IRMNG Taxon list
Chiastozygus S. Gartner, 1968 †Chiastozygus acutus (Thierstein in Roth & Thierstein, 1972) Perch-Nielsen, 1984 †Chiastozygus amphipons (Bramlette & Martini, 1964) Gartner, 1968 †Chiastozygus angustus (L.E. Stover) S.W. Wise †Chiastozygus bifarius Bukry, 1969 †Chiastozygus cuneatus (Lyul'eva, 1967) Cepek & Hay, 1969 †Helicolithus trabeculatus (Gorka, 1957) Verbeek, 1977 †Chiastozygus fessus (Stover, 1966) Shafik, 1979 †Chiastozygus litterarius (Gorka, 1957) Manivit, 1971 †Chiastozygus mediaquadratus J.B. Risatti †Chiastozygus platyrhethus Hill, 1976 †Chiastozygus primitus Prins (1969) ex Rood et al., 1973 †Chiastozygus rotatorius J.B. Risatti †Chiastozygus striatus Black, 1971 †Chiastozygus tenuis Black, 1971 †Chiastozygus trabeculatus (H. Górka) J.B. Risatti †Chiastozygus ultimus Perch-Nielsen, 1981 †
