Taxonomy of mermithids (Nematoda: Mermithidae) of Canada and in particular of the Mackenzie and Porcupine river systems, and Somerset Island, N.W.T., with descriptions of eight new species and emphasis on the use of the male characters in identification

Abstract

Twenty-four described mermithids are listed as known members of the Canadian fauna. Five of these are redescribed, and eight new species are described; namely Capitomermis micropeos, Gastromermis plethelos, Gastromermis leptopeos, Gastromermis pachopeos, Hydromermis macrospiculatus, Neomesomermis leptoderos, Neomesomermis welchi, and Neomesomermis yukonensis. A taxonomic key is provided to separate the 10 genera to which the 24 species belong. Keys identify the species of the genera Gastromermis, Hydromermis, and Neomesomermis. Morphology of the male head and genitalia are critically analysed and consistent male characteristics incorporated into four keys.