Venus flytrap
The Venus flytrap is a carnivorous plant native to the temperate and subtropical wetlands of North Carolina and South Carolina, on the East Coast of the United States. Although various modern hybrids have been created in cultivation, D. muscipula is the only species of the monotypic genus Dionaea. It is closely related to the waterwheel plant and the cosmopolitan sundews, all of which belong to the family Droseraceae. Dionaea catches its prey—chiefly insects and arachnids—with a "jaw"-like clamping structure, which is formed by the terminal portion of each of the plant's leaves; when an insect makes contact with the open leaves, vibrations from the prey's movements ultimately trigger the "jaws" to shut via tiny hairs on their inner surfaces. Additionally, when an insect or spider touches one of these hairs, the trap prepares to close, only fully enclosing the prey if a second hair is contacted within twenty seconds of the first contact. Triggers may occur as quickly as of a second from initial contact.
The requirement of repeated, seemingly redundant triggering in this mechanism serves as a safeguard against energy loss and to avoid trapping objects with no nutritional value; the plant will only begin digestion after five more stimuli are activated, ensuring that it has caught a live prey animal worthy of consumption. These hairs also possess a heat sensor. A forest fire, for example, causes them to snap shut, making the plant more resilient to periods of summer fires.
Although widely cultivated for sale, the population of the Venus flytrap has been rapidly declining in its native range., the species was under Endangered Species Act review by the U.S. Fish & Wildlife Service.
Etymology
The plant's common name refers to Venus, the Roman goddess of love. The genus name, Dionaea, refers to an epithet of the Greek goddess Aphrodite, while the species name, muscipula, is Latin for both "mousetrap" and "flytrap". The Latin word muscipula is derived from mus and decipula, while the homonym word muscipula is derived from musca and decipula.Historically, the plant was also known by the slang term "tipitiwitchet" or "tippity twitchet", possibly an oblique reference to the plant's resemblance to human female genitalia. The term is similar to the term tippet-de-witchet which derives from tippet and witchet. In contrast, the English botanist John Ellis, who gave the plant its scientific name in 1768, wrote that the plant name tippitywichit was an indigenous word from either Cherokee or Catawba. The plant name according to the Handbook of American Indians derives from the Renape word titipiwitshik which wind around, referring to the plant's leaves which wrap and trap its prey.
Discovery by Europeans
On 2 April 1759, the North Carolina colonial governor, Arthur Dobbs, penned the first written description of the plant in a letter to English botanist Peter Collinson. In the letter he wrote: "We have a kind of Catch Fly Sensitive which closes upon anything that touches it. It grows in Latitude 34 but not in 35. I will try to save the seed here." A year later, Dobbs went into greater detail about the plant in a letter to Collinson dated Brunswick, 24 January 1760.This was the first detailed recorded notice of the plant by Europeans. The description was before John Ellis's letter to The London Magazine on 1 September 1768, and his letter to Carl Linnaeus on 23 September 1768, in which he described the plant and proposed its English name Venus's Flytrap and scientific name Dionaea muscipula.
Description
The Venus flytrap is a small plant whose structure can be described as a rosette of four to seven leaves, which arise from a short subterranean stem that is actually a bulb-like object. Each stem reaches a maximum size of about three to ten centimeters, depending on the time of year; longer leaves with robust traps are usually formed after flowering. Flytraps that have more than seven leaves are colonies formed by rosettes that have divided beneath the ground.File:Drawing of Venus Flytrap.jpg|thumb|left|upright|Illustration from Curtis's Botanical Magazine by William Curtis
Fly trap leaves
The leaf blade is divided into two regions: a flat, heart-shaped photosynthesis-capable petiole, and a pair of terminal lobes hinged at the midrib, forming the trap which is the true leaf. The upper surface of these lobes contains red anthocyanin pigments and its edges secrete mucilage. The lobes exhibit rapid plant movements, snapping shut when stimulated by prey. The trapping mechanism is tripped when prey contacts one of the three hair-like trichomes that are found on the upper surface of each of the lobes. The mechanism is so highly specialized that it can distinguish between living prey and non-prey stimuli, such as falling raindrops; two trigger hairs must be touched in succession within 20 seconds of each other or one hair touched twice in rapid succession, whereupon the lobes of the trap will snap shut, typically in about one-tenth of a second. The edges of the lobes are fringed by stiff hair-like protrusions or cilia, which mesh together and prevent large prey from escaping. These protrusions, and the trigger hairs are likely homologous with the tentacles found in this plant's close relatives, the sundews. Scientists have concluded that the snap trap evolved from a fly-paper trap similar to that of Drosera.The holes in the meshwork allow small prey to escape, presumably because the benefit that would be obtained from them would be less than the cost of digesting them. If the prey is too small and escapes, the trap will usually reopen within 12 hours. If the prey moves around in the trap, it tightens and digestion begins more quickly.
Speed of closing can vary depending on the amount of humidity, light, size of prey, and general growing conditions. The speed with which traps close can be used as an indicator of a plant's general health. Venus flytraps are not as humidity-dependent as are some other carnivorous plants, such as Nepenthes, Cephalotus, most Heliamphora, and some Drosera.
The Venus flytrap exhibits variations in petiole shape and length and whether the leaf lies flat on the ground or extends up at an angle of about 40–60 degrees. The four major forms are: 'typica', the most common, with broad decumbent petioles; 'erecta', with leaves at a 45-degree angle; 'linearis', with narrow petioles and leaves at 45 degrees; and 'filiformis', with extremely narrow or linear petioles. Except for 'filiformis', all of these can be stages in leaf production of any plant depending on season, length of photoperiod, and intensity of light.
Other parts
The plant also has a flower on top of a long stem, about long. The flower is pollinated from various flying insects such as sweat bees, longhorn beetles and checkered beetles.Habitat and distribution
Habitat
The Venus flytrap is found in nitrogen- and phosphorus-poor environments, such as bogs, wet savannahs, and canebrakes. Small in stature and slow-growing, the Venus flytrap tolerates fire well and depends on periodic burning to suppress its competition. Fire suppression threatens its future in the wild. It survives in wet sandy and peaty soils. Although it has been successfully transplanted and grown in many locales around the world, it is native only to the coastal bogs of North and South Carolina in the United States, specifically within a radius of Wilmington, North Carolina. One such place is North Carolina's Green Swamp. There also appears to be a naturalized population of Venus flytraps in northern Florida as well as an introduced population in western Washington. The nutritional poverty of the soil is the reason it relies on such elaborate traps: insect prey provide the nitrogen for protein formation that the soil cannot. They tolerate mild winters, and require a period of winter dormancy to survive freezing temperatures and low photoperiods. Most professional carnivorous plant growers recommend dormancy, and Venus fly traps grown without dormancy may require more light, water, and food to remain healthy.They are full sun plants, usually found only in areas with less than 10% canopy cover. The habitats where it thrives are typically either too nutrient-poor for many noncarnivorous plants to survive, or frequently disturbed by fires which regularly clear vegetation and prevent a shady overstory from developing. It can be found living alongside herbaceous plants, grasses, sphagnum, and fire-dependent Arundinaria bamboos. Regular fire disturbance is an important part of its habitat, required every 3–5 years in most places for D. muscipula to thrive. After fire, D. muscipula seeds germinate well in ash and sandy soil, with seedlings growing well in the open post-fire conditions. The seeds germinate immediately without a dormant period.