Cystidicola stigmatura (Leidy, 1886) Ward & Magath 1917

Cystidicola stigmatura (Leidy, 1886) Ward & Magath, 1917

Synonym: Cystidicola cristivomeri White, 1941

Description (after White & Cable 1942, Ko & Anderson 1969, and Miscampbell et al. 2004). With characteristics of the genus.

Males: body 23 (17–31) long. Width at nerve ring 0.126 (0.101–0.144), at anus 0.125 (0.103–0.155). Buccal cavity 0.148 (0.124–0.174) long (Fig. 60 A). Nerve ring 0.399 (0.371–0.443) from anterior end [position of excretory pore not given]. Muscular oesophagus 0.527 (0.433–0.597) and glandular oesophagus 3.110 (2.370– 3.970) long. Cuticular bosses present on ventro-lateral surface of caudal alae. Spicules unequal: left one 0.900 (0.760–1.150), right one 0.200 (0.170–0.250) long. Seven to nine double pairs of pre-cloacal papillae present, the last pair sometimes single. Four pairs of post-cloacal papillae present, the 1st and 3rd single pairs, the 2nd and 4th double pairs. Phasmids 0.033 (0.025–0.037) from posterior end. Tail 0.244 (0.200–0.278) long (Fig. 60 B).

Females: body 28 (19–37) long. Width at nerve ring 0.142 (0.124–0.155), at anus 0.131 (0.113–0.151). Buccal cavity 0.149 (0.134–0.165) long. Nerve ring 0.405 (0.371–0.433) and excretory pore 0.608 (0.525–0.690) from anterior end. Muscular oesophagus 0.524 (0.474–0.567) and glandular oesophagus 3.070 (2.630–3.310) long.

Uterus amphidelphic, didelphic. Vulva slightly posterior to middle of body, 16 (10–21) from anterior end.

Phasmids 0.036 (0.034–0.037) from posterior end. Tail 0.212 (0.175–0.265) long. Fully developed eggs 0.045

(0.042–0.049) x 0.025 (0.023–0.026), bearing lateral “lobes” (“floats” or “mammillations” in litt.) (Fig. 60 C).

Site: swim bladder

Hosts: Coregonus artedi * (10, 14, 15, 19); Coregonus clupeaformis * (1, 6, 9, 10, 12, 14, 15, 16, 19, 24, 41); Coregonus hoyi *(10); Myoxocephalus thompsonii (29); Oncorhynchus gorbuscha (42); Oncorhynchus kisutch (17, 19); Oncorhynchus nerka (16); Osmerus mordax (16); Prosopium cylindraceum (10); Salvelinus alpinus (18, 20, 22, 23, 28, 30, 33, 34, 36, 37, 38, 39, 40); Salvelinus fontinalis (3, 5, 25); Salvelinus fontinalis x Salvelinus namaycush (16, 21); Salvelinus namaycush (2, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 25, 26, 27, 30, 31, 32, 33, 34, 35, 36, 37, 43)

Distribution: Alberta, British Columbia, Manitoba, Nunavut, NorthWest Territories, Ontario, Quebec, Saskatchewan, Yukon Territory

Records: 1. Smedley 1933 (AB, MB, SK); 2. White 1941 (ON); 3. Richardson 1942 (QC); 4. White and Cable 1942 (ON); 5. MacLulich 1943 (ON); 6. Miller 1945 (AB, NT); 7. Miller & Kennedy 1948 (NT); 8. Rawson 1951 (AB); 9. Stewart-Hay 1953a (MB); 10. Bangham 1955 (ON); 11. Rawson 1959 (SK); 12. Boyes & Anderson 1961 (ON); 13. Rawson 1961 (SK); 14. Ko & Anderson 1969 (ON); 15. Dechtiar 1972a (ON); 16. Collins & Dechtiar 1974 (ON); 17. Leong & Holmes 1974 (AB); 18. Jamieson & Freeman 1975 (NT); 19. Leong 1975 (AB); 20. Mudry & McCart 1978 (YT); 21. Dechtiar & Berst 1978 (ON); 22. Beverley-Burton 1978a (NT); 23. Eddy & Lankester 1978 (NT); 24. Pybus & Samuel 1978 (AB); 25. Lankester & Smith 1980 (ON); 26. Black & Lankester 1980 (EX, ON); 27. G. A. Black 1981b (EX, ON); 28. Black & Lankester 1981a (NT); 29. Black & Lankester 1981b (ON); 30. Black & Anderson 1982 (NU, ON); 31. Stewart & Bernier 1982 (NU); 32. G. A. Black 1983a (ON); 33. G. A. Black 1983b (NT, ON, QC, SK); 34. Stewart & Bernier 1983 (NT); 35. G. A. Black 1984a (ON); 36. G. A. Black 1984b (NT, NU, ON, SK); 37. Black & Lankester 1984 (NT, ON); 38. Curtis 1984 (NT, QC); 39. Stewart & Bernier 1984 (NT); 40. G. A. Black 1985 (NT); 41. Samuel 1985 (AB); 42. Anthony 1986 (ON); 43. Dechtiar & Lawrie 1988 (ON)

*Footnote: nematodes recovered from species of Coregonus were probably Cystidicola farionis misidentified

as C. stigmatura. Most of the early records of C. stigmatura from other non- Salvelinus hosts pre-date the work of

G. A. Black and coworkers and should be viewed with caution. Later records should be verified by examination of

deposited specimens.