The following species are described from fishes in deep-waters of the northwestern Atlantic Ocean: Fellodistomidae: Steringophorus furciger from Antimora rostrata, Coryphaenoides (Lionurus) carapinus, Lycenchelys paxillus, L. verrillii and Lycodes atlanticus; S. blackeri from Xenodermichthys copei, S. haedrichi n. sp. from Porogadus milesi, characterised by its lobate testes, sucker-ratio and long vitelline fields Megenteron crassum from Dicrolene intronigra; Zoogonidae: Brachyenteron rissoanum n. sp. from Polyacanthonotus rissoanus, characterised by the ovary position, the saccular seminal vesicle, the marginal genital pore and egg-size; Koiea notacanthi n. g., n. sp. from Notacanthus (?) chemnitzi, characterised by the Y-shaped excretory vesicle and the posteriorly placed testes.