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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Eumonhystera

Order Monhysterida: Family Monhysteridae (ref. ID; 6862)

Family Monhysteridae (ref. ID; 6740)

ref. ID; 6859

Bacterivore. (ref. ID; 6859)
  1. Eumonhystera andrassyi (Biro, 1969) (ref. ID; 7909)
  2. Eumonhystera dispar (ref. ID; 6862)
  3. Eumonhystera filiformis Bastian (ref. ID; 1774)
  4. Eumonhystera longicaudatula (ref. ID; 6940)
  5. Eumonhystera pseudobulbosa (Daday, 1899) Andrassy, 1981 (ref. ID; 1311)
  6. Eumonhystera similis (ref. ID; 6940)
  7. Eumonhystera simplex (ref. ID; 6940)
  8. Eumonhystera tuporis Gagarin, 1991 (ref. ID; 7909 original paper)
  9. Eumonhystera vulgaris (ref. ID; 6940)

Eumonhystera pseudobulbosa (Daday, 1899) Andrassy, 1981 (ref. ID; 1311)

Descriptions

Small animals with slender body, especially in the posterior region. Body almost straight after fixation. Cuticle smooth. Somatic setae not seen. Cephalic setae four, nearly one half lip width long. Cheilostome almost as wide as long, with sclerotized lining. Stoma short and 'V'-shaped and surrounded by pharyngeal tissue. Amphidial fovea circular, about one half corresponding body width, and situated slightly more than two lip widths from the anterior end. Pharynx muscular, anteriorly cylindrical but widening posteriorly. Pharyngeal glandular system with detectable but weakly developed canal system. Nerve ring surrounds the pharynx behind middle. Ventral gland and excretory pore not seen. Cardia as wide as long. Intestine with granulated cells and wide lumen followed by a short rectum, slightly less long than anal body width. Tail very long, 13-17 times rectal length, tapering continuously to three quarters of its length and then becomes almost cylindrical for the remaining part. Tail tip first slightly bulging then ending sharply. Caudal glands difficult to see in most specimens because of the high number of granular bodies in the area. Two of the caudal glands seen in one specimen. Spinneret situated in the bulging part of the tail tip. Female reproductive system generally short, prodelphic, monodelphic with outstretched ovary containing a single row of oocytes. Gonoduct folded. Vagina short. Vulva clear and situated equatorially. (ref. ID; 1311)
  • Male: Male not found. (ref. ID; 1311)

    Measurements

    Body length 334+/-24.3(309-364) µm, maximum body width 12+/-0.8(11-13) µm, pharyngeal length measured from the anterior end 88+/-3.3(84-93) µm, tail length 94+/-4.7(88-100) µm, anal body width 9+/-0.9(7-10) µm, lip region width 6+/-0.7(5-7) µm, distance from vulva to anus 52+/-0.9(51-53) µm, amphid anterior body end 12+/-1.1(10-13) µm, amphid width 2+/-0.4(2-3) µm, corresponding body width 7+/-0.5(6-7) µm, nerve ring from the anterior end 45+/-1.4(44-47) µm, rectal length 7+/-0.7(6-8) µm, length of reproductive system 76+/-6.5(64-78) µm. (ref. ID; 1311)

    Eumonhystera tuporis Gagarin, 1991 (ref. ID; 7909 original paper)

    Diagnosis

    This species is closest to Eumonhystera andrassyi (Biro, 1969), but long and numerous submedial bristles are absent; it is more proportionate (female of E. andrassyi a=21-25), vulva situated closer to the middle of the body (E. andrassyi V-63-67 percent) and the tail relatively longer (in females of E. andrassyi, the tail exceeds the anal diameter of the body 7.7-8.3 times). (ref. ID; 7909)

    Descriptions

    Small, proportionate nematodes. Cuticle smooth and thin, Biocrystals in the body cavity absent. Head width 11-15 µm. Cephalic bristles slender. Their length 6-7 µm, which is approximately 40 percent head width. Openings of the amphids are round, take up 30-40 percent of the width of the body at this level and are situated at a distance equal approximately to 1-1.5 times the diameter of the head from the anterior end of the body. Aggregations of light-sensitive pigment (ocelli) are absent. The body in the region of the proximal end of the esophagus is 2-2.2 times wider than head diameter. The esophagus is subcylindrical, slightly proximally expanded, but does not form a bulb. Its length is 117-156(139) µm. Cardiac glands are well developed, petal-shaped. The rectum is shorter than the anal diameter of the body. The vulva is situated slightly posterior to the middle of the body. Its lips are flat, not sclerotized. A postvulvar cell is absent. In the uterus, there is usually one egg measuring 54-61x21-24 µm. The distance from the vulva to the anus is 1.6 times smaller than the length of the tail. The tail is long, whiplike. Its length is 150-234(195) µm. The spinneret is short, turbinate. Caudal glands are well pronounced. (ref. ID; 7909)

    Examined materials

    Fourteen (female, female) from Ivan'kovo Reservoir (shore, Omutnya, depth 0.5 m, ground-muddy sand, 6.V.1983). Holotype (female) (preparation Ur-13, 1 st.), L=807 µm, a=40.35, b=5.17, c=4.00, V=57.99 percent, c'=15.50. Paratypes: 13 (female, female), L=589-840(740) µm, a=31.61-46.39(38.15), b=4.59-6.62(5.35), c=3.20-4.23(3.82), V=52.73-61.51(57.31) percent, c'=11.00-18.00(15.11). (ref. ID; 7909)

    Type specimens

    Type specimens are deposited in the collection of the Laboratory of Biology and Systematics of Aquatic Organisms of the USSR Academy of Sciences Institute of Inland Waters Biology (Borok village). (ref. ID; 7909)