Rafflesia, or stinking corpse lily, is a genus of parasitic flowering plants in the family Rafflesiaceae. The species have enormous flowers, the buds rising from the ground or directly from the lower stems of their host plants; one species has the largest flower in the world. Plants of the World Online lists up to 41 species from this genus, all of them are found throughout Southeast Asia.
Rafflesia
Replica of Rafflesia flower displayed in Philippine National Museum
Rafflesia on hanging roots. West Sumatra, Indonesia.
Rafflesia keithii bloom, approximately 80 cm in diameter near Taman Nasional Rafflesia Bengkulu, Indonesia
A parasitic plant is a plant that derives some or all of its nutritional requirements from another living plant. They make up about 1% of angiosperms and are found in almost every biome. All parasitic plants develop a specialized organ called the haustorium, which penetrates the host plant, connecting them to the host vasculature – either the xylem, phloem, or both. For example, plants like Striga or Rhinanthus connect only to the xylem, via xylem bridges (xylem-feeding). Alternately, plants like Cuscuta and some members of Orobanche connect to both the xylem and phloem of the host. This provides them with the ability to extract resources from the host. These resources can include water, nitrogen, carbon and/or sugars. Parasitic plants are classified depending on the location where the parasitic plant latches onto the host, the amount of nutrients it requires, and their photosynthetic capability. Some parasitic plants can locate their host plants by detecting volatile chemicals in the air or soil given off by host shoots or roots, respectively. About 4,500 species of parasitic plants in approximately 20 families of flowering plants are known.
Cuscuta, a stem holoparasite, on an Acacia tree in Pakistan
Mistletoe, an obligate stem hemiparasite
Striga witchweeds (white, center, attached to roots of the host) are economically important pests of the crop plants that they parasitize.
Newly emergent snow plant (Sarcodes sanguinea), a flowering plant parasitic on mycorrhizal fungi