This group gathers Flowering Plants subcategory members belonging to the large and chemically distinctive order Caryophyllales, united less by obvious shared appearance than by an unusual pigment chemistry, most members color their flowers with betalains rather than the anthocyanins used elsewhere in flowering plants. It spans the cactus family Cactaceae, New World succulents adapted to extreme drought by storing water in a swollen, often spineless-leaved stem, the carnation family Caryophyllaceae, the amaranth and goosefoot family Amaranthaceae (spinach, beets, quinoa and the salt-tolerant saltbushes and glassworts), the buckwheat family Polygonaceae (rhubarb, knotweed and buckwheat itself), the four-o'clock family Nyctaginaceae, the tamarisk family Tamaricaceae, and two unrelated-looking carnivorous lineages, the sundews and Venus flytrap of the family Droseraceae and the pitcher plants of the Old World family Nepenthaceae, whose trapping habit evolved independently of this subcategory's other, Ericales-order pitcher plants.