Fictional botany: Duggara iridophylla

The vampire begonia (Duggara iridophylla) is not a true Begonia. It gets its name from the supposed resemblance of the leaves to rhizomatous begonias, as they are broad (up to 6 inches / 15 cm across), hairy, and frequently brightly colored in shades of green, yellow, orange, brown, black, and red. Surprisingly, leaf color does not appear to be determined by genetics, but is instead dependent on environmental factors at the point of germination, such as temperature, nutrient availability, or other factors. Coloration, once established, remains constant throughout the plant's life.

Duggara iridophylla is a perennial, native to boggy, nutrient-poor regions throughout the Northwestern United States and coastal British Columbia. Its leaves emerge from a short, thick stem and are held on long, slightly hairy petioles well away from the stem. The entire plant can be up to 2.5 feet (0.8 m) in diameter.

The common name derives from the method the plant uses to acquire nutrients: among the long, soft leaves and hairs are a few modified leaves which are nearly-transparent, extremely sharp blades about an eighth of an inch (3mm) wide and up to 1.5 inches (4 cm) long. These are specially adapted both to be able to slice the skin of animals brushing against the plant, or attempting to eat it, and also to be permeable to nutrients, in particular iron and manganese, which contact them. A single one of these modified leaves is capable of absorbing half its weight in iron (III) chloride (FeCl₃), according to laboratory tests. In the wild, minerals are not likely to be administered so directly, but spines are also capable of absorbing nitrogen, sodium, potassium, and other components of blood. Excessive amounts of iron are stored in the roots until needed or else translocated to developing seeds. Plants deprived of animal blood for long periods may produce small or pale new growth, grow more slowly, or be more susceptible to attack by insects and disease. It is eaten by several species of beetle in its native range.

The flowers are produced in late summer at the end of a tall (to 3 ft. / 0.9 m), thick stalk and may become a globe of flowers and buds 6 inches (15 cm) across. They are intensely fragrant, and have been described as smelling like pineapple. Flowers are usually vivid red, though pink and white varieties have been seen in the wild. They are pollinated by birds, though they are self-fertile if left unpollinated by the end of the season. The flowers eventually form small hook-covered seed capsules which hook onto animal fur and are transported to new locations.

Duggara is occasionally cultivated as a houseplant and garden plant because of its beautiful foliage, though its environment is difficult to reproduce outside of its native habitat, and its numerous, nearly-invisible and razor-sharp spines pose special difficulties for those who would try to cultivate it. Two cultivars are sold: the first, called 'Dracula,' has red flowers, leaves which are black with red veins, and a smaller habit than the species. 'Dracula' does reproduce true from seeds; whatever genetic mechanism controls the variable coloration appears to have been disabled. The second widely available cultivar is called 'Mary Fair,' and retains the variable colors of the species, but the leaf edges are ruffled, and the flowers are a delicate pink color and have a slightly sweeter scent. Duggara does not appear to have invasive tendencies.

Duggara is uniquely adapted for its chosen lifestyle; not only does it have a novel means of acquiring necessary transition metals, but it's variable color is thought to be a defense against animals which would otherwise learn which plants to avoid: a wild animal may learn to avoid a red and green plant but still approach (and be cut by) one which is black and orange. This color-changing ability, if it could be transferred to other plant genera, could provide many new asexually-propagated cultivars of unrelated garden plants nearly overnight. Consequently, Duggara iridophylla is of considerable interest to plant breeders. It is also suspected of having antibiotic and anticoagulant properties, as cuts inflicted by Duggara bleed profusely (if briefly) but rarely become infected.