Guide to the Parasites of Fishes of Canada Part V: Nematoda Author Arai, Hisao P. Author Smith, John W. text Zootaxa 2016 4185 1 1 274 journal article 37874 10.11646/zootaxa.4185.1.1 11620862-ddcf-4c01-b0d9-32867e03d74b 1175-5326 165530 0D054EDD-9CDC-4D16-A8B2-F1EBBDAD6E09 Philometra cylindracea (Ward & Magath, 1917) Van Cleave & Mueller, 1934 Synonym: Ichthyonema cylindracea Ward & Magath, 1917 Description (after Molnar & Fernando 1975a ). With characteristics of the genus. Males: transparent, minute, 2.7 (2.5–2.8) long. Greatest width close to posterior end, 0.035 (0.031–0.041); at nerve ring level, 0.025 (0.021–0.031). Cuticle smooth and thin. Head rounded; papillae not observed. Mouth three- lobed. Oesophagus a muscular tube 0.615 (0.572–0.680) long, with a well-developed oesophageal gland alongside. Intestine narrow. Tail end blunt, with two lateral papillae connected by a narrow inconspicuous membrane. Spicules relatively short, subequal, right one 0.060 (0.049–0.071), left one 0.061 (0.049–0.075). Gubernaculum 0.038 (0.034–0.043) long, in the form of a bent chitinous plate with a spear-like posterior end ( Fig. 31 A). Females: Fully developed worms are coloured red and 97 (91–102) long. Body cylindrical, tapering slightly at both extremities; greatest width 0.9 (0.8–1.0). Cuticle thin and smooth. Body cavity filled by uterus full of larvae. Head rounded, with three lips and four inconspicuous papillae ( Fig. 31 B). Caudal end also rounded, showing two small lateral papillae ( Fig. 31 C). Oesophagus 2.3 (2.0–2.9) long, muscular and forming a bulb near mouth. Oesophageal gland very prominent with clearly visible nucleus at its centre ( Fig. 31 B). Intestine greater in width than posterior portion of oesophagus. Vulva atrophied. Two long, thin ovaries run in opposite directions connected by common uterine duct. Anterior ovary bent backwards near nerve ring region, the posterior one bent forwards at terminal end of intestine. Uterus packed with vigorously moving larvae; larvae are 0.36 (0.31–0.39) long and have rounded anterior ends and sharply attenuated tails ( Fig. 31 B,C). Site: body cavity Hosts: Aplodinotus grunniens (1); Perca flavescens (1, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12); Salvelinus fontinalis (2, 13); Sander vitreus (1) Distribution: Ontario , Quebec Records: 1. Bangham & Hunter 1939 (ON); 2. Fantham & Porter 1948 (QC); 3. Bangham 1955 (ON); Tedla 1969 (ON); 4. Tedla & Fernando 1969a (ON); 5. Tedla & Fernando 1972 (ON); 7. Dechtiar 1972a (ON); 8. Molnar et al. 1974 (ON); 9. Molnar & Fernando 1975a (ON); 10. Dechtiar & Christie 1988 (ON); 11. Dechtiar & Nepszy 1988 (ON); 12. Dechtiar et al. 1988 (ON); 13. Marcogliese & Cone 1991a (QC)