Dioctophyme Collet-Meygret, 1802

Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, Zootaxa 4185 (1), pp. 1-274 : 18

* Dioctophyme Collet-Meygret, 1802

Generic diagnosis (after Mace & Anderson 1975, and Measures & Anderson 1985). Dioctophymatidae . Encapsulated L3 occur most commonly in hypaxial musculature of fishes, some in body cavity. Two circles of labial papillae surround mouth. Inner circle comprises six single papillae. Outer circle comprises four single and two double papillae. Amphids situated laterally between the interno- and externo-lateral papillae ( Fig. 15 A). Three large cells (one dorsal, two subventral) surround narrow buccal capsule and anterior end of oesophagus ( Fig. 15 B). Average length of oesophagus about 40% of total body length. A large circular muscle constitutes the oesophagointestinal sphincter ( Fig. 15 C). For length and width of male L3 from pumpkinseed Lepomis gibbosus see key above. Genital primordium diorchic and opisthorchic. For length and width of female L3 from pumpkinseed see key above. Vagina evident; non-patent vulva near oesophago-intestinal valve. Genital primordium monodelphic and opisthodelphic. Anus terminal in both sexes. Cuticles of 1st and 2nd moults retained.

One species, * D. renale , has been found as L 3 in Canadian fresh-water fishes. Adult D. renale occur in the kidneys of piscivorous mammals, especially mustelids and wild canids.

Figures

FIGURE 15. * Dioctophyme renale (Goeze, 1782) Stiles, 1901. A. en face view of larva; B. anterior end of larva; C. and D. (contiguous) anterior third of larva. (Redrawn from Mace & Anderson 1975)