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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Alaimus

Alaimus De Man, 1880 (ref. ID; 3570, 7637) or 1884 (ref. ID; ?)

Enoplida Filijev, 1929: Family Alaimidae Micoletzky, 1922 (ref. ID; 3570)

Dorylaimida (ref. ID; 7637)

Family Alaimidae (ref. ID; 6182, 6740)

ref. ID; 1663

Amphid obscure. Basal portion of esophagus tapered. (ref. ID; 1663)

ref. ID; 1923

Amphids minute. Freshwater. (ref. ID; 1923)

ref. ID; 3570

Type species

Alaimus primitivus De Man 1880, subsequent designation by De Man in Stiles and Hassal 1905 (ref. ID; 3570)

ref. ID; 6153, 6691, 6859

Bacterivore. (ref. ID; 6153, 6691, 6859)
  1. Alaimus aculeatus Andrassy, 1968 (ref. ID; 3570)
  2. Alaimus acutus Thorne, 1939 (ref. ID; 3570)
  3. Alaimus andrassyi Sabova, 1967 (ref. ID; 3570)
  4. Alaimus arcuatus Thorne, 1939 (ref. ID; 3570)
  5. Alaimus bryophilus (subsp.)
    See; Amphidelus bryophilus (ref. ID; 3570), Amphidelus elegans subsp. bryophilus (ref. ID; 3570)
  6. Alaimus depressus Loof, 1971 (ref. ID; 3570)
  7. Alaimus dhanachandi Choudhary & Jairajpuri, 1984 (ref. ID; 1311)
  8. Alaimus dolichurus De Man, 1876
    See; Amphidelus dolichurus (ref. ID; 2588, 3570)
  9. Alaimus editorus Siddiqi & Husain, 1967 (ref. ID; 3570)
  10. Alaimus elegans De Man, 1921
    See; Amphidelus elegans (ref. ID; 3570)
  11. Alaimus elongatus De Man, 1906 (ref. ID; 3570)
  12. Alaimus filiformis Daday, 1894 (ref. ID; 3570)
  13. Alaimus glissus Thorne, 1939 (ref. ID; 3570)
  14. Alaimus hamulus Siddiqi & Husain, 1967 (ref. ID; 3570, 7637)
  15. Alaimus himatangiensis Yeates, 1967 (ref. ID; 3570)
  16. Alaimus jaulasali Siddiqi & Husain, 1967 (ref. ID; 3570)
  17. Alaimus lemani Stefanski, 1914
    See; Amphidelus lemani (ref. ID; 3570), Amphidelus stefanskii (ref. ID; 3570)
  18. Alaimus leptus Siddiqi & Husain, 1967 (ref. ID; 3570)
  19. Alaimus macer Andrassy, 1958 (ref. ID; 3570)
  20. Alaimus medius Siddiqi & Husain, 1967 (ref. ID; 3570)
  21. Alaimus meyli Andrassy, 1961 (ref. ID; 3570)
  22. Alaimus minor Cobb, 1893 (ref. ID; 3570)
  23. Alaimus modestus Stekhoven & Teunissen, 1938 (ref. ID; 3570)
  24. Alaimus mucronatus Altherr, 1950 (ref. ID; 3570)
  25. Alaimus multipapillatus Wu & Hoeppli, 1929 (ref. ID; 3570)
  26. Alaimus multistriatus Khera, 1973 (ref. ID; 7637 original paper)
  27. Alaimus parvus Thorne, 1939 (ref. ID; 3570)
  28. Alaimus primitivus De Man, 1880 (ref. ID; 1311, 2588, 2592, 3570)
  29. Alaimus proximus Thorne, 1939 (ref. ID; 3570)
  30. Alaimus siddiqii Andrassy, 1970 (ref. ID; 3570)
  31. Alaimus siddiquii Andrassy, 1970 (ref. ID; 1311)
  32. Alaimus similis Thorne, 1939 (ref. ID; 3570)
  33. Alaimus simplex Cobb, 1914 (ref. ID; 3570) reported author and year? (ref. ID; 1923)
    Syn; Aphanolaimus tenuis Daday, 1899 (ref. ID; 3570)
  34. Alaimus striatus Loof, 1964 (ref. ID; 3570, 7637)
  35. Alaimus tasmaniensis Allgen, 1929
    See; Amphidelus tasmaniensis (ref. ID; 3570)
  36. Alaimus tenuis Thorne, 1939 (ref. ID; 3570)
  37. Alaimus thamugadi Maupas, 1900 (ref. ID; 3570)
  38. Alaimus thompsoni Mulk & Coomans, 1979 (ref. ID; 1311)
  39. Alaimus thrixus Siddiqi & Husain, 1967 (ref. ID; 3570)
  40. Alaimus wittmeri Abebe & Coomans, 1995 (ref. ID; 1311 original paper)

Alaimus multistriatus Khera, 1973 (ref. ID; 7637 original paper)

Descriptions

  • Female: Body slender, transparent, tapering in front and behind from near middle of body, ventrally arcuate, more so in posterior region. Tail 158 µm long, about eight times the anal body-diameter, ventrally hooked, regularly tapering except at terminus where it abruptly narrows to a sharp point. Body cuticle thin with 32 longitudinal ridges in the middle of the body extending from anterior end up to anus. The number of ridges gradually reduced to 16 anteriorly and 24 posteriorly. Head rounded at outer (visible) circlet of papillae, continuous with body contour. Lips indistinguishable. Amphid aperture minute, 68 µm from the anterior end (width of body 21 µm at this place), connected directly with sensillae at 81.5 µm from anterior end by slender amphidial tube. Pharynx obscure. Oesophagus 286 µm long, about 2/5 µm long by 24 µm in maximum width. Seven oesophageal glands present Oesophago-intestinal valve thin and disc-like. Intestine broad with moderately broad walls and lumen. Intestinal cells indistinct, granular. Distint pre-rectum absent. Rectum 25 µm long, about one anal body-diameter long. Nerve ring surrounds oesophagus at 127 µm from anterior end, obscure. Excretory pore at 10 µm from anterior end. Ovary single, posterior, reflexed. Oocytes arranged in a single file. No sperm in uterus. Vagina thick, muscular, 18 µm long. Vulva a transverse slit, pre-equatorial in position. Oesophago-vulvar distance 305 µm. (ref. ID; 7637)
  • Male: Male unknown. (ref. ID; 7637)

    Remarks

    The new species described comes close to Alaimus hamulus Siddiqi and Husain, 1967 in the shape of tail and A. striatus Loof, 1964 in the presence of longitudinal ridges on the cuticle. However, it differs from A. hamulus (data of A. hamulus in parentheses) in having a relatively stouter body (a=54 to 64), in the presence of longitudinal ridges on the cuticle, in the anterior location of the excretory pore (25-28 µm from anterior end) and vulva (42-46) and in the value of 'b' in the de Manian formula (4.2-4.8). It differs from A. striatus (data of A. striatus in parentheses) in having a much longer body (0.48 mm), more numerous longitudinal ridges on the cuticle (20), in the shape of tail and in the tail being eight times the anal body-diameter (tail with acute terminus and 4.5 times the anal body-diameter) and in the anterior location of vulva (49). (ref. ID; 7637)

    Type habitat and locality

    Edge of ditch formed by overflow of river. Government Arts College, Lucknow, U.P. (ref. ID; 7637)

    Type materials

  • Holotype: Female, collected on April 13, 1967. Deposited in the National Zoological Collections, Zoological Survey of India, Calcutta. (ref. ID; 7637)
  • Paratypes: Two females on slide no.050-A. (ref. ID; 7637)

    Measurements

  • Holotype (female): L=1.82 mm, a=38, b=5.7, c=11.5, V=35. (ref. ID; 7637)
  • Paratypes (female, n=3): L=1.75-1.9 mm, a=36-39, b=5.5-5.7, c=11-12, V=35-36. (ref. ID; 7637)

    Alaimus wittmeri Abebe & Coomans, 1995 (ref. ID; 1311 original paper)

    Diganosis

    The new species is close to Alaimus siddiquii Andrassy, 1970, in lacking both postrectal intestinal sac and cuticular longitudinal ridges, in having mono-opisthodelphic female reproductive system, a posteriorly enlarging pharynx and a value for the ratio c' higher than 7. But it is different from A. siddiquii in its wider body (a=51.3 as compared to 80 A. siddiquii), in having a shorter tail (tail=186 µm versus 140 µm in A. siddiquii), in the smaller anal body width (=20 µm versus 10 µm in A. siddiquii) and in the more posterior vulval position (V=37.3 versus 33.0 in A. siddiquii). Also, it is close to A. dhanachandi Choudhary & Jairajpuri, 1984, in having seven ventro-median supplements. But, it is differs in having a long and slimmer body [body length=1630 µm (1521-1683), a=51(46-56) as compared to 1080-1180 µm and 44-45 in A. dhanachandi, respectively], in the more posterior position of fusus (=108 µm versus 80-83 µm from the anterior end in A. dhanachandi), in the fewer and more weakly developed ventromedian supplements in males (4-7 as compared to only 7 in A. dhanachandi) and in having a longer tail [tail=186 µm (165-206) versus 72-87 µm in A. dhanachandi]. More over A. dhanachandi was described from a terrestrial habitat. A. wittmeri resembles both A. thompsoni Mulk & Coomans, 1979 and A. primitivus de Man, 1880, in its vulval position (V%=37-39), in having a posteriorly situated fusus, in the absence of pre-vulval uterine sac in lacking a mucro on the tail. But, it differs in having a wider body [a=51(46-56) versus 59-84 in A. thompsoni], in the more anteriorly situated excretory pore (17 µm versus 19-25 µm from the anterior end in A. thompsoni), in the fewer and weakly developed ventromedian supplements in males (4-7 as compared to 6-9 in A. thompsoni), in the longer tail [tail=186 µm (165-206) versus 77-114 in A. thompsoni] and in lacking sexual dimorphism in the lip region (present in A. thompsoni). It differs in having a longer and wider body [body length 1634 µm (1520-1680), a=51(46-56) as compared to 1180-1200 µm and 56-61 in A. primitivus, respectively], in the higher number of ventromedian supplements (4-7 versus 2 or 3 in A. primitivus), in the more anteriorly situated excretory pore (17 µm versus 32-34 µm from the anterior end in A. primitivus) and in having a longer tail [tail=186 µm (165-206) versus 100-120 µm in A. primitivus]. (ref. ID; 1311)

    Descriptions

    Body tapering towards both sides with the posterior part strongly ventrally curved. Cuticle with very fine transverse striae (SEM). Six inner labial papillae on the lip region (SEM). 2-3 µm (SEM) behind these is situated a ring of six outer labial and four cephalic papillae with pores. Lip region rounded and continuous with the rest of the body. Also, body pores are observed just posterior to the lip region. Amphidial opening pore-like; fusus amphidialis observed only in one specimen and situated at about 108 µm from the anterior end. Nerve ring posterior to middle of pharynx. Pharynx anteriorly cylindrical but widening gradually posteriorly. The dorsal and the posterior ventrosublateral nuclei, the former anterior or to latter, occur near the posterior end of the enlarged part of the pharynx. Ventral gland not seen. Excretory pore obscure, around 2.4 lip region widths from the anterior end. Pharyngo-intestinal junction small, the intestine directly fused to the pharynx. Progaster distinctly seen only in two specimens. Intestine with wide lumen, rectum slightly more than one half anal body width long. Tail elongate conoid with sharp tip, slightly more than 14 rectal lengths long. Female reproductive system long, almost one fifth of the total body length; opisthodelphic with single reflexed ovary. A mass of cells in the ovarial tip is followed by fourteen oocytes gradually increasing in size and arranged in one row. Spermatheca clear, filled with closely packed long sperm cells. Vagina a quarter of the corresponding body width and directed posteriorly. Vulva anterior to middle of body. Males shorter and slimmer than females, with a stronger body curvature. The number of ventromedian supplements varies from four to seven, the most posterior one being situated close the cloacal opening. Supplements become weaker as their distance from the cloacal opening increases. Spicules straight, dagger-shaped, nearly as long as the cloaca. (ref. ID; 1311)

    Etymology

    The species is named after the Wittmer's family, which is intimately connected with the recent history of the island. (ref. ID; 1311)

    Measurements

  • Female: Body length 1634+/-57.9(1521-1683) µm, maximum body width 32+/-3.1(28-36) µm, pharyngeal length measured from the anterior end 311+/-18(281-344) µm, tail length 186+/-15.4(165-206) µm, anal body width 20+/-1.9(20-25) µm, lip region width 7+/-0.5(6-7) µm, vagina length 8+/-1.6(7-11) µm, length of reproductive system 309+/-62(226-374) µm, nerve ring from the anterior end 196, excretory pore anterior body end 17, rectal length 13+/-1.5(12-15) µm. (ref. ID; 1311)
  • Male: Body length 1440 (1395-1485) µm, maximum body width 25 (24-26) µm, pharyngeal length measured from the anterior end 275(270-286) µm, tail length 147(119-161) µm, anal body width 20 µm, lip region width 7(6-8) µm, spinneret length 14 µm, number of supplements 4-7, nerve ring from the anterior end 149(141-162) µm. (ref. ID; 1311)