[plants] Haeckel (1866) - plants vascular plants see Phylum Tracheophyta Sinnott ex Caval.-Sm. (1998) euphyllophytes see Clade Euphyllophyta Lecointre & Le Guyader 2006 [Cantino & Donoghue 2020] Spermatophyta Britton & Brown 1896 [Crane & Kenrick 1997], nom. cl. inval. - seed plants see Clade Spermatophyta Britton & Brown 1896 [Cantino, Doyle & Donoghue 2020] Class Magnoliopsida Brongn. (1843) Monocotyledons see Superorder Lilianae Takht. (1967) Order Alismatales R.Br. ex Bercht. & J.Presl (1820) Family Potamogetonaceae Bercht. & J.Presl (1823), nom. cons. - pondweed family 1 Genus Althenia Petit (1829) 2 Genus Groenlandia J. Gay (1854) 3 Genus Lepilaena J. Drummond ex Harv. (1855) 4 Genus Potamogeton L. (1753) 5 Genus Pseudalthenia 6 Genus Stuckenia 7 Genus Zannichellia L. (1753)