Venus Flytrap Facts

The Venus flytrap (Dionaea muscipula) is a rare carnivorous plant that captures and digests its prey with fleshy, hinged jaws. These jaws are actually modified portions of the plant's leaves.

The plant gets its common name for Venus, the Roman goddess of love. This refers either to the plant trap's supposed resemblance to female genitalia or to the sweet nectar it uses to lure its victims. The scientific name comes from Dionaea ("daughter of Dione" or Aphrodite, the Greek goddess of love) and muscipula (Latin for "mousetrap").

Description

The Venus flytrap is a small, compact flowering plant. A mature rosette has between 4 and seven leaves and reaches a size up to 5 inches. Each leaf blade has a petiole capable of photosynthesis and a hinged trap. The trap contains cells that produce the red pigment anthocyanin. Within each trap are trigger hairs that sense touch. The edges of the trap lobes are lined with stiff protrusions which lock together when the trap closes to prevent prey from escaping.

Habitat

The Venus flytrap lives in damp sandy and peaty soil. It is native only to the coastal bogs of North and South Carolina. The soil is poor in nitrogen and phosphorus, so the plant needs to supplement photosynthesis with nutrients from insects. North and South Carolina get mild winters, so the plant is adapted to cold. Plants that do not undergo winter dormancy eventually weaken and die. Northern Florida and western Washington host successful naturalized populations.

Diet and Behavior

While the Venus flytrap relies on photosynthesis for most of its food production, it requires supplementation from proteins in prey to meet its nitrogen requirements. Despite its name, the plant primarily catches crawling insects (ants, beetles, spiders) rather than flies. In order for prey to be captured, it must touch the trigger hairs inside the trap more than once. Once triggered, it only takes about a tenth of a second for the trap lobes to snap shut. Initially the fringes of the trap loosely hold the prey. This allows very small prey to escape, as they aren't worth the energy expenditure of digestion. If the prey is large enough, the trap fully closes to become a stomach. Digestive hydrolase enzymes are released into the trap, nutrients are absorbed through the leaf's interior surface, and 5 to 12 days later the trap opens to release the remaining chitin shell of the insect.

Large insects can damage the traps. Otherwise, each trap can only function a few times before the leaf dies and must be replaced.

Reproduction

Venus flytraps are capable of self-pollination, which occurs when pollen from the plant's anthers fertilize a flower's pistil. However, cross-pollination is common. The Venus flytrap does not capture and eat insects that pollinate its flowers, such as sweat bees, checkered beetles, and long-horned beetles. Scientists aren't entirely certain how the pollinators avoid being trapped. It could be that the color of the flowers (white) attracts pollinators, while the color of the traps (red and green) attracts prey. Other possibilities include scent differences between the flower and trap, and flower placement above the traps.

After pollination, the Venus flytrap produces black seeds. The plant also reproduces by dividing into colonies from rosettes that form beneath mature plants.

Conservation Status

The IUCN lists the Venus flytrap's conservation status as "vulnerable." The population of plants in the species' natural habitat is decreasing. As of 2014, an estimated 33,000 plants remained, all within a 75 mile radius of Wilmington, NC. Threats include poaching, fire prevention (the plant is fire resistant and relies on periodic burning to control competition), and habitat loss. In 2014, North Carolina Senate Bill 734 made collecting wild Venus flytrap plants a felony.

Care and Cultivation

The Venus flytrap is a popular houseplant. While it's an easy plant to keep, it has certain requirements. It must be planted in acidic soil with good drainage. Usually, it is potted in a mixture of sphagnum peat moss and sand. It's important to water the plant with rainwater or distilled water to provide the proper pH. The plant needs 12 hours of direct sunlight per day. It should not be fertilized and should only be offered an insect if it appears unhealthy. In order to survive, a Venus flytrap requires exposure to a period of cooler temperatures to simulate winter.

While the Venus flytrap will grow from seed, it is usually cultivated by dividing the rosettes in the spring or summer. Commercial propagation for nurseries occurs in vitro from plant tissue culture. Many interesting mutations for size and color are available from nurseries.

Uses

In addition to cultivation as a houseplant, Venus flytrap extract is sold as a patent medicine named "Carnivora." The American Cancer Society states that Carnivora is sold as an alternative treatment for skin cancer, HIV, rheumatoid arthritis, herpes, and Crohn's disease. However, the health claims have not been supported by scientific evidence. The purified active ingredient in the plant extract, plumbagin, does show antitumor activity.

Sources

• D'Amato, Peter (1998). The Savage Garden: Cultivating Carnivorous Plants. Berkeley, California: Ten Speed Press. ISBN 978-0-89815-915-8.
• Hsu YL, Cho CY, Kuo PL, Huang YT, Lin CC (Aug 2006). "Plumbagin (5-Hydroxy-2-methyl-1,4-naphthoquinone) Induces Apoptosis and Cell Cycle Arrest in A549 Cells through p53 Accumulation via c-Jun NH2-Terminal Kinase-Mediated Phosphorylation at Serine 15 in Vitro and in Vivo". J Pharmacol Exp Ther. 318 (2): 484–94. doi:10.1124/jpet.105.098863
• Jang, Gi-Won; Kim, Kwang-Soo; Park, Ro-Dong (2003). "Micropropagation of Venus fly trap by shoot culture". Plant Cell, Tissue and Organ Culture. 72 (1): 95–98. doi:10.1023/A:1021203811457
• Leege, Lissa (2002) "How Does the Venus Flytrap Digest Flies?" Scientific American.
• Schnell, D.; Catling, P.; Folkerts, G.; Frost, C.; Gardner, R.; et al. (2000). "Dionaea muscipula". The IUCN Red List of Threatened Species. 2000: e.T39636A10253384. doi:10.2305/IUCN.UK.2000.RLTS.T39636A10253384.en