Phylum Gnathostomulida Ax, 1956 - gnathostomulids
Order Filospermoidea Sterrer, 1972
Family Haplognathiidae Sterrer, 1972
Genus Haplognathia Sterrer, 1970
Haplognathia filum (Sterrer, 1966)
Haplognathia gubbarnorum (Sterrer, 1969)
Haplognathia lunulifera (Sterrer, 1969)
Haplognathia rosea (Sterrer, 1969)
Haplognathia ruberrima (Sterrer, 1966)
Haplognathia rubromaculata (Sterrer, 1969)
Haplognathia simplex (Sterrer, 1966)