Main Content
< Top page

The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Mononchoides

Mononchoides Rahm, 1928 (ref. ID; 7250) reported author and year? (ref. ID; 1663) = Monochoides (ref. ID; 1750)

Family Diplogasteridae (ref. ID; 7250)

ref. ID; 1663

Stoma moderately deep and wide; anterior edge of stoma bearing riblike structures; slender tubular section of stoma extending posterior to large tooth in stoma. Esophagus with two bulbs. Amphids obscure. (ref. ID; 1663)
  1. Mononchoides adjunctus Massey, 1966 (ref. ID; 7250)
  2. Mononchoides americanus (Steiner, 1930) (ref. ID; 7250)
  3. Mononchoides andersoni Ebsary, 1986 (ref. ID; 7250 original paper)
  4. Mononchoides angarensis Gagarin, 1983
    See; Koerneria angarensis (ref. ID; 7250)
  5. Mononchoides aquaticus Dassonville & Heyns, 1984
    See; Oigolaimella aquatica (ref. ID; 7250)
  6. Mononchoides bollingeri Goodrich, Hechler & Taylor, 1968 (ref. ID; 7250)
  7. Mononchoides changi Goodrich, Hechler & Tayor, 1968 (ref. ID; 7250)
  8. Mono(n?)choides colobocerus (ref. ID; 1751)
  9. Mononchoides elegans (Weingartner, 1955) (ref. ID; 7250)
  10. Mononchoides fortidens (Schuurmans Stekhoven, 1951) (ref. ID; 7250)
  11. Mononchoides gracilis Dassonville & Heyns, 1984 (ref. ID; 7250)
  12. Mononchoides histophorus (ref. ID; 7250)
  13. Mononchoides isolae (Meyl, 1953) (ref. ID; 7250)
  14. Mononchoides ivanegae Gagarin, 1983
    See; Koerneria ivanegae (ref. ID; 7250)
  15. Mononchoides leptospiculum (Weingartner, 1955) (ref. ID; 7250)
  16. Mononchoides longicauda Rahm, 1928 (ref. ID; 7250)
  17. Mononchoides piracicabensis (Rahm, 1928) (ref. ID; 7250)
  18. Mononchoides pulcher Zullini, 1981 (ref. ID; 7250)
  19. Mononchoides pylophilus (Weingartner, 1955) (ref. ID; 7250)
  20. Mononchoides ruriculus Gagarin, 1983
    See; Koerneria ruriculus (ref. ID; 7250)
  21. Mononchoides ruffoi Zullini, 1981 (ref. ID; 7250)
  22. Mononchoides splendidus (Koerner, 1954) (ref. ID; 7250), Monochoides splendidus (ref. ID; 1750)
  23. Mononchoides strenuus Gagarin, 1983 (ref. ID; 7250)
    See; Koerneria strenuus (ref. ID; 7250)
  24. Mononchoides striatulus (Fuchs, 1933) (ref. ID; 7250)
  25. Mononchoides striatus (Butschli, 1876) (ref. ID; 7250), Monochoides striatus (ref. ID; 1750)
  26. Mononchoides subamericanus (van der Linde, 1938( (ref. ID; 7250)
  27. Mononchoides trichuris (C0bb, 1893) (ref. ID; 7250)

Mononchoides andersoni Ebsary, 1986 (ref. ID; 7250 original paper)

Differential diagnosis

Mononchoides andersoni n. sp. is most closely related to M. gracilis Dassonville & Heyns, 1984, but differs by shorter body length (1086(1066-1246) µm vs. 1250(1080-1370) µm), lesser c value (2.6(2.4-2.7) vs. 3.1(2.9-3.3)), more anterior vulva (V=37(36-39)% vs. 40(38-42.5)%), and larger c' value (20(20-26) vs. 21(19-24)). Subventral telostomal teeth in M. andersoni separate this species from all other described Mononchoides species. (ref. ID; 7250)

Descriptions

Body slightly curved ventrally. Cuticle with 20-22 transversely striated longitudinal ridges. Body annules subtended by three fine bars. Head 14.5(13-15) µm wide, continuous with body. Lips six, each bearing a papilla. Amphid slitlike at level of dorsal tooth. Cheilostom ring comprising 6 weakly cuticularized plates each with an apparent bifurcate anterior fringe. Cheilorhabdions curvilinear in lateral view. Cheilostom barrel-shaped. Dorsal metarhabdion thornlike with a large clawlike mobile tooth. Right subventral metarhabdion curvilinear bearing a thornlike tooth with 4 or 5 denticles running tranversly along shaft. Left subventral metarhabdion bearing a rasplike plate. Telostom cylindrical 10-12 µm long, 5 µm wide, with 2 small 2-um subventral teeth at its base. Procorpus muscular surrounding base of telostom ventrally and extending to base of dorsal metarhabdion. Metacorpus slightly expanded 106(101-115) µm from head. Inner lining of bulb separated forming a valvelike structure. Isthmus and basal bulb 68(65-72) µm long, weakly muscled, and set off from the metacorpus. Ovaries paired, opposed, reflexed. Vulva opening a pore. Vagina and uterus lightly cuticularized. Rectum 23(22-25) µm long, tail 429(403-439) µm long, conical rapidly tapering through a filiform portion to the terminus. (ref. ID; 7250)
  • Male: Unknown. (ref. ID; 7250)

    Remarks

    Telostomal teeth in M. andersoni suggest placement in Koerneria. However, telostom morphology (elongate cylindrical versus funnel-shaped in Koerneria) and the typical cheilostom morphology and teeth indicate a closer affinity with Mononchoides in which the new species is placed. Members of the genus Koerneria differ from those of Mononchoides by having subventral telostomal teeth or swellings. These structures formerly were considered reliable; however, with the description of M. andersoni n. sp. the presence or absence of these structures for generic determination should be carefully reconsidered. Many species of Diplogasteridae were inadequately described by early workers, and the possibility exists that telostomal teeth and telostomal swellings may have been overlooked and may occur in many related species. Additional detailed research is strongly indicated to clarify the status of these structures. Until the structure of the telorhabdions is resolved, cheilostom and associated teeth rather than on the presence or absence of teeth in the telostom. Gagarin (1983) described four species of Mononchoides, M. angarensis, M. ivanegae, M. ruriculus, and M. strenuus from the USSR, but these species do not possess a cylindrical telostom as in other Mononchoides species. The funellike shape of the telostom, the structure of the cheilostom and teeth, together with the indication of telostomal swellings, strongly place these species more properly in Koerneria. Consequently, the following new combinations are proposed: Gagarin & Lemsina (1982) described Mononchoides tsalolichini n. sp. from the Soviet Union. However, in both the Russian and English summaries this species was referred to as Fictor tsalolichini n. sp. As the telostom of this species is not similar to Mononchoides but is typical of Fictor their description of M. tsalolichini is considered to be a lapsus calamni. This species is hereby corrected as Fictor tsalolichini. Dassonville & Heyns (1984) described the new species Mononchoides aquaticus from South Africa. This species however, does not appear to be a Mononchoides species because of the small asymmetrical telostom and the distinctive gubernaculum which is more typical of Oigolaimella Andrassy, 1968. This species is therefore transferred to Oigolaimella, becoming. Mononchoides fictor (Bastian, 1865) Goodey, 1963 is placed in species inquirenda due to the lack of sufficient morphological data pertaining to the cheilostom, telostom, and cheilostom armature. Without this vital information accurate placement is not possible and placement in species inquirienda is advisable. (ref. ID; 7250)

    Type locality and habitat

    Collected June 1975 by Dr. R.V. Anderson, for whom the species is named, from holly at the Agriculture Canada Research Station Arboretum at Vineland, Ontario. (ref. ID; 7250)

    Type deposition

    Holotype (female) and 3 paratype females mounted on type slide 409 and deposited in the Canadian National Collection of Nematodes, Ottawa. (ref. ID; 7250)

    Measurements

  • Holotype (female): L=1079 µm, a=36, b=6.5, c=2.4, c'=22, V=36. (ref. ID; 7250)
  • Paratypes (3 females): L=1086(1066-1246) µm, a=36, b=6.7(5.9-6.5), c=2.6(2.4-2.7), c'=22(20-26), V=37(36-39). (ref. ID; 7250)