref. ID; 2738)
This small five-lobed sessile, distinguished by two groups of radiating cilia and a finger-like process on the dorsal lobe, was discovered by Dr. George M. Pittock in the Minster Marshes, Thanet, in 1895. (ref. ID; 3215)
Corona large, trilobed, one of them larger, giving appearance of a hood. Cilia on coronal lobes larger than in interlobal region. Transparent case wide; holdfast short, stout. (ref. ID; 1806)
The long, vibratile setae, situated along the whole coronal margin can be very clearly seen. (ref. ID; 2738)
Dr. C.T. Hudson wrote (The Rotifera or Wheel Animalcules, 1889): "The first thing that strikes the observer, on watching the protrusion of the furled head, is the great size of the Floscule, and the curiously shrivelled appearance that the lobes of the coronal cup present as they emerge from the opening head. They look exactly as if the animal were sickly or injured. In a few seconds, however, the gently swell out, the many folds and creases disappear, till at last the eye is gratified with the sight of a lovely transparent tulip of three petals, their edges all fringed with delicate motionless hairs". When the coronal cup is retracted and the outer cuticle puckered above it, like the tied neck of a sack, the prominent dorsal antenna protrudes well above the puckers, and its spray of setae is plainly visible. This is due to the fact that the antenna, which is very much developed in this species, is not attached to the dorsal lobe by to the cuticular collar which close over the contracted corona. (ref. ID; 3215)
Measurements
Total length of the animal observed 500-700 µm. (ref. ID; 2738)
Corona circular with undulated margin; on 5 low and even tubercles there are 5 groups of short vibratile cilia showing a length of 1/5 of the corona diameter. No stiff setae. Eyes absent in adult specimens. Body very elongated. Corona equal or slightly broader than the trunk. Trunk cylindrical, slowly narrowing to the foot. Foot 1+1/2 to twice as long as the other body, equally broad with an obtuse ending. Up to 11 amictic eggs at one female. Gelatinous case absolutely hyaline. (ref. ID; 2656)
Measurements
Total length without cilia 500 µm, cilia 15 µm. Length of the trunk 170 µm, its width 70 µm, width of corona 77 µm, length of the foot 330 µm, its width 10 µm. Amictic eggs 44x32 µm, freshly born larvae with 2 eyes 100x22 µm. (ref. ID; 2656)
The body is long, cylindrical, with a circular smooth corona about the width of the trunk. There are no lobes or setae, only a row of very short cilia interrupted by a small ventral notch. Otherwise the dorsal and ventral appearance is identical. The neck is somewhat narrower than the trunk. The foot is separated sharply, wrinkled, about one third of the total length, ending in a short peduncle. There are no eyespots and in the grown specimens seen there was mastax either, A big yellow pro-ventriculus is connected by a short oesophagus to the large stomach. The ovary is clear, colorless. There is a large bladder. The species is sessile but no tube could be detected. The few animals seen were very slow, sluggish, living among the first filamentous algae growing in icy water on Apr. 30, but have not been found again since. (ref. ID; 2894)
Comments
The species closely related to C. edentata (Collins) 1872, but differs from this in the absence of a gelatinous tube and a much narrower corona which dose not form a ballooning funnel. The corona also distinguishes it from C. tubiformis Nipkown, 1961, which according to Berzins (1951) is related to C. lie-petterseni Berzins, 1951. (ref. ID; 2894)
Etymology
The new species is named in memory of the late Prof. Lajos Varga, the noted Hungarian rotifer expert and soil zoologist. (ref. ID; 2894)
Measurements
Total length 420-450; foot 150-160; width of trunk 140-160 µm. (ref. ID; 2894)
Body vigorous and fat, sharply separated from foot. Head cylindrical, not long, without lobes. Coronal margin thickly covered with rather long vibratile cilia in a complete ring. Cilia of equal length. The annular edge of the corona urn-like, turned up and outwards. The cuticle of the head with tiny dots. Foot and trunk of equal length. Foot ends directly in a funnel-like peduncle (without a mediate threadlike part of peduncle). A single pair of glands at the proximal end of the foot. Stomach large, brown, filled with diatoms. Without eyes. The large and transparent gelatinous tube cylindrical. Some foreign bodies fastened to it, such as small bits of glimmer, granules of sand. This sessile species is very slow in the body movements. Movements of cilia lively. (ref. ID; 2738)
Measurements
Total length 400; length of body 200, foot 200, width of the body 135, corona 90; length of cilia 70-80 µm. (ref. ID; 2738)
Collotheca volutata O. Sebestyen & Varga, 1949-1950 (ref. ID; 3528 original paper, 3688)
Descriptions
The tube of female: The animal when withdrawn inside the tube has a cystlike appearance, with a rather transparent and colorless outer coat and a core of a pinkish shade. The shape and size of the tube vary: in general it has the shape of a barrel or sack, with a darker base and a narrow opening. The axis running through the center of the base of the tube and its opening is curved somewhat. It is made of a gelatinous substance, secreted by the rotifer, and is more adhesive than the cases of other members of the genus. The substance of the base (sole) of the tube seems to be more compact than that of the side walls, and has a rather indefinite spiral structure. It continues toward the inside to the tube in a small mound, to the upper surface of which the rotifer is attached. The more or less cylindrical wall is made up of a more delicate material in which empty valves of Diatoms are imbedded in abundance, they - very likely - originate from the excretum of the rotifer. Such elements are lacking both in the sole and the mound. Around the opening of the tube, which is usually an irregular circle, the wall seems to be more delicate. The diameter of the opening is much smaller, than that of the tube or the base, but large enough to allow the animal a comfortable passage through it. Minute particles both of organic and inorganic material adhere to the surface of the tube. When treated with hydrochloric acid, the inorganic particles disappear and the valves of Diatoms become visible, demonstrating their abundancy and variety. Not infrequently a bunch of Diatoms may be found in the cavity of the tube, still exhibiting the characteristic brown color of the algae. The origin of such masses has not as yet been discovered. A few indefinite circular rings on the wall might be due to periodicity in manufacturing the case. As mentioned, the animal is attached by its foot to the upper surface of the mound, this being the only place of attachment. When drawn inside, the body is surrounded on all sides by the cavity of the tube, this being the case with members of the Melicerta and Limnias genera too. In this sense our animal differs definitely from all the other tube-living Collotheca species known, because, they being attached to the opening of the tube too, the proximal part of the tube turns inward on contraction and when extending, it turns inside out. The large size of the tube in proportion to that of the body is also characteristic, together with the presence of empty valves of Diatoms in the substance of the wall. These minute but rigid particles give firmness to the tube, while the elasticity of the wall is due to the gelatinous secretion of which the tube is made. Both properties of the tube, viz. firmness and elasticity, have some advantage since this rotifer, being unattached to any firm substratum is exposed to various disturbances caused by frequent wave action. It might be rolled and tossed about among the detritus particles or dispersed in the water, to sink again without any damage being done either to the tube or to its inhabitant. The tube protects the resting egg too, after the mother's death and provides for the distribution of the species, through the above-mentioned properties, amidst the peculiar dynamic vicissitudes of the habitat. (ref. ID; 3528)
The body of female: As to the main features, the female C. volutata resembles the other members of the genus in general, though it seems to be more delicate, the body is slightly bent ventrally, its main axis exhibiting a curve similar to the tube. The cuticle is delicate and transparent. Folds and creases appear in great numbers on the surface of the body, resulting in a warty outline. However, these wrinkles are apt to disappearance soon. A few ringlike folds are frequently seen on the neck. The folds and creases on the foot are permanent. The division of the body into head, neck, trunk and foot is distinct. The proportion of the head+neck:trunk:foot is about 2.5:5:3. (ref. ID; 3528)
The head of female: At the base of the corona, a delicate circular membrane, the velum, is present. The disc forms five semiglobular lobes arranged regularly. The dorsal one, nearly a complete sphere, is drawn out a bit above the others, owing this position to the presence of a very short stalk, contrary to the other ones which sit immediately on the disc. The dorsal lobe is halfway enveloped by a delicate membrane reaching only halfway lengthwise and not extending above the lobes into the coronal net, as in the case of C. cornuta. This lobelike membrane lacks both cilia and "bristles". The coronal lobes carry the delicate long rod-like cilia ("bristles") which do not beat and are peculiar to the genus. The length of the longest bristles is about equal to the diameter of the disc. The withdrawal of the corona happened quickly, and when but incompletely done, the bristles form one unit resembling a paint-brush. The upper part of the bunch remains outside and is visible, while the lower part, hidden in the infundibulum, could not be detected, though the outline of the coronal lobes shows through the cuticle. When in extension, which is a slow, a gradual -one might say a cautious- process, the situation just described recurs, very soon the disc bearing the lobes unfolds, the five bunches of delicate bristle spread out and the appearance of the velum marks the end of the process. The velum, though but a very delicate membrane, seems to take part in the stiffening the corona. The edge of the disc between the lobes carry a row of minute cilia, the presence of which is characteristic of our species. On other members of the same genus they are missing, with the exception of C. coronetta. The surface of the infundibulum is also covered with cilia, especially, the ventral part. By the beat of these cilia a current propels the food towards the mouth. The cilia covering the inner surface of the lobes take part in the same process. Minute granules in the subcircular plasma below the corona could distinctly be seen through the transparent and colorless cuticle of the neck. These granules, uniform in size, have a high degree of refraction, and are in constant motion. Inside the neck the cone-shaped infundibulum is situated, its narrow basal opening continues into the wide vestibulum, at the posterior end of which the mouth is located. The opening of the mouth falls below the neck, on the anterior part of the trunk. Eyes are lacking on the adult female, though a pair of hemispherical purple-red eye-spots, without lenses could be seen through the egg-shell of the embryo. The dorsal antenna with a few short setae is situated on a minute mound on the neck, just above the brain, which in turn has an elongated pear-like shape. When the body is extended usually only the corona and part of the neck can seen outside the tube. (ref. ID; 3528)
The trunk of female: The neck widens abruptly to the voluminous trunk, which is dorsally somewhat swollen. In its upper part -as has been mentioned- the mouth is located. This opens into the slender oesophagnus. On the bottom of the mastax, the rather degenerated trophi are found: on the upper part of the fulcrum, which is minute and rod-shaped, there are the two leaf-like rami. To the manubrium, which has the shape of a disc, the unci are attached. These being slightly bent, have the form of a dart and are joined at their base. The rigid valves of the Diatoms could not be ground by the delicate trophi, the role of the jaws being rather to push forward the food into the succeeding parts of the alimentary canal. Both the mastax and the stomach lie immediately under the subcircular plasma layer, and are in most cases stuffed to their highest capacity with Diatoms of various sizes and shapes, so that they extend mostly to the base of the neck, right into the neighbourhood of the brain. The globular salivary glands are located on both sides of the upper edges of the stomach, as usual. The short and wide intestine generally contains empty valves in abundance. The rectum, also a short and wide part, presses the bulk of the valves through the anus out of the body into the inside of the tube. The anus is located dorsally above the foot as usual. The great bulk of food enclosed by the stomach exhibits the characteristic brown color of Diatoms. Through the cuticle the outline of the valves could be distinctly seen. The tubules of the excretory organ could be detected from the middle of the trunk on, on the ventral side. The contractile vesicle is rather voluminous. The excretum is expelled through the cloaca into the cavity of the case. The globular ovaries with the yolk-gland lie ventral to the intestine. Sometimes 3-4 parthenogenetic eggs -in different phases of development- could be seen in the body. After being discharged they keep the globular shape for a while. Their content seems to be compact. Since the development of the embryo beings within the mother's body, no nuclei could be seen. The eggs are attached to the wall of the tube, in contrast to most of the other members of the genus, where they are attached to the foot of the female. The eggs soon assume an oval shape and their content are no more homogeneous. It has been mentioned that the developing embryo has a pair of eye-spots. The oval-shaped resting eggs have a deep yellow color, are enveloped by a thick membrane, on the surface of which minute projections with blunt ends are scattered in regular distribution. On the outer surface of the resting eggs, freshly discharged, a second membrane could be seen laying close to the projection; however the ends of the latter are not fixed to the membrane. Later on this membrane disappears. Its role might be the protection of the oviduct, etc., during the passage of the egg, against the injuries which might be caused by the rough surface. No such outer membrane has been described of any other rotifers. The number of resting eggs - in contrast to all other members of genus - is high. This fact perhaps has something to do with the structure of the egg, viz. the presence of the outer membrane. From the sample collected on March 25th, 1949, ten tubes including only resting eggs were separated, their numbers being the following: 2, 2, 3, 3, 5, 5, 7, 9, 10, 10, the mean value being 5.6. The resting eggs on most of the rotifers are not released by the female, but are set free after its death. It has been established of this species that the female produce several resting eggs which find protection in the tube after the mother's death. The very slender and short foot is clearly marked off from the rest of the body. The upper portion has several deep folds and crease, the lower portion has but a few shallow ones. Two muscles appear distinctly through the cuticle. The contractibility of the foot seems not to be very great. Several bends of the foot are, however, possible. Between the foot and the pedunculus there is a joint. The toes could be observed only with difficulty and rarely. On the posterior end of the peduncles there is a disc which assures firm attachment of the organism to the base of the tube. It is almost impossible to sever the body from the mound. It seems that this firm attachment makes possible the frequent, energetic and quick contraction of the body. (ref. ID; 3528)
Male: One male specimen was found by Verga in a sample on Jan. 5th, 1949 collected from under a 20 cm thick ice-layer. It is very active, small in size, and thoroughly transparent. The body is nearly cylindrical, widening somewhat about the middle. Toward the anterior and posterior ends it is slightly bent. The posterior part of the body has a few slight folds and creases but they disappear when the animal swims in an extended attitude. On the anterior end an uninterrupted wreath of cilia is present, the center of the wreath projecting forwards. Both velum and corona are missing. On the edge of the well-developed disc-shaped brain two sickle-shaped eye-spots could distinctly be seen. Slight traces of the infundibulum might be observed. No alimentary canal. The minute contractile vesicle located on the posterior end of the body represents vestiges of the excretory organ. The voluminous testis with its great mass of spermatozoa fills the whole body of the male. Penis is lacking. There is a bunch of hair at the end of the very short and cone-shaped foot. We could not observe the process of copulation, it very like takes place within the tube. (ref. ID; 3528)
Comments
C. volutata are in the closest relation to C. cornuta. However, there are many differences between these two forms, especially as to the structure of the corona and the proportions of the various parts of the body. The dorsal lobe of the corona of C. cornuta is long and has a long, active, fingerlike lateral lobe. Rudiments of such lobe are present on C. volutata, but it envelops the dorsal lobe only halfway both length- and cross- wise. The edge of the coronal disc between the lobes is free from cilia on C. cornuta. The extensive corona of this latter species is nearly as long as the trunk. Its foot is longer than any other parts of the body added together. Its whole length (580-635 µm Collin 1912, p.39) is about twice that of C. volutata. Its two eyes are hardly detectable. The tube - which is attached to various littoral plants - is voluminous, hyaline, and the body is attached to its upper edge. C. volutata might be brought in some sense into interrelationship with the psammobiont C. wiszniewskii too. They are about of equal size, the structure of the corona is similar, however the lateral membrane on the dorsal lobe, the cilia between the lobes on the edge of the disc. And velum are missing on the latter species. Its neck exhibits no wrinkles, its foot is less delicate. The tube -being attached to grains of sand- is gelatinous, being free of any foreign substance, with the exception of a very few particles sticking to the surface. If these three forms were arranged in order of succession, C. wiszniewskii with its simple organisation might be at the end, followed by C. volutata and C. cornuta with the most differentiated organisation, would take the place at the top. (ref. ID; 3528)
Measurements
Length of female, extended, 240-280; length of tubes 350-420 (November-January), 400-800 (March, containing only resting eggs); length of parth. eggs 40-45; length of resting eggs 50-70; length of male 100-105 µm. (ref. ID; 3528)
This species described by Varga in 1938 attached to sand grains in the beaches of Lake Balaton, Hungary. If so, this is the first report of the species since its original description. (ref. ID; 3196)
The long body not sharply separated but gradually narrows and merges into a vigorous foot. Head oblong, cylindrical. Coronal margin with 5 not very highly developed lobes. Dorsal lobe the largest, the others merely broad, low bulges on the coronal margin. Many very long, vibratile setae on the lobes. Between the lobes shorter stiff cilia, bent far outwards, in a position nearly at right-angles to the long axis of the body. Head hyaline, dotted. Foot stout and firm, ending in a short peduncle. Foot wrinkled transversely, wrinkles not forming sharp outline. Proventriculus and stomach large, filled with flagellata. Animal without eyes. Gelatinous tube not large. The few individuals were found on the chitinous remains of an insect, where they formed one side of the gelatinous tube. One surface was formed by chitin, the other by the hyaline gelatin of the animal. The tube was only about half the length of the animal, and was covered with some grains of sand. (ref. ID; 2738)
Measurements
Total length 230; length of body 130; foot 100; width of body 35; corona 38; length of cilia 48 (vibratile) and 10 (stiff) µm. (ref. ID; 2738)
