Phylum [Tracheophyta] Sinnott ex Caval.-Sm. (1998) - vascular plants Subphylum Polypodiophytina Reveal (1996) [monotypic] Class Polypodiopsida Cronquist, Takht. & Zimmerm. (1966) - ferns Subclass Ophioglossidae Klinge (1882) Order Ophioglossales Link (1833) [monotypic] Family Ophioglossaceae Martinov (1820) - ophioglossoids Subfamily Mankyuoideae J. R. Grant & B. Dauphin [monotypic] 1 Genus Mankyua B.Y.Sun, M.H.Kim & C.H.Kim (2002)