- Monostroma blytii Wittrock accepted as Monostroma blyttii (Areschoug) Wittrock, 1866 accepted as Monostroma obscurum (Kützing) J.Agardh, 1883 accepted as Ulvaria obscura (Kützing) P.Gayral ex C.Bliding, 1969
- Monostroma blyttii (Areschoug) Wittrock, 1866 accepted as Monostroma obscurum (Kützing) J.Agardh, 1883 accepted as Ulvaria obscura (Kützing) P.Gayral ex C.Bliding, 1969
- Monostroma grevillei (Thuret) Wittrock, 1866
- Monostroma obscurum (Kützing) J.Agardh, 1883 accepted as Ulvaria obscura (Kützing) P.Gayral ex C.Bliding, 1969
- Monostroma oxyspermum (Kützing) Doty, 1947 accepted as Gayralia oxysperma (Kützing) K.L.Vinogradova ex Scagel et al., 1989
- Monostroma pulchrum Farlow, 1881 accepted as Protomonostroma undulatum f. pulchrum (Farlow) M.J.Wynne, 1986