Phylum Magnoliophyta Cronquist, Takht. & Zimmerm. ex Reveal (1996) see Infraphylum Angiospermae auct. Class Magnoliopsida Brongn. (1843) Subclass Magnoliidae Novák ex Takht. (1967) - angiosperms Superorder Magnolianae Takht. (1967) Order Aristolochiales Juss. ex Bercht. & J.Presl (1820) see Order Piperales Bercht. & J.Presl (1820) Family Aristolochiaceae Juss. (1789), nom. cons. - birthwort family Subfamily Aristolochioideae Burnett Tribe Aristolochieae Dumort. ex Spach (1841) Genus Isotrema Rafinesque (1819)