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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Monommata

Monommata Bartsch, 1870

Class Monogonontaet: Order Ploimida: Family Notommatidae (ref. ID; 6806)

ref. ID; 1663

Toes longer than rest of body, usually unequal in length. Usually in acid waters. (ref. ID; 1663)

ref. ID; 1923

Most easily recognized by the long, unequal toes, but 1 species has equal toes. Formerly Furcularia in part. The weak lorica of Scaridium may be overlooked. (ref. ID; 1923)

ref. ID; 3245

Notommatid rotifers with slender, elongate ovate, spindle-shaped, illoricate body, with a slight constriction behind the mastax, separating the head and abdomen; the foot is very short and obscurely two-jointed; the toes are extremely long, nearly twice the length of the body, and unequal, the right toe long then the left. The corona is slightly oblique and consists of a marginal wreath of cilia with lateral, anricle-like tufts of longer cilia adapted to propulsion; the apical late is unciliated and the buccal field evenly covered with short, close-set cilia; the mouth is somewhat below the center of the corona. The mastax is intermediate between the virgate and forcipate type; the rami are lyrate and the inner margins armed with one or more strong teeth immediately below the mouth opening; the unci have three unequally developed, long, slender, clubbed teeth; the manubria are broad and lamellar the base; the piston is weak and plays only a subordinate part in the operation of the mastax. The retrocerebral organ is imperfectly developed; the sac is ductless and the glands rudimentary or absent; the eyespot is at the posterior end of the ganglion. One of the most interesting results of this survey of the notommatid rotifers is the discovery of the remarkable type of mastax of this genus; a more perfect intermediate of "missing link" between the forcipate and virgate mastax than that of Monommata grandis could hardly be imagined. If only the ventral view were available, it would unhesitatingly be called forcipate; its real affinities become evident at one in the lateral view, showing the curvature of the rami found only in the virgate mastax and also the large basal plate of the manubria. Both are developed as supports for the walls of the pumping type of mastax. However, the changes necessary to transform it into a perfectly good forcipate mastax are small indeed. (ref. ID; 3245)
  1. Monommata actices Myers, 1930 (ref. ID; 1345, 2017, 2269, 2994, 3246 original paper, 3506, 7846)
  2. Monommata aequalis (Ehrenberg, 1832) (ref. ID; 1345, 1847, 2017, 2745, 2757, 3688)
    Syn; Furcularia aequalis Hudson & Gosse, 1886 (ref. ID; 1345, 2757, 3688); Monommata aequalis Eyferth, 1878 (ref. ID; 1345, 3688); Monommata longiseta aequalis Steinecke, 1924 (ref. ID; 3688); Notommata aequalis Ehrenberg, 1832 (ref. ID; 1345, 2017, 3688); Notommata longiseta aequalis Ehrenberg, 1832 (ref. ID; 3688)
  3. Monommata aequalis Eyferth, 1878
    See; Monommata aequalis Ehrenberg, 1832 (ref. ID; 3688), Monommata longiseta (ref. ID; 3245)
  4. Monommata aeschyna Myers, 1930 (ref. ID; 1345, 2017, 2269, 3246 original paper, 3688) reported author and year? (ref. ID; 3411)
  5. Monommata appendiculata Stenroos, 1898 (ref. ID; 1345, 2017, 3246, 3688)
    Syn; Monommata orbis grandis Harring, 1913 (ref. ID; 1345, 3688)
  6. Monommata arndti Remane, 1893 (ref. ID; 1345, 1806) or 1933 (ref. ID; 2017, 2796, 7846) reported year? (ref. ID; 2690)
  7. Monommata astia Myers, 1930 (ref. ID; 1345, 2017, 3246 original paper, 3688) reported year? (ref. ID; 2814)
  8. Monommata caeca Myers, 1930 (ref. ID; 1345, 2017, 2283, 3246 original paper)
  9. Monommata caudata Myers, 1930 (ref. ID; 1345, 2017, 3246 original paper)
  10. Monommata dentata Wulfert, 1940 (ref. ID; 1345, 2017, 2269, 2690, 2932, 3271, 3688) reported year? (ref. ID; 2890, 3403)
  11. Monommata diaphora Myers, 1930 (ref. ID; 1345, 2017, 3246 original paper, 3688)
  12. Monommata dissimile Berzins, 1949 (ref. ID; 2017, 2742 original paper)
  13. Monommata enedra Myers, 1930 (ref. ID; 1345, 2017, 3246 original paper)
  14. Monommata grandis Tessin, 1890 (ref. ID; 1345, 1847, 1923, 2017, 2317, 3245, 3246, 3688) or 1980 (ref. ID; 2810) reported year? (ref. ID; 2890, 3063, 5022)
    Syn; Furcularia longiseta var. grandis Rousselet, 1895 (ref. ID; 1345, 2810, 3245, 3246, 3688); Monommata grandis Harring & Myers, 1924 (ref. ID; 3246); Monommata grandis Levander, 1895 (ref. ID; 3246); Monommata longiseta grandis Weber & Montet, 1918 (ref. ID; 3246, 3688); Monommata longiseta grandis Voigt, 1904 (ref. ID; 3246); Monommata longiseta var. grandis Stenroos, 1898 (ref. ID; 1345, 2810, 3245, 3246, 3688); Monommata maculata Harring & Myers 1924? (ref. ID; 2810); Monommata orbis var. grandis Harring, 1913 (ref. ID; 1345, 3245, 3246); Monommata robusta Berzins, 1949 (ref. ID; 2017)
  15. Monommata hyalina Myers, 1930 (ref. ID; 1345, 2017, 3246 original paper)
  16. Monommata longiseta (O.F. Muller, 1776 (ref. ID; 3126) or 1786 (ref. ID; 1345, 2017, 2757, 2824, 3245, 3275, 3688) reported year? (ref. ID; 2317, 2890)
    Syn; Brachionus orbis Blainville, 1930 (ref. ID; 3688); Cercaria longiseta O.F. Muller, 1776 (ref. ID; 2317, 2757, 3245); Cercaria orbis O.F. Muller, 1776 (ref. ID; 3126, 3688); Furcocerca orbis Lamark, 1815 (ref. ID; 3688); Furcularia aequalis Hudson & Gosse, 1886 (ref. ID; 3245); Furcularia longiseta Eyferth, 1900 (ref. ID; 3688), Hudson & Gosse, 1889 (ref. ID; 3688), Lamarck, 1816 (ref. ID; 1345, 2757, 3245, 3688) or Weber, 1898 (ref. ID; 3688); Monommata aequalis Eyferth, 1878 (ref. ID; 3245); Monommata longiseta Bartsch, 1870 (ref. ID; 1345, 3245, 3688); Monommata orbis Harring, 1913 (ref. ID; 1345, 3245, 3688); Notommata aequalis Ehrenberg, 1832 (ref. ID; 1345, 3245); Notommata longiseta Ehrenberg, 1830 (ref. ID; 1345, 3245); Notommata longiseta aequalis Ehrenberg, 1832 (ref. ID; 3245); Notommata longiseta inaequalis Ehrenberg, 1832 (ref. ID; 3245, 3688); Scaridium longisetum Schoch, 1868 (ref. ID; 1345, 3245) or Schloch, 1868 (ref. ID; 3688); Trichocerca longiseta Blainville, 1830 (ref. ID; 3245), Bory de St. Vincent, 1826 (ref. ID; 3688) or Ehrenberg, 1830 (ref. ID; 3688); Trichoda bicaudata Schrank, 1803 (ref. ID; 3688); Vaginaria brachiura Schrank, 1803 (ref. ID; 3688); Vorticella longiseta O.F. Muller, 1786 (ref. ID; 1345, 2017, 2757, 3245, 3275, 3688)
  17. Monommata longiseta grandis Stenroos, 1898 or Voigt, 1904
    See; Monommata grandis (ref. ID; 1345, 2810, 3245, 3246, 3688)
  18. Monommata maculata Harring & Myers, 1924 (ref. ID; 1345, 1847, 2017, 2834)
  19. Monommata orbis Harring, 1913
    See; Monommata longiseta (ref. ID; 1345, 3245, 3688)
  20. Monommata orbis grandis Harring, 1913
    See; Monommata appendiculata (ref. ID; 1345, 3688), Monommata grandis (ref. ID; 1345, 3245, 3246)
  21. Monommata phoxa Myers, 1930 (ref. ID; 1324, 1345, 2017, 3246 original paper, 3514, 3523, 3688, 7846)
  22. Monommata pseudophoxa Wulfert, 1960 (ref. ID; 2017)
  23. Monommata robusta Berzins, 1949 (ref. ID; 2742 original paper)
    See; Monommata grandis (ref. ID; 2017)
  24. Monommata sphagnicola Berzins, 1949 (ref. ID; 2742 original paper)
  25. Monommata tigris Bartsch, 1870
    See; Trichocerca tigris (ref. ID; 3688)
  26. Monommata viridis Myers, 1937 (ref. ID; 1345, 2017, 2690)

Monommata actices Myers, 1930 (ref. ID; 1345, 2017, 2269, 2994, 3246 original paper, 3506, 7846)

Descriptions

The body of this species is slender and cylindrical, falling away gradually from the neck to the foot. The head segment is long and set off from the abdomen by several strong, dorsal projections and skin folds. The integument is covered with faint longitudinal striations, as are most of the other species of the genus, omitted in the figures for the sake of clarity unless very strong marked. There are pair of large, round, areas in the position of the lateral antennae, one on each side of the abdomen; they may be either deep red or clear. If clear, and their presence is unsuspected, they may be made visible as yellowish spots by intravitam staining with brunswick brown. The foot is obscurely two-jointed and the toes are normal the genus. The dorsal antenna is situated on a papillose prominence and is in the form of a small tubule from which emerges a setigerous tuft of cilia. It is interesting to note that the tubule may be entirely retracted within the integument of the head and its presence unsuspected. The lateral antennae are in the position of the lumber spots. The corona is oblique and the ciliation is normal to the genus. The mastax is minute, virgate and very simple. The fulcrum is long and rod-like, gradually decreasing in lateral view, from the base for about one-third its length. The rami are very slender and lyrate, in ventral view. The alulae are rod-like and divergent. The rami are bent abruptly downward near the middle to an angle of about one hundred degrees. The unci each have two short linear teeth; the ventral pair rest on the rami near the posterior parts of the dorsal portions; the dorsal pair rest on the rami near the middle of the dorsal portions. There are a pair of thin, lamellar supporting plates bounded by the dorsal teeth of the unci and very fine, linear strengthening rods connecting the tips of the rami with the dorsal sides of the manubra. The oesophagus is short. The gastric glands are moderately large and round. There is no constriction between the stomach and the intestine. The foot glands and bladder are small and the ovary is normal. The ganglion is large and saccate. The retrocerebral sac is small and contains numerous bacteroids clustered on the ventral side. There are remnants of a retrocerebral duct that can be traced to the outlets on the corona by intravitam staining with brilliant cresylblau, or brunswick brown. (When there is any doubt about the presence of a retrocerebral sac and ducts, all rotifers should be subjected to intravitam staining, as these organs are often invisible without it). There is a suggestion of confluent salivary glands and the eyespots is at the posterior end of the ganglion. (ref. ID; 3246)

Comments

The presence of the revertile, tubular, dorsal antenna, situated on a prominent papilla, and the red, or clear, lumbar areas, together with the fact that the stomach is generally crowded with green symbiotic zoochlorella, enable this species to be easily determined when seen. (ref. ID; 3246)

Type locality

Monommata actices is not uncommon in permanent bodies of acid water in Atlantic County, N.J. and on Mt. Desert Island, Maine. (ref. ID; 3246)

Measurements

Length of the body 195; length of right toe 210; length of left toe 150; length of trophi 22 µm. (ref. ID; 3246)

Monommata aeschyna Myers, 1930 (ref. ID; 1345, 2017, 2269, 3246 original paper, 3688) reported author and year? (ref. ID; 3411)

Descriptions

The body of this species is elongate and fusiform. The head is separated from the trunk by a slight constriction accented by several skin folds. The body falls away gradually, from a point above the junction of the stomach with the intestine, to the foot which is long and obscurely three-jointed. The toes are normal to the genus. The dorsal antenna is a setigerous tuft on a slightly prominence and the lateral antennae are in the normal position. The corona is ventrally inclined and has the normal disposition of cilia. The mastax is virgate, small and simple. The fulcrum is long and straight with the posterior end slightly recurved, and expanded at the tip for the attachment of the muscles. The rami are triangular, in ventral view, without teeth or denticulations; the dorsal portion forms a right angle with the ventral portion. The alulae are prominent and divergent. The basal portion. The alulae are prominent and divergent. The basal apophysis is large, acutely triangular, and separated from the rami proper by a deep sinus. The manubra are reduced to simple rods, the basal portions being slightly swollen and the posterior portions strongly recurved. On the middle of the dorsal side of each manubrum is a blunt, tooth-like, process which may be the vestigal remnant of the dorsal cell. There is one slender tooth in each uncus that rests on the rami at the point where the anterior and posterior portions form right angles. The oesophagus is short and the gastric glands are small and oval. The stomach and intestine are separated by a slight constriction. The ovary, bladder and foot glands are normal. The ganglion is rather small and saccate. The retrocerebral sac is small, round and ductless, containing densely clustered bacteriods at the distal end. The eye is situated on the ventral side of the ganglion, just forward of the posterior end. (ref. ID; 3246)

Type locality

Monommata aeschyna is rare. It was collected in Cordoy Creek, Atlantic Country, N.J., and in ice ponds at Mansett, Mt. Desert Island Maine. In both cases, this species was found in sphagnum from which it was released by squeezing the water out of the moss into a watch glass. (ref. ID; 3246)

Measurements

Length of the body 150; length of right toe 165; length of left toe 145; length of trophi 25 µm. (ref. ID; 3246)

Monommata appendiculata Stenroos, 1898 (ref. ID; 1345, 2017, 3246, 3688)

Synonym

Monommata orbis grandis Harring, 1913 (ref. ID; 1345, 3688)

Descriptions

The body of this species is stout and cylindrical. The integument is slightly stiffened, finely striated throughout, including the head, making the general shape fairly constant. There is a slight constriction between the head and the abdomen marked by several obscure dorsal skin folds. There is a very prominent tail overhanging the foot, with a well marked constriction at the point where it joins the body. This caudal projection is very characteristic and seems to be of slightly stiffer cuticle than the remainder of the body, as it retains it shape, even in fully contracted individuals. The foot is indistinctly two-jointed and the toes are normal in shape, although they are relatively shorter in length than in most of the species of the genus. The dorsal antenna is a setigerous tuft on a slight prominence and the lateral antennae are in the normal positions. The corona is slightly oblique and the disposition of the cilia is normal to the genus. The mastax is very minute, for such a large animal, and is of the virgate type. The fulcrum is long and, in lateral view, tapers from the base to the posterior end, which is squarely truncate. The rami are triangular in ventral view; the dorsal portions are gradually bent so that near the tips they are almost at right angles to the ventral portions. The alulae are large and divergent. The basal apophysis is acute and acicular. The unci each have two teeth, appearing as one lateral view. The anterior pair are slender and rest on the ventral portions of the rami near their base; the posterior pair are very thin and rod-like, resting on the dorsal portions of the rami near the tips. These teeth are actually the bounding edges of the two very thin, lamellar plates, the dorsal edges of which rest on the lateral edges of the rami. The manubra are short and stout, the basal portions, sub-square and lamellar; the posterior portions rod-like and slightly decurved at the ends. The oesophagus is long. The gastric glands are small and oval. There is slightly constriction between the stomach and the intestine. The bladder is small as are the foot glands. The ovary is normal. The ganglion is large and saccate. The retrocerebral sac is large, containing a few scattered bacteroids. The retrocerebral duct is rudimentary. The eyespot is large and situated on the posterior rend of the ganglion. (ref. ID; 3246)

Comments

In the Synopsis of the Rotifera, Harring gives Monommata appendiculata as a synonym for Monommata orbis grandis Tessin, and in the Rotifer Fauna of Wisconsin, Harring and Myers give it as a synonym for Monommata grandis Tessin. The figure and description of Stenroos are correct, as far as they go, and the species is perfectly valid one. Monommata appendiculata may be recognized at once by its color. The internal organs as well as the integument are always, as far as known, of a yellowish orange tint. This, together with the stiff posterior appendage (so-called tail) and the large, clear retrocerebral sac, together with the minute trophi, are enough to separate it from any other species of the genus. (ref. ID; 3246)

Measurements

Length of the body 225-250; length of right toe 235-250; length of left toe 165-185; length of trophi 25 µm. (ref. ID; 3246)

Monommata arndti Remane, 1893 (ref. ID; 1345, 1806) or 1933 (ref. ID; 2017, 2796, 7846) reported year? (ref. ID; 2690)

Descriptions

Body long, tapering towards posterior end. Toes thin pointed, unequal, longer than body. Base of each toe slightly swollen. Alula of ramus long, pointed. (ref. ID; 1806)

Monommata astia Myers, 1930 (ref. ID; 1345, 2017, 3246 original paper, 3688) reported year? (ref. ID; 2814)

Descriptions

The body of this species is very long, slender and cylindrical; it is slightly swollen over the lumbar region from where it falls rapidly away to the foot. The integument is slightly stiffened and the body shape is fairly constant. The head segment is long and narrow and is separated from the abdomen by a well marked constriction. The foot is obscurely two-jointed and the toes are, relatively, the shorter of any species in the genus. The dorsal antenna is a minute setigerous tuft and the lateral antennae are in the normal position. The corona is squarely truncate for half its depth, then falls away abruptly to almost prone, giving the whole a snout-like appearance. The ciliation is normal to the genus. The mastax is virgate and very simple. The fulcrum is a long, slender, sigmoidal rod. The rami are lyrate in ventral view and approximately at right angles to the fulcrum for their entire length. Each uncus is an excessively thin, lamellar plate, the boundaries of which give the impression of very slender linear teeth. The manubra are reduced to a pair of simple rods, each with a slight thickening near the middle of the ventral side. This is a very primitive pumping apparatus and probably the simplest form of the virgate type of mastax. The oesophagus is short. The gastric glands are very small and oblong oval. There is no constriction between the stomach and the intestine. The ovary, bladder and foot glands are normal to the genus. The ganglion is long and saccate. The retrocerebral sac is small, black and crowded with bacteriods. The eyespot is small, round and situated the posterior end of the ganglion. (ref. ID; 3246)

Comments

It is the smallest species in the genus, very slow and sluggish in movement. The walls of the stomach are generally crowded with symbiotic zoochlorella and, altogether, the species is so characteristic that it is not easily confused with any other. (ref. ID; 3246)

Type locality

Monommata astia is common in permanent bodies of acid water; pH range from 6.0 to 7.0. (ref. ID; 3246)

Measurements

Length of the body 120; length of right toe 80; length of left toe 65; length of trophi 15 µm. (ref. ID; 3246)

Monommata caeca (ref. ID; 1345, 2017, 2283, 3246 original paper)

Descriptions

Typical specimens except for differences in size and slight modifications of the trophi. The manubria are slightly longer and have a greater curvature than American specimens. (ref. ID; 2283)

The body of this species is slender and cylindrical. The integument is flexible and the outline varies according to the state of contraction of the individual. The head segment is relatively short and is separated from the abdomen by several dorsal folds. The abdomen is slightly gibbous dorsally and falls away rapidly from the lumbar region to the foot. The foot is short and obscurely two-jointed. The toes are long and the shape is normal to the genus. The dorsal antenna is a small setigerous tuft on a slight prominence; the lateral antennae are in the normal position. The corona is oblique and the ciliation is normal to the genus. The mastax is virgate. The fulcrum is long and slender, in lateral view, tapering abruptly from the base to the posterior tip. The rami are triangular, in ventral view, and the dorsal portions are bent almost at right angles to the ventral portions. The alulae are divergent, with their bases at right angles to the fulcrum. The unci have two linear teeth which meet at their bases; the ventral pair rest on the rami near the middle; and the dorsal pair rest on the rami near the tips. The area inclosed by the dorsal and ventral teeth of the unci and the lateral edges of the rami are excessively thin lamellar supporting plates. The central cell of each manubrum is shaped like a sigmoidal rod and the basal portion is pyriform. At the posterior end of the dorsal cells of the manubra there are small projecting lobes; the ventral cells are reduced. The oesophagus is short. The gastric glands are oval and elongate. There is no constriction between the stomach and intestine. The bladder is very small as are also the foot glands. The ovary is normal. The ganglion is moderately large and saccate. The retrocerebral sac is large, round and clear, while the duct can be traced for some distance forward. There is no eyespot. (ref. ID; 3246)

Comments

This species cannot be easily confused with any other of the genus, as it is the only one without an eyespot. (ref. ID; 3246)

Type locality

Monommata caeca is rare. It was collected at Bargaintown, Atlantic County, N.J., and in a creek that is the outlet of a pond situated in a depression on the top of a hill, called the Bowl, Mt. Desert Island, Maine. (ref. ID; 3246)

Measurements

Length of body 68; length of right toe 140; length of left toe 106; length of trophi 24 µm. (ref. ID; 2283)

Length of the body 170; length of right toe 210; length of left toe 170; length of trophi 25 µm. (ref. ID; 3246)

Monommata caudata Myers, 1930 (ref. ID; 1345, 2017, 3246 original paper)

Descriptions

The body of this species is elongate and fusiform. The integument is flexible and the shape of the body varies with the state of contraction of the individual. The head segment is separated from the abdomen by a slight constriction. The posterior part of the abdomen falls away suddenly to the base of a well marked, bifid caudal projection. The integument is covered with striations that curve dorsally and meet above the tail. The foot is obscurely three-jointed and the toes are normal to the genus. The dorsal antenna is situated well forward, the small setigerous tuft projects from a minute prominence; the lateral antennae are in the normal position. The corona is oblique and the disposition of the ciliation is normal to the genus. The mastax is virgate. In lateral view, the fulcrum tapers suddenly from a wide base to a long, rod-like, posterior portion. The rami are lyrate, in ventral view, and have two obtuse, angular projections on the inner sides at the point where the ventral teeth of the unci rest. The basal apophysis is long, acute and acicular. The unci each have on apparent linear tooth; they are, in reality, the ventral boundaries of thin lamellar plates resting on the lateral edges of the rami and acting as supports during pumping action. The dorsal boundaries of these plates are marked by linear strengthening rods connecting the dorsal cells of the manubra with the tips of the rami. The manubra are sub-square and lamellae, ending in slightly recurved portions. Near the middle of the central cells of each is a decurved lobe-like projection. The oesophagus is short. The gastric glands are round and minute. There is no constriction between the stomach and the intestine. The bladder, as is usually the case in the genus, is small. The ovary and foot glands are normal. The ganglion is moderately large and saccate. The retrocerebral sac is small and black with densely packed bacteroids. The eye is small and situated at the posterior end of the ganglion. (ref. ID; 3246)

Comments

As it is the only species in the genus with a bifid tail and the characteristic longitudinal striations, all meeting on the dorsal side, it can be confused with any other. (ref. ID; 3246)

Type locality

Monommata caudata is rare, the only location where it has been found being Aunt Bettie's Pond, Mt. Desert Island, Maine. (ref. ID; 3246)

Measurements

Length of the body 180; length of right toe 210; length of left toe 180; length of trophi 22 µm. (ref. ID; 3246)

Monommata diaphora Myers, 1930 (ref. ID; 1345, 2017, 3246 original paper, 3688)

Descriptions

The body of this species is very long and cylindrical; it has a characteristic swelling just above the anterior portion of the stomach that is constant in all individuals. The foot is stout and obscurely two-jointed and the toes are, as usual, very long and normal to the genus. The dorsal antenna is a setigerous tuft on a slight prominence and the lateral antennae are in the normal position. The corona is oblique and the ciliation is normal. The mastax is virgate. The fulcrum is of moderate length and diminishes gradually from the base to the posterior end. There is no basal apophysis. The rami are triangular, in ventral view, without teeth or denticulations; the dorsal portion forms a right angle with the ventral portion, and the alulae are prominent and divergent. The manubra are reduced to simple rods and are attached to the rami by a pair of extremely thin, lamellar plates, that represent the dorsal cells. On the ventral side of each manubrum, at the point where a dorsal change of direction occurs, there is a spur resembling a tooth. There is one slender sigmoidal tooth in each uncus, resting on each ramus near the middle of the anterior portion. The oesophagus is short and the gastric glands very small and round. The stomach and intestine are separated by a slight constriction. The bladder is very small and the ovary and foot glands are normal. The ganglion is large and saccate. The retrocerebral sac is crowded with bacteroids and has a broken duct with outlets on the face of the corona. There are a large pair of confluent salivary glands, with contained nuclei, attached to the posterior portion of the mastax. The eye is on the ventral side of the ganglion near the posterior end and there is a small refractive globule just in front of the red pigment. (ref. ID; 3246)

Comments

Superficially, it resembles Monommata enedra, but is easily distinguished from it by the presence of a retrocerebral sac with its broken duct; the confluent salivary glands; the absence of a prominent tail and the differences in the trophi. (ref. ID; 3246)

Type locality

Monommata diaphora is fairly common in acid water of the littoral region of ponds and lakes in Atlantic County, N.J. and Mt. Desert Island, Maine. (ref. ID; 3246)

Measurements

Length of the body 225; length of right toe 260; length of left toe 225; length of trophi 25 µm. (ref. ID; 3246)

Monommata enedra Myers, 1930 (ref. ID; 1345, 2017, 3246 original paper)

Descriptions

The body of this species is elongate and cylindrical. The integument is slightly stiffened and the shape is fairly constant. The head is separated from the body by a distinct constriction with several marked dorsal skin folds. There is a prominent tail overhanging the foot and there are several wrinkles at the point where the body and tail meet. The foot is obscurely two-jointed and the toes are normal to the genus. The corona is oblique and the disposition of the cilia is the same as in the other species of the genus. The virgate mastax is very small and simple. The fulcrum is somewhat sigmoidal, long, and slender, tapering gradually towards the posterior end. The rami are triangular, in ventral view, without teeth or denticules; the dorsal portion of each forms almost a right angle with the ventral portion and the alulae are prominent and divergent. The manubra are reduced to simple rods; there is a dorsal change of direction induced to simple rods; there is a dorsal change of direction in each, forming an obtuse angle, near the posterior end. The bases of the manubra are produced into very fine rods that rest on the rami near the middle. There are a pair of excessively thin lamellar plates connecting the dorsal portion of the rami with the posterior two-thirds of the manubra. The oesophagnus is long and the gastric glands are small and oval in shape. The intestine is clear and slightly constricted at the point of junction with the stomach. The ovary, bladder and foot glands are normal. The dorsal antenna is a small setigerous tuft and is not papillose as in some of the other species of the genus. The lateral antennae are normal. The ganglion is large and saccate. There is no apparent retrocerebral sac. The eyespot is large and dark, situated on the posterior end of the ganglion; it has a small globule of high refractive index just in front of the pigment. There are no subcerebral glands. (ref. ID; 3246)

Comments

It is readily distinguished from the other species of the genus by the absence of a retrocerebral sac; the very small and simple mastax; the refractive globule in front of the eye-pigment, together with the presence of a prominent tail. (ref. ID; 3246)

Type locality

Monommata enedra is rare, having been found only in the acid waters of Aunt Bettie's Pond, Mt. Desert Island, Maine, and Lenapi Lake, Atlantic Country, New Jersey. (ref. ID; 3246)

Measurements

Length of the body 150; length of right toe 210; length of left toe 155; length of trophi 25 µm. (ref. ID; 3246)

Monommata grandis Tessin, 1890 (ref. ID; 1345, 1847, 1923, 2017, 2317, 3245, 3246, 3688) or 1980 (ref. ID; 2810) reported year? (ref. ID; 2890, 3063, 5022)

Synonym

Furcularia longiseta var. grandis Rousselet, 1895 (ref. ID; 1345, 2810, 3245, 3246, 3688); Monommata grandis Harring & Myers, 1924 (ref. ID; 3246); Monommata grandis Levander, 1895 (ref. ID; 3246); Monommata longiseta grandis Weber & Montet, 1918 (ref. ID; 3246); Monommata longiseta grandis Voigt, 1904 (ref. ID; 3246, 3688); Monommata longiseta var. grandis Stenroos, 1898 (ref. ID; 1345, 2810, 3245, 3246, 3688); Monommata maculata Harring & Myers 1924? (ref. ID; 2810); Monommata orbis var. grandis Harring, 1913 (ref. ID; 1345, 3245, 3246); Monommata robusta Berzins, 1949 (ref. ID; 2017)

Descriptions

The body of this species is moderately slender, elongate ovate and spindle-shaped; its greatest width is less than one third of the length. The integument is rather flexible and the outline is quite constant. The body is moderately transparent. The head segment is moderately large and the width nearly equal to the length. It is separated from the abdomen by a well marked constriction. The abdomen is elongate and ovate, distinctly gibbous dorsally and rounded posteriorly; the integument is marked with very closely spaced, unbroken longitudinal striae, acute-angled at the bottom of the grooves and the top of the ridges. The foot is short, stout and obscurely two-jointed. The toes are extremely long and unequal; their length, both absolute and relative, is highly variable; the left toe is always shorter than the right, the difference varying between one third and one fifth of the length of the right toe. The basal portion of the toes, from one third to one half of its length, is very nearly straight for the greater part of its length; this is followed by a tapering section, which passes into the very nearly cylindrical, extremely slender posterior portion, which is from one half to two thirds of the entire length. The right toe is straight and in the axis of the body; the left toe curves slightly upwards and to the left. The dorsal antenna is a small setigerous papilla in the normal position; the lateral antennae are on the posterior fourth of the body. The corona is very slightly oblique and consists of a marginal wreath of cilia with lateral, auricle-like tufts of longer cilia for propulsion; the apical plate is unciliated and the buccal field evenly covered with short, close-set cilia. The mastax belongs to a type intermediate between the virgate and the forcipate, the piston playing but a very subordinate role in its function. The fulcrum is rather short and very broad at the base, tapering rapidly to the blunt posterior end. The rami are broadly triangular at the base and the posterior portion lyrate; the basal apophysis is abnormally large, somewhat curved and separated from the rami proper by a deep, rounded sinus. The inner margins of the rami are equipped with a unique and complicated dental armature. The teeth are naturally divisible into three groups; ventral, oral and posterior. The ventral group consists of 12-14 comblike teeth; Their length increases gradually to a point somewhat beyond mid-length, decreasing from there towards the oral group. This consists of four extremely large, stout, slightly curved and acutely pointed, interlocking teeth; the relative length and development of the individual teeth is somewhat variable, especially in the case of the second and third tooth on each side. The posterior group consists of three long, slender, acutely pointed, interlocking needle-like teeth in each ramus. Each uncus has three long, slender, unequal teeth, clubbed at the tips; two rest on the rami at the base of the comb-like teeth and one on the posterior end, beyond the oral group of teeth. In the right uncus the ventral tooth is largest and the second somewhat smaller; in the left uncus the ventral tooth is relatively small and the second as large as the right ventral. The basal portion of the manubria is broad and plate-like, the posterior rod-like and decurved at the end. The piston is relatively small and weak. The oesophagus is short. The gastric glands are rather small and rounded. There is no constriction between the stomach and intestine. The ovary and bladder are normal. The foot glands are small and pyriform. The ganglion is large and saccate. The retrocerebral sac is fairly large and pyriform; it is usually crowded with bacteroids and opaque to transmitted light. The duct can not be trace beyond the dorsal antenna; subcerebral glands are not present. The eyespot is at the posterior end of the ganglion. (ref. ID; 3245)

The body of this species elongate and fusiform; the integument is slightly stiffened and the outline is fairly constant in shape. The rare two round, red, pigment spots in the portion of the lateral antennae that are very characteristic, the function of which is unknown. The foot is obscurely two-jointed and the toes often attain the greatest length development of any species in the genus, although they may sometimes be relatively short. The dorsal antenna is situated on a papillose prominence of medium size and the lateral antennae in the normal position. The corona is oblique and the disposition of the cilia is normal to the genus. The mastax is intermediate between the virgate and forcipate types. The fulcrum is about equal to the rami in length, very broad at the base, tapering to a small, blunt posterior end. The medial portions of the rami are extended laterally into two pairs of very thin lamellae; the basal apophysis is large separated from the rami proper by a deep sinus; the alulae are large and at right angles to the fulcrum. The inner margins of the rami are equipped with ventral and oral teeth. The ventral group consists of many, twenty-five or more, comb-like of the denticules on each inner margin; the oral group consist of two pairs, each having four long, slightly curved, opposing teeth joined to strong lamellar plates that have their origin on the ventral sides of the rami. There are no dorsal teeth to the rami. Each uncus has two teeth; the first, or ventral opposing pair, are broad and lamellae, with the truncate tips divided into five small, blunt, tooth-like projections; the dorsal pair are slender and rod-like. The basal portion of the manubra is broad and lamellar; the dorsal cell being rectangular and half the length of the ventral cell; the median cell is rod-like and decurved near the tip. The oesophagus is short. The gastric glands are elongate and oblong with their longitudinal axis pointing dorso-ventrally. There is no constriction between the stomach and intestine. The ovary is very long and the bladder is small. The foot glands are small and pyriform. The toes vary in size with the individual, being extremely long in some specimens and not much longer than the body in others. The ganglion is large and saccate. The retrocerebral sac is small and contains massed bacteriods. The duct is prominent and continues with out interruption to the outlets on the face of the corona. There seem to be no subcerebral glands. There are confluent salivary glands attached to the posterior part of the mastax, each containing several nuclei. The eyespot is slightly ventral, situated near the posterior tip of the ganglion. (ref. ID; 3246)

Comments

Its nearest relative is Monommata maculata, from which it is easily separated by the differences in the trophi, the extension to the outlets to the face of the corona, of the retrocerebral duct; the presence of confluent salivary glands and the two round, red, areas in the position of the lateral antennae. At this is evidently the animal described by Tessin, a new name will have to be proposed for Monommata grandis, redescribed by Harring and Myers in 1924. Therefore, that species is now renamed Monommata maculata, new species, Harring & Myers. (ref. ID; 3246)

Measurements

Length of body 150; length of toes 274 and 280 µm. (ref. ID; 2317)

Greatest length 680; body 210; right toe 470; trophi 26 µm. (ref. ID; 3245)

Length of the body 190-240; length of right toe 210-400; length of left toe 150-300; length of trophi 35 µm. (ref. ID; 3246)

Monommata hyalina Myers, 1930 (ref. ID; 1345, 2017, 3246 original paper)

Descriptions

The body of this species is large, stout and cylindrical transparent and milky in color; its bulk being greater than that of any other species in the genus. The integument flexible and the outline varies with the state of contraction of the individual. The head segment is large its depth being about equal to its length. The foot is short, stout and obscurely two-jointed. The toes, as usual in this genus, are very long, the left being much shorter than the right; the basal portions are stout and tapering, passing gradually into the cylindrical, slender posterior portions. The dorsal antenna is situated on a pronounced, setigerous prominence in the normal position; the minute lateral antennae are on the posterior fourth of the body, one on each side. The corona is oblique and the posterior half is nearly ventral, being prolonged into a very prominent chin-like process. The ciliation consists of a marginal wreath with lateral, auricle-like tufts of longer cilia adapted for propulsion. The apical area is unciliated and the buccal plate evenly covered with short, close-set cilia. The mastax is very large and modified virgate in type. The hypopharynx is very prominent, strong and transversely striated. The fulcrum is long, stout, and swollen in the middle portion; it is longitudinal striated, the posterior end being recurved and serrate. The rami are roughly triangular, in ventral view, and without a basal apophysis. At the point of articulation on the inner side of the right ramus, there is denticulate comb-like process having eight or ten teeth. There are no other teeth on the inner margins of the rami. Each uncus has a long, slender, sigmoidal tooth, clubbed at the tip. The basal portions of the manubra are sub-orbicular and plate-like; the posterior portions, rod-like ending with the tips strongly recurved and uncinate. A pair of slender, clavate rods are embedded in the walls of the mastax below the posterior edge of the rami and assist in support during pumping action. The oesophagus is short. The gastric glands are very small and oval. There is a strong constriction between the clear intestine and the stomach. The ovary and bladder are normal. The foot glands are rather small and pyriform. The ganglion is large and saccate. The retrocerebral sac is small; the contained bacteroids rendering it more or less opaque to transmitted light. The duct could not be traced beyond the sac, nor could subcerebral glands be found. The eye-spot is large and situated on the posterior end of the ganglion. (ref. ID; 3246)

Type locality

Monommata hyalina is fairly common among aquatic plants in permanent bodies of acid water (pH 6.4-6.8), on Mt. Desert Island, Maine, and Atlantic Country, New Jersey. (ref. ID; 3246)

Measurements

Length of the body 300; length of right toe 350; length of left toe 250; length of trophi 70 µm. (ref. ID; 3246)

Monommata longiseta (O.F. Muller, 1776 (ref. ID; 3126) or 1786 (ref. ID; 1345, 2017, 2757, 2824, 3245, 3275, 3688) or reported year? (ref. ID; 2317, 2890)

Synonym

Brachionus orbis Blainville, 1930 (ref. ID; 3688); Cercaria longiseta O.F. Muller, 1776 (ref. ID; 2317, 2757, 3245); Cercaria orbis O.F. Muller, 1776 (ref. ID; 3126, 3688); Furcocerca orbis Lamark, 1815 (ref. ID; 3688); Furcularia aequalis Hudson & Gosse, 1886 (ref. ID; 3245); Furcularia longiseta Eyferth, 1900 (ref. ID; 3688), Hudson & Gosse, 1889 (ref. ID; 3688), Lamarck, 1816 (ref. ID; 1345, 2757, 3245, 3688) or Weber, 1898 (ref. ID; 3688); Monommata aequalis Eyferth, 1878 (ref. ID; 3245); Monommata longiseta Bartsch, 1870 (ref. ID; 1345, 3245, 3688); Monommata orbis Harring, 1913 (ref. ID; 1345, 3245, 3688); Notommata aequalis Ehrenberg, 1832 (ref. ID; 1345, 3245); Notommata longiseta Ehrenberg, 1830 (ref. ID; 1345, 3245); Notommata longiseta aequalis Ehrenberg, 1832 (ref. ID; 3245); Notommata longiseta inaequalis Ehrenberg, 1832 (ref. ID; 3245, 3688); Scaridium longisetum Schoch, 1868 (ref. ID; 1345, 3245) or Schloch, 1868 (ref. ID; 3688); Trichocerca longiseta Blainville, 1830 (ref. ID; 3245), Bory de St. Vincent, 1826 (ref. ID; 3688) or Ehrenberg, 1830 (ref. ID; 3688); Trichoda bicaudata Schrank, 1803 (ref. ID; 3688); Vaginaria brachiura Schrank, 1803 (ref. ID; 3688); Vorticella longiseta O.F. Muller, 1786 (ref. ID; 1345, 2017, 2757, 3245, 3275, 3688)

Descriptions

The body of this species is slender, elongate ovate and spindle-shaped; its greatest width is less than one fourth of the length. The integument is very flexible, but the outline is fairly constant. The entire body is very transparent. The head segment is relatively short and broad; the length slightly greater than the width. It is separated from the abdomen by a well marked constriction. The abdomen is elongate and ovate, slightly gibbous dorsally and rounded posteriorly; the integument is covered with minute, interrupted, very closely spaced longitudinal striae. The foot is short, stout and obscurely two-jointed. The toes are extremely long and unequal; the left toe is always shorter than the right, but the relative length is variable, the usual proportion being four to five, but may be as much as one to two and individuals are occasionally found with nearly equal toes. The basal portion of the toes is fairly stout and very nearly cylindric, tapering gradually to the cylindrical, extremely slender posterior portion, which is fully half the length of the entire toe. The right toe is virtually straight and in the axis of the body; the left toe curves slightly upwards and to the left. The dorsal antenna is a small setigerous papilla in the normal position the lateral antennae are on the posterior fourth of the body. The corona is very slightly oblique and consists of a marginal wreath of cilia with lateral, auricle-like tufts of longer cilia for propulsion; the apical plate is unciliated and the buccal field evenly covered with short, close-set cilia. The mastax is of a modified virgate type. The fulcrum is long and slender and tapers gradually towards the posterior end. The rami are triangular at the base and bent near mid-length at an approximately right angle; the dorsal portion is long, slender, tapering and slightly incurved. Each ramus has at the angle a long, slender tooth, interlocking with its mate on the opposite side. The right uncus has three very long, slender teeth, the posterior resting on the tip of the ramus, the two anterior on the ramus just below the inner tooth; the left uncus has two teeth, one resting on the posterior tip of the ramus and the other just below the inner tooth. The manubria are broad and lamellar, ending in a rod-shaped posterior portion, slightly recurved at the end. The piston is large, but apparently not very powerful. The oesophagus is rather short. The gastric glands are small and rounded. There is no constriction between stomach and intestine. The ovary and bladder are normal. The foot glands are very small and pyriform. The ganglion is moderately large and saccate. The retrocerebral sac is small and apparently ductless; it contains a small number of transparent, globular bodies and can not be stained. Near mid-length of the ganglion are two small, rounded masses representing the subcerebral glands, indicated in the figures, but invisible without intra-vitam staining. The eyespot is at the posterior end of the ganglion. (ref. ID; 3245)

Comments

Muller's Cercaria orbis was undoubtedly a contracted Monommata. Accepting as fact the frequently asserted identity of the two "varieties" in every respect except size, the species was listed as Monommata orbis by Harring in the Synopsis of the Rotatoria in accordance with accepted rules of nomenclature. However, it is very evident that the genus includes two perfectly distinct species and it is not now possible to refer C. orbis definitely to one or the other. For this reason we have used the later name longiseta, as it unquestionably belongs to the smaller species. (ref. ID; 3245)

Measurements

Length of body 100; length of toes 125 and 150 µm. (ref. ID; 2317)

Length of body 70; toes 130 and 100 µm. (ref. ID; 3126)

Total length 200-250; length of body 75-95; length of right toe 125-155; left toe two thirds to four fifths of right toe; trophi 18 µm. (ref. ID; 3245)

Body length 100-115 (contracted specimens); length of right toe 200-250; length of left toe 150-195 µm. (ref. ID; 3275)

Monommata maculata Harring & Myers, 1924 (ref. ID; 1345, 1847, 2017, 2834)

Descriptions

Jaws: Fulcrum frontal short bacilliform, lateral board-like. Inner edge of rami with three groups of teeth: middle oral group four big teeth each, dorsal with three small teeth each. Manubria bend at the end with a stout lamella. (ref. ID; 2834)

Measurements

Total length -680; right toe 340-470; left toe 270-410; length of jaws 26-36 µm. (ref. ID; 2834)

Monommata phoxa Myers, 1930 (ref. ID; 1324, 1345, 2017, 3246 original paper, 3514, 3523, 3688, 7846)

Descriptions

The body of this species is long and cylindrical; its shape varies with the state of contraction of the individual, as the integument is quite flexible. The head segment is moderately long and separated from the abdomen by a slight constriction with several dorsal skin folds. The foot is obscurely two-jointed and the toes are normal to the genus. The dorsal antenna is a minute, setigerous tuft, emerging from a small prominence; the lateral antennae are in the usual position and normal to the genus. The corona is oblique and the ciliation is normal. The mastax is virgate. The fulcrum is very long, expanded and serrate at the posterior end for the attachment of the hypopharynx. The rami are bent at nearly right angles near the middle and are lyrate, in ventral view. The alulae are large, triangular, and at right angles to the fulcrum. Each uncus has a cluster of five or six linear teeth arising from a common base and resting on the ventral portions of the rami near their points of junction with the fulcrum. There are a pair of linear rods running from the tips of the rami, appearing to be continuations of the bases of the two clusters of teeth referred to above. These rods mark the limits of two very thin, lamellar supporting plates that rest on the lateral sides of the rami. The basal portions of the manubra are rectangular; the dorsal cells are large and each has a decurved lobe-like projection at the posterior angle. The posterior ends of the middle cells are expanded and slightly decurved. There are no ventral cells. The oesophagus is short. The gastric glands are very small and round. There is a well marked constriction between the stomach and the intestine. The bladder and foot glands are small and the ovary is normal. The ganglion is small and saccate. The retrocerebral sac is small and contains clustered bacteroids; the duct may be traced for some distance forward. The eye is small and situated on the ventral side of the ganglion near the posterior end. (ref. ID; 3246)

Comments

The characters are rather negative and the trophi should be examined in order to determined the species. (ref. ID; 3246)

Type locality

Monommata phoxa is evidently rare. It as collected in an acid pond near English Creek, Atlantic County N.J. (ref. ID; 3246)

Measurements

Length of the body 150; length of right toe 190; length of left toe 140; length of trophi 35 µm. (ref. ID; 3246)