Tetrandria
Ing botani, tetrandria minangka kelas tanduran miturut sistem Linné. Padha saiki kembang hermaphrodite kanthi papat stamens sing gratis lan padha. Ordo lan genera sing kalebu ing golongan iki yaiku: Ordo 1. Monogynia Genus: Leucadendron, Protea, Cephalanthus, Globularia, Dipsacus, Scabiosa, Knautia, Hedyotis, Spermacoce, Sherardia, Asperula, Diodia, Knoxia, Houstonia, Galium, Crucianella, Rubia , Siphonanthus, Catesbaea, Ixora, Scurrula, Pavetta, Avicennia, Mitchella, Polypremum, Penaea, Blaeria, Buddleja, Exacum, Plantago, Scoparia, Centunculus, Sanguisorba, Cissus, Epimedium, Cornus, Tomex, Ptelea, Ludwigia, Oldenlandia, Ammannia , Isnardia, Trapa, Dorstenia, Elaeagnus, Brabejum, Rivina, Salvadora, Camphorosma, Alchemilla Order 2.