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 Key to Superfamilies of ASCARIDOMORPHA 1 Lips absent, or markedly reduced and variable; mouth opening sometimes elongated dorso-ventrally; oesophagus short, simple and cylindrical, or short and divided into two portions having or not having same width; pharyngeal portion of oesophagus present or absent; pre-cloacal sucker may be present in male; less than 11 pairs of genital papillae in male...... Seuratoidea - With three well defined lips, usually large, sometimes separated by interlabia; oesophagus simple and cylindrical or terminated by swelling without valves; intestinal caeca present or absent; pre-cloacal sucker absent in male; genital papillae in male numerous................................................................................. Ascaridoidea