Invalid names: Cypricardia rugulosa Dana 1847 [synonym], Maeonia fragilis Dana 1849 [synonym], Myonia (Myonia) sulcatiformis Astafieva-Urbaitis 1976 [synonym], Myonia (Pachymyonia) bytantajensis Astafieva-Urbaitis 1976 [synonym], Myonia (Pachymyonia) lutkevitchi Astafieva-Urbaitis 1976 [synonym], Myonia minor Etheridge 1919 [synonym], Thracia alta Lutkevitch and Lobanova 1960 [synonym], Thracia longa Lutkevitch and Lobanova 1960 [synonym]