These are three families, all having opposite leaves, which in some species may be photosynthetic. In the temperate Northern Hemisphere, the three commonly seen genera of Viscaceae, which have nonshowy flowers but white or red fruits, are Phoradendron, Viscum, and the dwarf mistletoes of Arceuthobium. Loranthaceae is a tropical family with showy yellow, orange, or red tubular flowers (another example), including Nuytsia floribunda, a tree of Australia that parasitizes roots of grasses. A remarkable endoparasitic loranth is Tristerix aphylla, which attacks a columnar cactus in Chile. Many species of mistletoes appear to have photosynthetic leaves, and thereby may be hemiparasites, but for most physiological studies of leaves have not been performed.
Root parasites belong to a number of families and are either nonphotosynthetic or photosynthetic. Broomrapes (either classified as family Orobanchaceae or subfamily Orobanchoideae of Scrophulariaceae) have nonphotosynthetic fleshy stems, e.g., the genera Orobanche, Conopholis, and Boschniakia. Other nonphotosynthetic root parasites are found in the families Lennoaceae, Hydnoraceae, Rafflesiaceae (e.g., Mitrostemon and Bdallophyton), and Balanophoraceae. Parasitic species in Santalaceae (the sandalwood family) and Krameriaceae (the ratony family) have photosynthetic leaves.
In temperate and some tropical regions of the world are parasitic vines of the Cuscutaceae (or the morning glory family, Convolvulaceae) called dodder, Cuscuta. Stems of dodder are orange to yellow or white. In tropical regions is the vine genus Cassytha of the laurel family (Lauraceae).
These are often cryptic until they flower and fruit. Stem and root parasites occur in the family Rafflesiaceae. In California is the rare Pilostyles thurberi, which bursts from stems of Psorothamnus, a leguminous woody desert plant. In Borneo is the plant with the largest flower, Rafflesia arnoldii, an endoparasite which erupts through the bark of trees and lianas in the grape family (Vitaceae). The nonphotosynthetic vines technically are also stem parasites.
Especially in the family Scrophulariaceae are some common hemiparasites, such as Indian paintbrush and owl's clover (Castilleja), lousewort (Pedicularis), and bird's beak (Cordylanthus). These have green, photosynthetic leaves, but a substantial portion of the parasite's carbon is derived from the host plant, parasitized from the roots.