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 species of Cucullanellus 1 Cuticle 0.020-0.050 thick; mouth opening slightly inclined dorsally................................... C. cotylophora - Cuticle thinner than 0.020; mouth opening transverse to body axis............................................. 2 2 Ventral intestinal caecum not reaching nerve ring.................................................... C. kanabus - Ventral intestinal caecum reaches nerve ring, its apex sometimes double.................................. C. minutus