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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Insulodrilus

Insulodrilus Brinkhurst, 1991 (ref. ID; 6563 original paper) reported author and year? (ref. ID; 1326)

Family Phreodrilidae: Subfamily Phreodriloidinae (ref. ID; 6563)

ref. ID; 1326

Generic characters are the pendant penis, the ventro-lateral spermathecal pores with short vestibulae at the pores, and the modified spermathecal chaetae. (ref. ID; 1326)

ref. ID; 6563

Phreodriloidinae with lateral chaetae in the dorsal bundles, with pendant penes, with ventral spermathecal pores possessing vestibulae varying from small to quite deep, but not involving the female funnels (paraphyletic). (ref. ID; 6563)

Remarks

This classification leaves much to be desired, and it is only proposed as a conservative measure to avoid introducing a great deal of new nomenclature. The position of the type species as well as campbellianus suggests a relationship with Astacopsidrilus (q.v.), but the apomorphic character states separating these taxa as well as litoralis from the rest in the cladogram involve the condition of the ventral chaetae, which requires careful reassessment. (ref. ID; 6563)

Type species

Phreodrilus lacustirs Benham, 1903 (ref. ID; 6563)
  1. Insulodrilus breviatria Brinkhurst, 1979 (ref. ID; 6563) or Brinkhurst & Fulton, 1979 (ref. ID; 7264)
  2. nsulodrilus campbellianus Benham, 1909 (ref. ID; 6563, 7264)
  3. Insulodrilus genitalisetifera Martin & Brinkhurst, 1994 (ref. ID; 1326 original paper)
  4. Insulodrilus lacustris (ref. ID; 6563)
  5. Insulodrilus litoralis Michaelsen, 1924 (ref. ID; 6563)
  6. Insulodrilus magnaseta Brinkhurst, 1979 (ref. ID; 6563)
  7. Insulodrilus martensi Martin & Giani, 1995 (ref. ID; 6620)
  8. Insulodrilus nudus Brinkhurst, 1979 (ref. ID; 6563)
  9. Insulodrilus plumaseta Brinkhurst, 1979 (ref. ID; 6563)
  10. Insulodrilus tanganyikae Brinkhurst, 1970 (ref. ID; 1326, 6563, 7264)
  11. Insulodrilus uniseta Brinkhurst, 1982 (ref. ID; 6563, 7264)

Insulodrilus genitalisetifera Martin & Brinkhurst, 1994 (ref. ID; 1326 original paper)

Descriptions

Length of holotype 4.26 mm, breadth at widest (segment XIV) 0.38 mm, more than 44 segments (specimen not inact). Two ventral chaetae per bundle, sigmoid with a slight nodulus. Upper tooth shorter than lower. Size and shape of the two ventral chaetae in each bundle similar along the entire body. On the first two segments, the chaetae are smaller, but with proportions being preserved. Ventral chaetae on XI and XIII replaced by modified genital chaetae of the form referred to as spermathecal chaetae. Two modified chaetae per bundle, thin, elongate, grooved ectal to the nodulus, slightly dissimilar in size and closely placed together (Remark; when the chaetae are separated due to the mounting), it clearly appears that the upper, grooved tip is responsible for the difference in size between both chaetae). No ventral chaetae on XII. Dorsal chaetae from III, (2)3(4) hair flanked by (3)4(5) "support" chaetae, the support chaetae being difficult to observe and not extending beyond the body wall. The support chaetae no longer visible from segment XXVII onwards. From about segment XXV, hair chaetae shorter and stouter, giving a spiny impression for the posterior segments. No dorsal chaetae On XIII. (ref. ID; 1326)
  • Male pores on XII. Vasa deferentia thin, opening into the base of atria near union with penis. Atria coiled, without lumen. Pendant penis, tubular in half of their lower part, wider in the upper half. Surface of penis with an alveolate relief. No cuticular penis sheath. Spermathecal pores ventrally on XIII. Spermathecae with ducts as long as the ampullae, with narrow lumina leading to short vestibulae. Voluminous ampullae filled with material showing a certain organization. Short circular clitellum on XIII. (ref. ID; 1326)

    Etymology

    Refers to the unusual presence of genital chaetae on the pregenital segment XI. (ref. ID; 1326)

    Type locality

    Delta of river Dama, near Rumonge (Burundi; 3 degrees 57'49"S, 29 degrees 24'33"E), Ponar grab, 50 m deep, sand and silty mud, 26 September 1991. (ref. ID; 1326)

    Measurements

    Length of holotype 4.26 mm, breadth at widest (segment XIV) 0.38 mm, more than 44 segments (specimen not intact). (ref. ID; 1326)

    Insulodrilus tanganyikae Brinkhurst, 1970 (ref. ID; 1326, 6563, 7264)

    Distribution

    Known only from Lake Tanganyika. (ref. ID; 1326)