Capillaria, Zeder, 1800

Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, Zootaxa 4185 (1), pp. 1-274 : 23

Key to species of Capillaria

1 Male tail with large ventro-lateral lobes, and large paired caudal papillae; gravid worms with vulvar appendage; parasitic in marine fishes........................................................................................ 2

- Ventro-lateral lobes on male tail indistinct, and large paired caudal papillae; vulvar appendage absent; parasitic in fresh-water fishes.............................................................................................. 3

2 Spicule relatively short, ca 0.2 long. Pacific Ocean............................... Capillaria (Procapillaria) margolisi

- Spicule relatively long, ca 1.0– 1.4 in length. Atlantic Ocean......................... Capillaria (Procapillaria) gracilis

3 Evaginated spicular sheath spiny proximally only; mature eggs with non-protruding polar plugs................................................................................................ Capillaria (Capillaroides) catenata