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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Plectus

Plectus Bastian, 1865 (ref. ID; 3571, 7244)

Subphylum Torquentia: Order Araeolaimida: Suborder Araeolaimina: Family Plectidae (ref. ID; 1276)

Araeolaimida De Coninck & Stekhoven, 1933: Family Plectidae Orley, 1880: Subfamily Plectinae Orley, 1880 (ref. ID; 3571)

Order Chromadorida: Family Plectidae (ref. ID; 6862)

Family Plectidae (ref. ID; 6168, 6182, 6740)

ref. ID; 1663

Head not offset; stoma without teeth. (ref. ID; 1663)

ref. ID; 1795, 6153, 6155, 6691, 6859

Bacterial feeder. (ref. ID; 1795, 6153, 6155, 6691, 6859)

ref. ID; 1923

Stoma narrowed somewhat posteriad; supplements papilloid. (Aquatic; a large genus, about 50 species) (ref. ID; 1923)

ref. ID; 3571

Type species

Plectus parietinus Bastian 1865 (ref. ID; 3571)
  1. Plectus aberrans Kreis, 1930 (ref. ID; 3571)
  2. Plectus acuminatus Bastian, 1865 (ref. ID; 3571, 7244) reported year? (ref. ID; 1756) reported author and year? (ref. ID; 7080)
    Syn; Plectus communis Butschli, 1873 (ref. ID; 3571)
  3. Plectus acuticaudatus Truskova, 1976 (ref. ID; 7244)
  4. Plectus africanus Daday, 1908
    See; Plectus cirratus (ref. ID; 3571)
  5. Plectus agilior Cobb, 1898 (ref. ID; 3571)
  6. Plectus amorphotelus Ebsary, 1985 (ref. ID; 7244 original paper)
  7. Plectus amphidiscatus Filipjev, 1929 (ref. ID; 3571)
  8. Plectus andrassyi (Andrassy, 1963) Timm, 1971 (ref. ID; 7244) or Timm, 1971 (ref. ID; 881, 3571)
    Syn; Plectus globilabiatus Andrassy, 1963 (ref. ID; 881, 3571)
  9. Plectus annulatus Maggenti, 1961 (ref. ID; 3571, 7244)
  10. Plectus antarcticus De Man, 1904 (ref. ID; 3571, 7244)
    Syn; Plectus murrayi Yeates, 1970 (ref. ID; 3571)
  11. Plectus aquatilis (ref. ID; 6940, 7080)
  12. Plectus arctus Truskova, 1976 (ref. ID; 7244)
  13. Plectus armatus Butschli, 1873 (ref. ID; 3571, 7244)
    Syn; Cyatholaimus styriacus Micoletzky, 1922 (ref. ID; 3571)
  14. Plectus assimilis Butschli, 1873 (ref. ID; 2588, 3571, 7244)
  15. Plectus auriculatus Butschli, 1873
    See; Tylocephalus auriculatus (ref. ID; 3571)
  16. Plectus auriculatus De Man
    See; Plectus otophorus (ref. ID; 2592)
  17. Plectus australis (subsp.) Cobb, 1898
    See; Plectus parietinus (ref. ID; 3571)
  18. Plectus belgicae De Man, 1904
    See; Plectus antarcticus (ref. ID; 3571), Plectus parvus (ref. ID; 3571)
  19. Plectus blanci Hofmanner in Hofmanner & Menzel, 1914
    See; Anaplectus granulosus (ref. ID; 3571)
  20. Plectus cancellatus Zullini, 1978 (ref. ID; 7244 redescribed paper)
  21. Plectus cephalatus Cobb, 1893
    See; Tylocephalus cephalatus (ref. ID; 3571)
  22. Plectus chengmohliangi Hoeppli & Chu, 1932
    See; Plectus longicaudatus (ref. ID; 3571)
  23. Plectus cirratus Bastian, 1865 (ref. ID; 1756, 2588, 2592, 3439, 3571, 7244)
    Syn; Plectus africanus Daday, 1908 (ref. ID; 3571)
  24. Plectus communis Butschli, 1873 (ref. ID; 2588, 2592)
    See; Plectus acuminatus (ref. ID; 3571), Plectus parvus (ref. ID; 3571)
  25. Plectus cornus Maggenti, 1961 (ref. ID; 3571, 7244)
  26. Plectus demani Orley, 1880 (ref. ID; 3571)
  27. Plectus effilatus Stekhoven & Mawson, 1954 (ref. ID; 3571)
  28. Plectus elongatus Maggenti, 1961 (ref. ID; 3571, 7244)
  29. Plectus elymi Allgen, 1949
    See; Haliplectus bibulbosus (ref. ID; 3571)
  30. Plectus eurycercus Massey, 1964 (ref. ID; 7244)
  31. Plectus exinocaudatus Truskova, 1976 (ref. ID; 7244)
  32. Plectus falklandiae Allgen, 1959 (ref. ID; 3571)
  33. Plectus fausti Kreis, 1930
    See; Wilsonema fausti (ref. ID; 3571)
  34. Plectus frigophilis Kirjanova, 1958 (ref. ID; 7244)
  35. Plectus frigophilus Kiryanova, 1958 (ref. ID; 3571)
  36. Plectus fusiformis Bastian, 1865
    See; Plectus parietinus (ref. ID; 3571)
  37. Plectus geophilis de Man, 1880 (ref. ID; 7244)
  38. Plectus geophilus De Man, 1884 (ref. ID; 2592) or 1880 (ref. ID; 3571)
  39. Plectus gisleni Allgen, 1951 (ref. ID; 3571)
  40. Plectus globilabiatus Andrassy, 1963
    See; Plectus andrassyi (ref. ID; 881, 3571)
  41. Plectus globilabiatus Kiryanova, 1958 (ref. ID; 3571)
  42. Plectus globocephalus Mulk & Coomans, 1978 (ref. ID; 7244)
  43. Plectus gracilis Truskova (ref. ID; 7244)
  44. Plectus grahami Allgen, 1951 (ref. ID; 3571)
  45. Plectus grandepapillatus (subsp.) Ditlevsen, 1928
    See; Anaplectus granulosus subsp. grandepapillatus (ref. ID; 3571)
  46. Plectus granulosus Bastian, 1865 (ref. ID; 2588)
    See; Anaplectus granulosus (ref. ID; 3571)
  47. Plectus hawaiiensis Cobb, 1906
    See; Plectus parietinus (ref. ID; 3571)
  48. Plectus indicus Khera, 1972 (ref. ID; 7244)
  49. Plectus inquirendus Andrassy, 1958 (ref. ID; 3571, 7244)
  50. Plectus insignis Cobb, 1893 (ref. ID; 3571)
  51. Plectus intermedius Cobb, 1893
    See; Plectus parietinus (ref. ID; 3571)
  52. Plectus intorticaudatus Truskova, 1976 (ref. ID; 7244)
  53. Plectus kenyanus Allgen, 1952
    See; Plectus longicaudatus (ref. ID; 3571)
  54. Plectus longicaudatus Butschli, 1873 (ref. ID; 2588, 3571, 7244)
    Syn; Plectus chengmohliangi Hoeppli & Chu, 1932 (ref. ID; 3571); Plectus kenyanus Allgen, 1952 (ref. ID; 3571); Plectus meridionalis Steiner, 1916 (ref. ID; 3571)
  55. Plectus longicaudatus subsp. opisthocirculus Andrassy, 1952
    See; Plectus parvus (ref. ID; 3571)
  56. Plectus makrodemas Massey, 1964 (ref. ID; 7244)
  57. Plectus meridionalis Steiner, 1916
    See; Plectus longicaudatus (ref. ID; 3571)
  58. Plectus minimus Cobb, 1893 (ref. ID; 3571)
  59. Plectus minor Novicova & Gagarin, 1971 (ref. ID; 7244)
  60. Plectus multitubiferus Imamura, 1931
    See; Paraplectonema multitubiferum (ref. ID; 3571)
  61. Plectus murrayi Yeates, 1970
    See; Plectus antarcticus (ref. ID; 3571)
  62. Plectus naticochensis Steiner, 1930
    See; Plectus parietinus (ref. ID; 3571)
  63. Plectus obtusicaudatus Daday, 1899 (ref. ID; 3571)
  64. Plectus opisthocirculus
    See; Plectus longicaudatus subsp. opisthocirculus (ref. ID; 3571), Plectus parvus (ref. ID; 3571)
  65. Plectus ornatus Butschli, 1873
    See; Plectus parietinus (ref. ID; 3571)
  66. Plectus otophorus De Man, 1880 (ref. ID; 3571) or 1884 (ref. ID; 2592)
    See; Wilsonema otophorum (ref. ID; 3571)
    Syn; Plectus auriculatus De Man (ref. ID; 2592)
  67. Plectus palustris De Man, 1880 (ref. ID; 881, 1749, 3571, 7244)
  68. Plectus paracommunis Hoeppli, 1926
    See; Plectus parvus (ref. ID; 3571)
  69. Plectus paraguayensis Kreis, 1932 (ref. ID; 3571)
  70. Plectus parainquirendus Gagarin, 1971 (ref. ID; 3571, 7244)
  71. Plectus parietinus Bastian, 1865 (ref. ID; 1756, 2592, 3571, 7244)
    Syn; Plectus fusiformis Bastian, 1865 (ref. ID; 3571); Plectus hawaiiensis Cobb, 1906 (ref. ID; 3571); Plectus intermedius Cobb, 1893 (ref. ID; 3571); Plectus naticochensis Steiner, 1920 (ref. ID; 3571); Plectus ornatus Butschli, 1873 (ref. ID; 3571); Plectus patagonicus De Man, 1904 (ref. ID; 3571); Plectus pusteri Fuchs, 1930 (ref. ID; 3571); Plectus velox Bastian, 1865 (ref. ID; 3571)
  72. Plectus parvus Bastian, 1865 (ref. ID; 881, 1723, 2588, 3571)
    Syn; Plectus belgicae De Man, 1904 (ref. ID; 3571); Plectus opisthocirculus Andrassy, 1952 (ref. ID; 3571); Plectus paracommunis Hoeppli, 1926 (ref. ID; 3571); Plectus potamogeti W. Schneider, 1937 (ref. ID; 3571); Rhabdolaimus balatonicus Daday, 1894 (ref. ID; 3571)
  73. Plectus patagonicus De Man, 1904
    See; Plectus parietinus (ref. ID; 3571)
  74. Plectus pedunculatus Hofmanner, 1913
    See; Paraplectonema pedunculatum (ref. ID; 3571)
  75. Plectus potamogeti W. Schneider, 1937
    See; Plectus parvus (ref. ID; 3571)
  76. Plectus pusillus Cobb, 1893 (ref. ID; 3571)
  77. Plectus pusteri Fuchs, 1930
    See; Plectus parietinus (ref. ID; 3571)
  78. Plectus raabei Brzeski, 1961 (ref. ID; 3571)
  79. Plectus rhizophilus De Man, 1880 (ref. ID; 2588, 3571, 7244) or 1884 (ref. ID; 2592)
  80. Plectus rivalis (Dujardin, 1845) Bastian, 1865 (ref. ID; 3571)
    Syn; Enoplus rivalis Dujardin, 1845 (ref. ID; 3571)
  81. Plectus sambesii Micoletzky, 1915 (ref. ID; 3571)
  82. Plectus schneideri De Man, 1880
    See; Anaplectus granulosus (ref. ID; 3571)
  83. Plectus spicacaudatus Ebsary, 1985 (ref. ID; 7244 original paper)
  84. Plectus submersus Hirschmann, 1952
    See; Anaplectus submersus (ref. ID; 3571)
  85. Plectus subtilis Truskova, 1976 (ref. ID; 7244)
  86. Plectus telekii Mulk & Coomans, 1978 (ref. ID; 7244)
  87. Plectus tentaculatus Fuchs, 1930
    See; Tylocephalus tentaculatus (ref. ID; 3571)
  88. Plectus tenuis Bastian, 1865 (ref. ID; 3571) reported author and year? (ref. ID; 1774)
  89. Plectus thornei Ruhm, 1956 (ref. ID; 3571, 7244)
  90. Plectus triplogaster Orley, 1880 (ref. ID; 3571)
  91. Plectus tritici Bastian, 1865 (ref. ID; 3571)
  92. Plectus tubifer Cobb, 1914
    See; Anaplectus granulosus (ref. ID; 3571)
  93. Plectus turricaudatus Truskova, 1976 (ref. ID; 7244)
  94. Plectus varians Maggenti, 1961 (ref. ID; 3571, 7244)
  95. Plectus velox Bastian, 1865
    See; Plectus parietinus (ref. ID; 3571)
  96. Plectus vindobonensis Gunhold, 1953 (ref. ID; 3571, 7244)

Plectus amorphotelus Ebsary, 1985 (ref. ID; 7244 original paper)

Differential diagnosis

Plectus amorphotelus n. sp. is distinct amongst Plectus species because of the irregular, non-cuticularized, degenerate spinneret and the absence of caudal glands. The only other species of Plectus without a cuticularized spinneret is Plectus spicacaudatus n. sp. but this species has a pointed terminus, a set-off head, and anterior amphids lying between the cephalic setae. (ref. ID; 7244)

Descriptions

  • Female: Body in an open C shape. Cuticle 1.5 µm thick with transverse side, annules about 1.5 µm wide at midbody. Laterial field with three incisures, 3.5(3-4) µm wide. Lip region 8-10 µm wide, 4-5 µm high, continuous with body. En face with six lips. Cephalic setae extending to level of head apex, 4-5 µm long. Stoma 16(14-18) µm long, funnel shaped. Amphids situated 8-9 µm posterior to head apex and six to eight annules posterior to base of head. Amphid 2-2.5 µm wide or about 25% of head width. Excretory pore 81(75-105) µm from head apex or at 59(57-64)% of esophagus. Cervical seta in midlateral field, slightly posterior to excretory pore. Cardia hemispherical, 8-10 µm long or about one-fourth body width. Vulva transverse, lips continuous with body contour. Vagina simple, extending halfway into body. Rectum 20(18-25) µm long. Tail conoid, ventrally curved. Spinneret glands and cuticularized spinneret absent. Tail terminus with an irregularly shaped, degenerate spinneret. Caudal setae consist of a subdorsal pair posterior to the anus, a ventrolateral pair slightly posterior to midtail, and a dorsal seta near the tail terminus. (ref. ID; 7244)
  • Male: Unknown. (ref. ID; 7244)

    Type locality and habitat

    Collected July 1977 by the author from balsam fir as Kouchibouguac National Park, New Brunswick. (ref. ID; 7244)

    Type deposition

    Holotype female on slide No.281 and deposited in the type collection of the Canadian National Collection of Nematodes (CNCN), Ottawa. Three paratype females deposited with the University of California at Davis Nematode Collection (UCDNC), the remainder as above. (ref. ID; 7244)

    Measurements

  • Holotype (female): L=725 µm, a=18, b=4, c=10; c'=4, V=51. (ref. ID; 7244)
  • Paratypes (20 females): L=689(621-749) µm, a=22(18-26), b=4(3.4-4.6), c=10(8.7-11), c'=4.4(3.7-5.1), V=50(49-52). (ref. ID; 7244)

    Plectus cancellatus Zullini, 1978 (ref. ID; 7244 redescribed paper)

    Descriptions

    Body in an open C shape. Cuticle 3.5-5 µm thick with distinct transverse and longitudinal striae forming cuticular blocks about 2 µm wide at midbody. Blocks are usually present over entire body or confined to the esophageal region. The Hazen Lake population had some specimens with blocks over entire body and others with blocks confined to the esophageal region. Lateral field 4-5 µm consisting of four longitudinal incisures; the inner two incisures are joined by faint areolation. Head set off by constriction, narrower than body. En face with six lips. Cheilostom hexaradiate, globular in lateral view. Stoma 20-22 µm long, funnel-shaped. Amphids circular, 3-4 µm wide and 11-14 µm from head apex. Amphid width/head width 30%. Cephalic setae conical, 3.5-4 µm long. Excretory pore 133(127-139) µm from head apex lying at 57-62% of esophagus. Cervical seta in mid-lateral field slightly posterior to excretory pore. Cardia hemispherical, 12-14 µm long, 20-40% of body width. Vulva transverse, lips simple. Vagina extending about one-half distance into body. Rectum 27-36 µm long. Tail conoid, ventrally curved. Caudal glands present. Tail terminus with a 3 µm long cuticularized spinneret. A fringe of short rounded spines surrounds the tail terminus at the spinneret base. Caudal setae consist of a subdorsal pair posterior to anus, a subdorsal pair at two-thirds of tail, and a single subdorsal seta near the terminus. (ref. ID; 7244)

    Remarks

    The Canadian specimens of P. cancellatus differ from the original type description in that the cuticle is usually completely covered by cuticular blocks, the stoma is globular anteriorly and funnel shaped posteriorly, and the tail terminus at the spinneret base is covered with a fringe of short spines. (ref. ID; 7244)

    Measurements

  • Females (Hazen Lake, Northwest Territories N=5): L=958(871-1051) µm, a=21(20-22), b=4(3.8-4.3), c=8.8(8-9.9), c'=4.6(3.8-5), V=51(48-54). (ref. ID; 7244)
  • Females (Black Lake, Quebec N=7): L=842(792-886) µm, a=22(19-26), b=3.6(3.5-3.8), c=9.1(8.3-10.2), c'=4.1(3.8-4.3), V=53(51-55). (ref. ID; 7244)

    Plectus spicacaudatus Ebsary, 1985 (ref. ID; 7244 original paper)

    Differential diagnosis

    Plectus spicacaudatus n. sp. is distinct amongst Plectus because of the anterior amphid, set-off head, and pointed tail. (ref. ID; 7244)

    Descriptions

  • Female: Body in an open C shape. Cuticle 2 µm thick with transverse striae, annules 2 µm wide at midbody. Lateral field with three incisures 9 µm wide. Lip region 14-15 µm wide, 7 µm high, set off from body by a distict constriction. En face with six lips. Stoma 23(22-29) µm long, funnel shaped. Amphids 2-3 µm wide or about 15-20% of head width, 7-9 µm from head apex, and lying between the cephalic setae bases or one annule posterior. Cephalic setae 4 µm long, stout, not reaching level of head apex. Excretory pore 181(162-210) µm from head apex situated at 58(56-62)% of esophagus. Cervical seta located midway in lateral field posterior to excretory pore. Cardia hemispherical, 14-18 µm long, 20-30% of body width. Vulva transverse, lips continuous with body. Vagina simple, extending about halfway into body. Rectum 50-60 µm long. Tail conoid, ventrally curved. Caudal glands and cuticularized spinneret absent. Tail terminus pointed, lacking a spinneret. Caudal setae consist of a subdorsal pair posterior to anus, a ventro-lateral pair at two-thirds tail, and subdorsal pair near terminus. (ref. ID; 7244)
  • Male: Unknown. (ref. ID; 7244)

    Type locality and habitat

    Collected July 1965 from wild strawberry at Black Lake, Gatineau Park, Quebec. (ref. ID; 7244)

    Type deposition

    Holotype female mounted on slide No.404 and deposited in the Canadian National Collection of Nematodes (CNCN), Ottawa; two paratype females also deposited with the University of California at Davis Nematode Collection (UCDNC), Davis, California; remainder as above. (ref. ID; 7244)

    Measurements

  • Holotype (female): L=1346 µm, a=19, b=11.4, c=12, c'=3.3, V=50. (ref. ID; 7244)
  • Paratypes (8 females): L=1275(1180-1346) µm, a=21(18-26), b=4.2(3.8-4.7), c=11.0(10.4-12.6), c'=3.3(3.0-3.9), V=51(49-53). (ref. ID; 7244)

    Plectus tenuis Bastian, 1865 (ref. ID; 3571) reported author and year? (ref. ID; 1774)

    Descriptions

    This species indicates low pH waters. (ref. ID; 1774)