Acanthochasmus Looss, 1901 accepted as Acanthostomum Looss, 1899 (original description)
Allocreadium Looss, 1900 (original description)
Anomotaenia Cohn, 1900 (original description)
Astiotrema Looss, 1900 (original description)
Chonopeltis Thiele, 1900 (original description)
Cryptocandona Kaufmann, 1900 (original description)
Cryptopolyzoon Dendy, 1900 (original description)
Cyphoniscus Verhoeff, 1900 accepted as Cyphoniscellus Verhoeff, 1901 (original description)
Cypridopsella Kaufmann, 1900 (original description)
Davaenaea Cohn, 1900 accepted as Davainea Blanchard & Railliet, 1891 (original description)
Deuterobaris Looss, 1900 (original description)
Dioecocestus Fuhrmann, 1900 (original description)
Dolichodemas Looss, 1900 (original description)
Emoleptalea Looss, 1900 (original description)
Enodiotrema Looss, 1900 (original description)
Eumegacetes Looss, 1900 (original description)
Eusminthurus Börner, 1900 accepted as Sminthurus Latreille, 1802 (original description)
Fimoscolex Michaelsen, 1900 (original description)
Gononemertes Bergendal, 1900 (original description)
Haploschendyla Verhoeff, 1900 (original description)
Leucocyphoniscus Verhoeff, 1900 (original description)
Marmostomum Looss, 1900 (original description)
Mesachorutes Absolon, 1900 (original description)
Microcypris Kaufmann, 1900 (original description)
Microscaphidium Looss, 1900 (original description)
Ooperipatus Dendy, 1900 (original description)
Orchidasma Looss, 1900 (original description)
Paracypridopsis Kaufmann, 1900 (original description)
Periphyllopsis Vanhöffen, 1900 (original description)
Pleurarmadillidium Verhoeff, 1900 (original description)
Ptychogonimus Lühe, 1900 (original description)
Sminthurides Börner, 1900 (original description)
Stenaphorura Absolon, 1900 (original description)
Stenophiloscia Verhoeff, 1908 (original description)
Stephanochasmus Looss, 1900 accepted as Stephanostomum Looss, 1899 (original description)
Stomylotrema Looss, 1900 (original description)
Synxenus Silvestri, 1900 accepted as Phryssonotus Scudder in Zittel, 1885 (original description)
Troglarmadillidium Verhoeff, 1900 (original description)
Typhlarmadillidium Verhoeff, 1900 (original description)
Typhlopodura Absolon, 1900 (original description)
Urotrema Braun, 1900 (original description)
Verhoeffiella Absolon, 1900 (original description)
Zygeupolia Thompson, 1900 (original description)