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 10.11646/zootaxa.4185.1.1 11620862-ddcf-4c01-b0d9-32867e03d74b 1175-5326 165530 0D054EDD-9CDC-4D16-A8B2-F1EBBDAD6E09 Family GUYANEMIDAE Petter, 1975 Family diagnosis (after Petter 1975 , and Adamson & Roth 1990 ). Head with four cephalic papillae, and four internal and four external labial papillae. Buccal capsule reduced or absent; peribuccal ring present. Oesophagus comprises short muscular portion and longer, cylindrical glandular portion. Female tail long. Functional anus present in mature worms. Functional vulva situated anteriorly. Monodelphic or didelphic. Male tail long, with pre- and post-cloacal papillae; caudal alae present or absent. Two equal spicules. Viviparous. Parasites of fishes. As presently defined Guyanemidae consists of two genera, namely, Guyanema Petter, 1975 , and Pseudodelphis Adamson & Roth, 1990 . Only Pseudodelphis has been recorded from Canadian fishes.