Carnivorous plant

Plants are considered carnivorous if they have these five traits: • capture prey in traps • kill the captured prey • digest the captured prey • absorb nutrients from the killed and digested prey • use those nutrients to grow and develop. Other traits may include the attraction and retention of prey. ==Trapping mechanisms==

'' are an example of pitfall traps. Five basic trapping mechanisms are found in carnivorous plants. • Pitfall traps (pitcher plants) trap prey in a rolled leaf that contains a pool of digestive enzymes or bacteria. • Flypaper traps use a sticky mucilage. • Snap traps utilise rapid leaf movements. • Bladder traps suck in prey with a bladder that generates an internal vacuum. • Lobster-pot traps, also known as eel traps, use inward-pointing hairs to force prey to move towards a digestive organ. These traps may be active or passive, depending on whether movement aids the capture of prey. For example, Triphyophyllum is a passive flypaper that secretes mucilage, but whose leaves do not grow or move in response to prey capture. Meanwhile, sundews are active flypaper traps whose leaves undergo rapid acid growth, which is an expansion of individual cells as opposed to cell division. The rapid acid growth allows the sundews' tentacles to bend, aiding in the retention and digestion of prey. Pitfall traps Characterised by an internal chamber, pitfall traps are thought to have evolved independently at least six times. Water can become trapped within the pitcher, making a habitat for other flora and fauna. This type of 'water body' is called a phytotelma. The simplest pitcher plants are probably those of Heliamphora, the marsh pitcher plant. In this genus, the traps are clearly derived from a simple rolled leaf whose margins have sealed together. These plants live in areas of high rainfall in South America such as Mount Roraima and consequently have a problem ensuring their pitchers do not overflow. To counteract this problem, natural selection has favoured the evolution of an overflow similar to that of a bathroom sink—a small gap in the zipped-up leaf margins allows excess water to flow out of the pitcher. '': note the small entrance to the trap underneath the swollen "balloon" and the colourless patches that confuse prey trapped inside. In the genus Sarracenia, the problem of pitcher overflow is solved by an operculum, which is essentially a flared leaflet that covers the opening of the rolled-leaf tube and protects it from rain. Possibly because of this improved waterproofing, Sarracenia species secrete enzymes such as proteases and phosphatases into the digestive fluid at the bottom of the pitcher. In at least one species, Sarracenia flava, the nectar bribe is laced with coniine, a toxic alkaloid also found in hemlock, which probably increases the efficiency of the traps by intoxicating prey. Most Heliamphora rely on bacterial digestion alone with the exception of a single species, Heliamphora tatei, which does produce digestive enzymes. The enzymes digest the proteins and nucleic acids in the prey, releasing amino acids and phosphate ions, which the plant absorbs. Darlingtonia californica, the cobra plant, possesses an adaptation also found in Sarracenia psittacina and, to a lesser extent, in Sarracenia minor: the operculum is balloon-like and almost seals the opening to the tube. This balloon-like chamber is pitted with areolae, chlorophyll-free patches through which light can penetrate. Insects, mostly ants, enter the chamber via the opening underneath the balloon. Once inside, they tire themselves trying to escape from these false exits, until they eventually fall into the tube. Prey access is increased by the "fish tails", outgrowths of the operculum that give the plant its name. Some seedling Sarracenia species also have long, overhanging opercular outgrowths; Darlingtonia may therefore represent an example of neoteny. '': a carnivorous bromeliad The second major group of pitcher plants are the monkey cups or tropical pitcher plants of the genus Nepenthes. In the hundred or so species of this genus, the pitcher is borne at the end of a tendril, which grows as an extension to the midrib of the leaf. Most species catch insects, although the larger ones, such as Nepenthes rajah, also occasionally take small mammals and reptiles. Nepenthes bicalcarata possesses two sharp thorns that project from the base of the operculum over the entrance to the pitcher. These likely serve to lure insects into a precarious position over the pitcher mouth, where they may lose their footing and fall into the fluid within. The pitfall trap has evolved independently in at least two other groups. The Albany pitcher plant, Cephalotus follicularis, is a small pitcher plant from Western Australia, with moccasin-like pitchers. The rim of its pitcher's opening (the peristome) is particularly pronounced (both secrete nectar) and provides a thorny overhang to the opening, preventing trapped insects from climbing out. The final carnivore with a pitfall-like trap is the bromeliad Brocchinia reducta. The tightly packed, waxy leaf bases of the strap-like leaves of this species form an urn. In most bromeliads, water collects readily in this urn and may provide habitats for frogs, insects. '' with prey. Flypaper traps '' bending in response to the trapping of an insect The flypaper trap utilises sticky mucilage or glue. The leaf of flypaper traps is studded with mucilage-secreting glands, which may be short (like those of the butterworts), or long and mobile (like those of many sundews). Flypapers have evolved independently at least five times. There is evidence that some clades of flypaper traps have evolved from morphologically more complex traps such as pitchers. In the genus Pinguicula, the mucilage glands are quite short (sessile), and the leaf, while shiny (giving the genus its common name of 'butterwort'), does not appear carnivorous. However, this belies the fact that the leaf is an extremely effective trap of small flying insects (such as fungus gnats), and its surface responds to prey by relatively rapid growth. This thigmotropic growth may involve rolling of the leaf blade (to prevent rain from splashing the prey off the leaf surface) or dishing of the surface under the prey to form a shallow digestive pit. The sundew genus (Drosera) consists of over 100 species of active flypapers whose mucilage glands are borne at the end of long tentacles, which frequently grow fast enough in response to prey (thigmotropism) to aid the trapping process. The tentacles of D. burmanii can bend 180° in a minute or so. Sundews are extremely cosmopolitan and are found on all the continents except the Antarctic mainland. They are most diverse in Australia, the home to the large subgroup of pygmy sundews such as D. pygmaea and to a number of tuberous sundews such as D. peltata, which form tubers that aestivate during the dry summer months. These species are so dependent on insect sources of nitrogen that they generally lack the enzyme nitrate reductase, which most plants require to assimilate soil-borne nitrate into organic forms. Similar to Drosera is the Portuguese dewy pine, Drosophyllum, which differs from the sundews in being passive. Its leaves are incapable of rapid movement or growth. Unrelated, but similar in habit, are the Australian rainbow plants (Byblis). Drosophyllum is unusual in that it grows under near-desert conditions; almost all other carnivores are either bog plants or grow in moist tropical areas. Recent molecular data (particularly the production of plumbagin) indicate that the remaining flypaper, Triphyophyllum peltatum, a member of the Dioncophyllaceae, is closely related to Drosophyllum and forms part of a larger clade of carnivorous and non-carnivorous plants with the Droseraceae, Nepenthaceae, Ancistrocladaceae and Plumbaginaceae. This plant is usually encountered as a liana, but in its juvenile phase, the plant is carnivorous. This may be related to a requirement for specific nutrients for flowering. Snap traps '' close rapidly when the sensitive hairs on the leaf lobes are triggered. carnivory process, Knowable Magazine Their trapping mechanism has also been described as a "mouse trap", "bear trap" or "man trap", based on their shape and rapid movement. However, the term snap trap is preferred as other designations are misleading, particularly with respect to the intended prey. Aldrovanda is aquatic and specialized in catching small invertebrates; Dionaea is terrestrial and catches a variety of arthropods, including spiders. The traps are very similar, with leaves whose terminal section is divided into two lobes, hinged along the midrib. Trigger hairs (three on each lobe in Dionaea muscipula, many more in the case of Aldrovanda) inside the trap lobes are sensitive to touch. When a trigger hair is bent, stretch-gated ion channels in the membranes of cells at the base of the trigger hair open, generating an action potential that propagates to cells in the midrib. These cells respond by pumping out ions, which may either cause water to follow by osmosis (collapsing the cells in the midrib) or cause rapid acid growth. The mechanism is still debated, but in any case, changes in the shape of cells in the midrib allow the lobes, held under tension, to snap shut, and interring the prey. This whole process takes less than a second. In the Venus flytrap, closure in response to raindrops and blown-in debris is prevented by the leaves having a simple memory: for the lobes to shut, two stimuli are required, 0.5 to 30 seconds apart. According to a recent study, calcium molecules move dynamically within the cells of the plant's leaves when a carnivorous plant touches live prey. Changing calcium levels make leaves move to catch prey, likely by producing more hormones related to defense. The snapping of the leaves is a case of thigmonasty (undirected movement in response to touch). Further stimulation of the lobe's internal surfaces by the struggling insects causes the lobes to close even tighter (thigmotropism), sealing the lobes hermetically and forming a stomach in which digestion occurs over a period of one to two weeks. Once this process is triggered, it cannot be reversed and requires more stimulation to trigger the next steps. Leaves can be reused three or four times before they become unresponsive to stimulation, depending on the growing conditions. Bladder traps '', showing stolon, branching leaf-shoots, and transparent bladder traps Bladder traps are exclusive to the genus Utricularia, or bladderworts. The bladders (vesiculae) pump ions out of their interiors. Water follows by osmosis, generating a partial vacuum inside the bladder. The bladder has a small opening, sealed by a hinged door. In aquatic species, the door has a pair of long trigger hairs. Aquatic invertebrates such as Daphnia touch these hairs and deform the door by lever action, releasing the vacuum. The invertebrate is sucked into the bladder, where it is digested. Many species of Utricularia (such as U. sandersonii) are terrestrial, growing in waterlogged soil, and their trapping mechanism is triggered in a slightly different manner. Bladderworts lack roots, but terrestrial species have anchoring stems that resemble roots. Temperate aquatic bladderworts generally die back to a resting turion during the winter months, and U. macrorhiza appears to regulate the number of bladders it bears in response to the prevailing nutrient content of its habitat. Similarly, Nepenthes jamban is a combination of pitfall and flypaper traps because it has a sticky pitcher fluid. Most Sumatran nepenthes, like N. inermis, also have this method. For example, N. dubia and N. flava also use this method. Borderline carnivores To be defined as carnivorous, a plant must first exhibit an adaptation of some trait specifically for the attraction, capture, or digestion of prey. Only one trait needs to have evolved that fits this adaptive requirement, as many current carnivorous plant genera lack some of the above-mentioned attributes. The second requirement is the ability to absorb nutrients from dead prey and gain a fitness advantage from the integration of these derived nutrients (mostly amino acids and ammonium ions) Despite this, there are cases where plants appear carnivorous, in that they fulfill some of the above definition, but are not truly carnivorous. Some botanists argue that there is a spectrum of carnivory found in plants: from completely non-carnivorous plants like cabbages, to borderline carnivores, to unspecialised and simple traps, like Heliamphora, to extremely specialised and complex traps, like that of the Venus flytrap. By some definitions this would still constitute botanical carnivory. Likewise, the seeds of Shepherd's Purse, bracts of Passiflora foetida, and flower stalks and sepals of triggerplants (Stylidium) appear to trap and kill insects, but their classification as carnivores is contentious. Two genera of liverwort, Colura and Pleurozia, have sac-shaped leaves that trap and kill ciliates and may digest them. A species of pitcher plant, Nepenthes ampullaria, has evolved away from being a carnivore. Rather than catching animals, it catches falling leaves in its pitchers. ==Digestion==

Specialized multicellular secretion glands produce digestive fluid that smother, kill, and digest prey as well as make a solution to assimilate released nutrients. Saccharides are often found in plants that have adhesive traps or plants that use viscous secretion to retain captured prey. The digestion fluid is often nutrient poor and has ions K, Na, Ca and Mg (for species in the Nepenthes genera for example), along with numerous proteins which vary across genera. Peroxidases are also involved for some species. The body of the prey is decomposed by a cocktail of hydrolytic enzymes which are stored in sub-cellular compartments or synthesized over and over as needed. Proteins of digestive fluid include proteases, chitinases (partly destroy exoskeleton of insects), phosphatases, and nucleases. ==Evolution==

General pattern of independent development in multiple lineages Charles Darwin spent 16 years growing carnivorous plants, experimenting with them in the greenhouse of his home in Kent, Down House. In his pioneering book Insectivorous Plants (1875) Darwin concluded that carnivory in plants was convergent, writing that carnivorous genera Utricularia and Nepenthes were not "at all related to the [carnivorous family] Droseraceae". The evolution of carnivorous plants is obscured by the paucity of their fossil record. Very few fossils have been found, and then usually only as seed or pollen. Carnivorous plants are generally herbs, and their traps are produced by primary growth. They generally do not form readily fossilisable structures such as thick bark or wood. Inferences from trap mechanism Despite meager fossil evidence, much can be deduced from the structure of current traps and their ecological interactions. It is widely believed that carnivory evolved under extremely nutrient-poor conditions, leading to a cost-benefit model for botanical carnivory. Cost-benefit models are used under the assumption that there is a set amount of potential energy available to an organism, which leads to trade-offs wherein energy is allocated to certain functions to maximize competitive ability and fitness. For carnivory, the trait could only evolve if the increase in nutrients from capturing prey exceeded the cost of investment in carnivorous adaptations. and evolved from active flypaper traps into snap traps. Hairy (or more specifically, stalked-glandular) leaves can catch and retain drops of rainwater, especially if shield-shaped or peltate, thus promoting bacteria growth. Insects land on the leaf, become mired by the surface tension of the water, and suffocate. Bacteria jumpstart decay, releasing from the corpse nutrients that the plant can absorb through its leaves. This foliar feeding can be observed in most non-carnivorous plants. Plants that were better at retaining insects or water therefore had a selective advantage. Rainwater can be retained by cupping the leaf, and pitfall traps may have evolved simply by selection pressure for the production of more deeply cupped leaves, followed by "zipping up" of the margins and subsequent loss of most of the hairs. Alternatively, insects can be retained by making the leaf stickier by the production of mucilage, leading to flypaper traps. The only traps that are unlikely to have descended from a hairy leaf or sepal are the carnivorous bromeliads (Brocchinia and Catopsis): These plants use the urn – a characteristic part of all bromeliads, not just the carnivorous ones – for a new purpose, and build on it by the production of wax and the other paraphernalia of carnivory. Leaves shaped like pitchers and lobster-pots The lobster-pot traps of Genlisea are difficult to interpret. They may have developed from bifurcated pitchers that later specialised on ground-dwelling prey; or, perhaps, the prey-guiding protrusions of bladder traps became more substantial than the net-like funnel found in most aquatic bladderworts. Whatever their origin, the helical shape of the lobster pot is an adaptation that displays as much trapping surface as possible in all directions when buried in moss. '' are unlikely to have descended from a hairy leaf or sepal. The traps of the bladderworts may have derived from pitchers that specialised in aquatic prey when flooded, like Sarracenia psittacina does today. Escaping prey in terrestrial pitchers have to climb or fly out of a trap, and both of these can be prevented by wax, gravity and narrow tubes. However, a flooded trap can be swum out of, so in Utricularia, a one-way lid may have developed to form the door of a proto-bladder. Later, this may have become active by the evolution of a partial vacuum inside the bladder, tripped by prey brushing against trigger hairs on the door of the bladder. The active glue traps use rapid plant movements to trap their prey. Rapid plant movement can result from actual growth, or from rapid changes in cell turgor, which allow cells to expand or contract by quickly altering their water content. Slow-moving flypapers like Pinguicula exploit growth, while the Venus flytrap uses such rapid turgor changes which make glue unnecessary. The stalked glands that once made glue became teeth and trigger hairs in species with active snap traps – an example of natural selection hijacking preexisting structures for new functions. of the relationships within the Caryophyllales indicate that the Droseraceae, Triphyophyllum, Nepenthaceae and Drosophyllum, while closely related, are embedded within a larger clade that includes non-carnivorous groups such as the tamarisks, Ancistrocladaceae, Polygonaceae and Plumbaginaceae. The tamarisks possess specialised salt-excreting glands on their leaves, as do several of the Plumbaginaceae (such as the sea lavender, Limonium), which may have been co-opted for the excretion of other chemicals, such as proteases and mucilage. Some of the Plumbaginaceae (e.g. Ceratostigma) also have stalked, vascularised glands that secrete mucilage on their calyces and aid in seed dispersal and possibly in protecting the flowers from crawling parasitic insects. The balsams (such as Impatiens), which are closely related to the Sarraceniaceae and Roridula, similarly possess stalked glands. Philcoxia is unique in the Plantaginaceae as a result of its subterranean stems and leaves, which have been shown to be used in the capture of nematodes. These plants grow in sand in Brazil, where they are likely to receive other nutrients. Like many other types of carnivorous plant, stalked glands are seen on the leaves. Enzymes on the leaves are used to digest the worms and release their nutrients. Carnivory in angiosperms Botanical carnivory has evolved in several independent families peppered throughout the angiosperm phylogeny, showing that carnivorous traits underwent convergent evolution multiple times to create similar morphologies across disparate families. Results of genetic testing published in 2017 found an example of convergent evolution – a digestive enzyme with the same functional mutations across unrelated lineages. ==Ecology and modeling of carnivory==

Carnivorous plants are widespread but rather rare. They are almost entirely restricted to habitats such as bogs, where soil nutrients are extremely limiting, but where sunlight and water are readily available. Only under such extreme conditions is carnivory favored to an extent that makes the adaptations advantageous. The archetypal carnivore, the Venus flytrap, grows in soils with almost immeasurable nitrate and calcium levels. Plants need nitrogen for protein synthesis, calcium for cell wall stiffening, phosphate for nucleic acid synthesis, and iron and magnesium for chlorophyll synthesis. The soil is often waterlogged, which favours the production of toxic ions such as ammonium, and its pH is an acidic 4 to 5. Ammonium can be used as a source of nitrogen by plants, but its high toxicity means that concentrations high enough to fertilise are also high enough to cause damage. '' is one of the few carnivorous plants to grow in dry soil However, the habitat is warm, sunny, constantly moist, and the plant experiences relatively little competition from low growing Sphagnum moss. Still, carnivores are also found in very atypical habitats. Drosophyllum lusitanicum is found around desert edges and Pinguicula valisneriifolia on limestone (calcium-rich) cliffs. In all the studied cases, carnivory allows plants to grow and reproduce using animals as a source of nitrogen, phosphorus and possibly potassium. However, there is a spectrum of dependency on animal prey. Pygmy sundews are unable to use nitrate from soil because they lack the necessary enzymes (nitrate reductase in particular). Common butterworts (Pinguicula vulgaris) can use inorganic sources of nitrogen better than organic sources, but a mixture of both is preferred. In carnivorous plants, the leaf is not just used to photosynthesise, but also as a trap. Changing the leaf shape to make it a better trap generally makes it less efficient at photosynthesis. For example, pitchers have to be held upright, so that only their opercula directly intercept light. The plant also has to expend extra energy on non-photosynthetic structures like glands, hairs, glue and digestive enzymes. To produce such structures, the plant requires ATP and respires more of its biomass. Hence, a carnivorous plant will have both decreased photosynthesis and increased respiration, making the potential for growth small and the cost of carnivory high. Being carnivorous allows the plant to grow better when the soil contains little nitrate or phosphate. In particular, an increased supply of nitrogen and phosphorus makes photosynthesis more efficient, because photosynthesis depends on the plant being able to synthesise very large amounts of the nitrogen-rich enzyme RuBisCO (ribulose-1,5-bis-phosphate carboxylase/oxygenase), the most abundant protein on Earth. It is intuitively clear that the Venus flytrap is more carnivorous than Triphyophyllum peltatum. The former is a full-time moving snap-trap; the latter is a part-time, non-moving flypaper. The energy "wasted" by the plant in building and fuelling its trap is a suitable measure of the carnivory of the trap. Using this measure of investment in carnivory, a model can be proposed. In general, carnivorous plants are poor competitors, because they invest too heavily in structures that have no selective advantage in nutrient-rich habitats. They succeed only where other plants fail. Carnivores are to nutrients what cacti are to water. Carnivory only pays off when the nutrient stress is high and where light is abundant. When these conditions are not met, some plants give up carnivory temporarily. Sarracenia spp. produce flat, non-carnivorous leaves (phyllodes) in winter. Light levels are lower than in summer, so light is more limiting than nutrients, and carnivory does not pay. The lack of insects in winter exacerbates the problem. Damage to growing pitcher leaves prevents them from forming proper pitchers, and again, the plant produces a phyllode instead. '' may be due to an unusually high need for potassium at a certain point in the life cycle, just before flowering. '' in a road cut in Palau. Showing habit and habitat. Many other carnivores shut down in some seasons. Tuberous sundews die back to tubers in the dry season, bladderworts to turions in winter, and non-carnivorous leaves are made by most butterworts and Cephalotus in the less favourable seasons. Utricularia macrorhiza varies the number of bladders it produces based on the expected density of prey. Part-time carnivory in Triphyophyllum peltatum may be due to an unusually high need for potassium at a certain point in the life cycle, just before flowering. The more carnivorous a plant is, the less conventional its habitat is likely to be. Venus flytraps live in a very specialised habitat, whereas less carnivorous plants (Byblis, Pinguicula) are found in less unusual habitats (i.e., those typical for non-carnivores). Byblis and Drosophyllum both come from relatively arid regions and are both passive flypapers, arguably the lowest maintenance form of trap. Venus flytraps filter their prey using the teeth around the trap's edge, so as not to waste energy on hard-to-digest prey. In evolution, laziness pays, because energy can be used for reproduction, and short-term benefits in reproduction will outweigh long-term benefits in anything else. Carnivory rarely pays, so even carnivorous plants avoid it when there is too little light or an easier source of nutrients, and they use as few carnivorous features as are required at a given time or for a given prey item. There are very few habitats stressful enough to make investing biomass and energy in trigger hairs and enzymes worthwhile. Many plants occasionally benefit from animal protein rotting on their leaves, but carnivory that is obvious enough for the casual observer to notice is rare. Nepenthes rajah has a remarkable mutualism with two unrelated small mammals, the mountain treeshrew (Tupaia montana) and the summit rat (Rattus baluensis). The tree shrews and the rats defecate into the plant's traps while visiting them to feed on sweet, fruity secretions from glands on the pitcher lids. The tree shrew also has a similar relationship with at least two other giant species of Nepenthes. More subtly, Hardwicke's woolly bat (Kerivoula hardwickii), a small species, roosts beneath the operculum (lid) of Nepenthes hemsleyana. The bat's excretions that land in the pitcher pay for the shelter, as it were. To the plant the excreta are more readily assimilable than intact insects would be. There also is a considerable list of Nepenthes endophytes; these are microbes other than pathogens that live in the tissues of pitcher plants, often apparently harmlessly. Another important area of symbiosis between carnivorous plants and insects is pollination. While many species of carnivorous plant can reproduce asexually via self-pollination or vegetative propagation, many carnivorous plants are insect-pollinated. Outcross pollination is beneficial as it increases genetic diversity. This means that carnivorous plants undergo an evolutionary and ecological conflict often called the pollinator-prey conflict. There are several ways by which carnivorous plants reduce the strain of the pollinator-prey conflict. For long-lived plants, the short-term loss of reproduction may be offset by the future growth made possible by resources obtained from prey. Other plants might "target" different species of insect for pollination and prey using different olfactory and visual cues. ==Conservation threats==

Approximately half of the plant species assessed by the IUCN are considered threatened (vulnerable, endangered or critically endangered). Common threats are habitat loss as a result of agriculture, collection of wild plants, pollution, invasive species, residential and commercial development, energy production, mining, transportation services, geologic events, climate change, severe weather, and many other anthropogenic activities. Species in the same genus were proven to face similar threats. Threat by continent is deemed highly variable, with threats found for 19 species in North America, 15 species in Asia, seven species in Europe, six species in South America, two species in Africa, and one species in Australia Indicator species' such as Sarracenia reveal positive associations with regard to these threats. Certain threats are also positively correlated themselves, with residential and commercial development, natural systems modifications, invasive species, and pollution having positive associations. Conservation research is aiming to further quantify the effects of threats, such as pollution, on carnivorous plants, as well as to quantify the extinction risks. Only 17% of species had been assessed as of 2011, according to the IUCN. Carnivorous plant conservation will help maintain important ecosystems and prevent secondary extinctions of specialist species that rely on them ==Classification==

The classification of all flowering plants is currently in a state of flux. In the Cronquist system, the Droseraceae and Nepenthaceae were placed in the order Nepenthales, based on the radial symmetry of their flowers and their possession of insect traps. The Sarraceniaceae was placed either in the Nepenthales, or in its own order, the Sarraceniales. The Byblidaceae, Cephalotaceae, and Roridulaceae were placed in the Saxifragales; and the Lentibulariaceae in the Scrophulariales (now subsumed into the Lamiales). In more modern classification, such as that of the Angiosperm Phylogeny Group, the families have been retained, but they have been redistributed amongst several disparate orders. It is also recommended that Drosophyllum be considered in a monotypic family outside the rest of the Droseraceae, probably more closely allied to the Dioncophyllaceae. The current recommendations are shown below (only carnivorous genera are listed): Dicots '' '' '' '' • Asterales (sunflower and daisy order) • Stylidiaceae • Stylidium (trigger plants, a borderline carnivore) • Caryophyllales, (carnation order) • Dioncophyllaceae • Triphyophyllum (a tropical liana) • Drosophyllaceae • Drosophyllum (Portuguese dewy pine) • Droseraceae (sundew family) • Aldrovanda (waterwheel plant) • Dionaea (Venus flytrap) • Drosera (sundews) • †Droserapollis • †Droserapites • †Droseridites • †Fischeripollis • †Saxonipollis • Nepenthaceae (tropical pitcher-plant family) • Nepenthes (tropical pitcher plants or monkey-cups, including Anurosperma) • Ericales (heather order) • Roridulaceae • Roridula (a borderline carnivore) • Sarraceniaceae (trumpet pitcher family) • Sarracenia (North American trumpet pitchers) • Darlingtonia (cobra plant/lily) • Heliamphora (sun or marsh pitchers) • Lamiales (mint order) • Byblidaceae • Byblis (rainbow plants) • Lentibulariaceae (bladderwort family) • Pinguicula (butterworts) • Genlisea (corkscrew plant) • Utricularia (bladderworts, including Polypompholyx, the fairy aprons or pink petticoats and Biovularia an obsolete genus) • Martyniaceae (all borderline carnivores, related to the sesame plant) • Ibicella • Plantaginaceae (plantain family) • Philcoxia (recently discovered carnivorous genus feeding on nematodes). • Oxalidales (wood sorrel order) • Cephalotus (Albany pitcher plant) Monocots • Alismatales (water plantain order) • Tofieldiaceae • Triantha occidentalis • Poales (grass order) • Bromeliaceae (bromeliad or pineapple family) • Brocchinia (a terrestrial bromeliad) • Catopsis (a borderline carnivore) • Eriocaulaceae (pipewort family) • Paepalanthus bromelioides (a borderline carnivore) == Gallery of prey ==

File:Sarracenia. Dicyrtomina.2.jpg|Collembola (Dicyrtomina minuta) trapped inside a leaf of Sarracenia purpurea File:Sarracenia. Idia.jpg|Glossy Black Idia (Idia lubricalis) moth trapped by Sarracenia purpurea File:Sarracenia. Lebia grandis.2.jpg|Carabid beetle (Lebia grandis) trapped by Sarracenia purpurea File:Dionaea, muscoid fly.jpg|Muscoid fly trapped by Dionaea muscipula File:Dionaea Paria beetle.jpg|Leaf beetle (Paria) trapped by Dionaea muscipula File:Drosera. Limonia.jpg|Limoniid cranefly (Limonia) trapped by Drosera filiformis File:Drosera. Phalaenophana.jpg|Dark-banded Owlet moth (Phalaenophana pyramusalis) trapped by Drosera filiformis File:Drosera. Eusarca confusaria.jpg|Confused eusarca moth (Eusarca confusaria) trapped by Drosera filiformis File:Drosera. Tabanus dorsal 2.jpg|Horse fly (Tabanus) trapped by Drosera filiformis File:Drosophila melanogaster ♀ Melgen, 1830, Drosera capensis Linnaeus, 1753 1100.1.2171.JPG|Red-eyed vinegar fly (Drosophila melanogaster) fly trapped by Drosera capensis File:Pinguicula moranensis (and prey).jpg| Darkwinged fungus gnat (Sciaridae) caught by Pinguicula moranensis ==Cultivation==

'' hybrids are easy to grow. In horticulture, carnivorous plants are considered a curiosity or a rarity, but are becoming more common in cultivation with the advent of mass-production tissue-culture propagation techniques. Venus flytraps are still the most commonly grown, usually available at garden centers and hardware stores, sometimes offered alongside other easy-to-grow varieties. Nurseries that specialise in growing carnivorous plants exclusively also exist, more uncommon or demanding varieties of carnivorous plants can be obtained from specialist nurseries. California Carnivores is a notable example of such a nursery in the US that specialises in the cultivation of carnivorous plants. It is owned and operated by horticulturalist Peter D'Amato. Rob Cantley's Borneo Exotics in Sri Lanka is a large nursery that sells worldwide. Although different species of carnivorous plants have different cultivation requirements in terms of sunlight, humidity, soil moisture, etc., there are commonalities. Most carnivorous plants require rainwater, or water that has been distilled or deionised by reverse osmosis. Common tap or drinking water contains minerals (particularly calcium salts) that will quickly build up and kill the plant. This is because most carnivorous plants have evolved in nutrient-poor, acidic soils and are consequently extreme calcifuges. They are therefore very sensitive to excessive soil-borne nutrients. Since most of these plants are found in bogs, almost all are very intolerant of drying. There are exceptions: tuberous sundews require a dry (summer) dormancy period, and Drosophyllum requires much drier conditions than most. Outdoor-grown carnivorous plants generally catch more than enough insects to keep themselves properly fed. Insects may be fed to the plants by hand to supplement their diet; however, carnivorous plants are generally unable to digest large non-insect food items; bits of hamburger, for example, will simply rot, and this may cause the trap, or even the whole plant, to die. A carnivorous plant that catches no insects at all will rarely die, although its growth may be impaired. In general, these plants are best left to their own devices: after underwatering with tap-water, the most common cause of Venus flytrap death is prodding the traps to watch them close and feeding them inappropriate items. Most carnivorous plants require bright light, and most will look better under such conditions, as this encourages them to synthesise red and purple anthocyanin pigments, (or betalain pigments within Caryophyllales). Nepenthes and Pinguicula will do better out of full sun, but most other species are happy in direct sunlight. Carnivores mostly live in bogs, and those that do not are generally tropical. Hence, most require high humidity. On a small scale, this can be achieved by placing the plant in a wide saucer containing pebbles that are kept permanently wet. Small Nepenthes species grow well in large terraria. Many carnivores are native to cold temperate regions and can be grown outside in a bog garden year-round. Most Sarracenia can tolerate temperatures well below freezing, despite most species being native to the southeastern United States. Species of Drosera and Pinguicula also tolerate subfreezing temperatures. Nepenthes species, which are tropical, require temperatures from 20 to 30 °C (70 to 90°F) to thrive. '' and a few other species. Carnivorous plants require appropriate nutrient-poor soil. Most appreciate a 3:1 mixture of Sphagnum peat to sharp horticultural sand (coir is an acceptable, and more ecofriendly substitute for peat). Nepenthes will grow in orchid compost or in pure Sphagnum moss. Carnivorous plants are themselves susceptible to infestation by parasites such as aphids or mealybugs. Although small infestations can be removed by hand, larger infestations necessitate use of an insecticide. Isopropyl alcohol (rubbing alcohol) is effective as a topical insecticide, particularly on scale insects. Diazinon is an excellent systemic insecticide that is tolerated by most carnivorous plants. Malathion and Acephate (Orthene) have also been reported as tolerable by carnivorous plants. Although insects can be a problem, by far the biggest killer of carnivorous plants (besides human maltreatment) is grey mold (Botrytis cinerea). This thrives under warm, humid conditions and can be a real problem in winter. To some extent, temperate carnivorous plants can be protected from this pathogen by ensuring that they are kept cool and well ventilated in winter and that any dead leaves are removed promptly. If this fails, a fungicide is in order. The easiest carnivorous plants for beginners are those from the cool temperate zone. These plants will do well under cool greenhouse conditions (minimum 5 °C; 40°F in winter, maximum 25 °C; 75°F in summer) if kept in wide trays of acidified or rain water during summer and kept moist during winter: • Drosera capensis, the Cape sundew: attractive strap-leaved sundew, pink flowers, very tolerant of maltreatment. • Drosera binata, the fork-leaved sundew: large, Y-shaped leaves. • Sarracenia flava, the yellow trumpet pitcher: yellow, attractively veined leaves, yellow flowers in spring. • Pinguicula grandiflora, the common butterwort: purple flowers in spring, hibernates as a bud (hibernaculum) in winter. Fully hardy. • Pinguicula moranensis, the Mexican butterwort: pink flowers, non-carnivorous leaves in winter. Venus flytraps will do well under these conditions but are actually rather difficult to grow: even if treated well, they will often succumb to grey mold in winter unless well ventilated. Some of the lowland Nepenthes are very easy to grow as long as they are provided with relatively constant, hot and humid conditions. ==Medicinal uses==

A study published in 2009 by researchers from Tel Aviv University indicates that secretions produced by carnivorous plants contain compounds that have anti-fungal properties and may lead to the development of a new class of anti-fungal drugs that will be effective against infections that are resistant to current anti-fungal drugs. ==Cultural depictions==

In 1789, Erasmus Darwin described Drosera in the second part of his poem The Botanic Garden: Possibly the earliest published account of a man-eating plant was a literary fabrication that first appeared in 1874. The story of Crinoida dajeeana, also known as the Devil Tree of Madagascar or Man-Eating Tree of Madagascar, first appeared in the daily edition of the New York World on 26 April 1874, and again in the weekly edition two days later. It purported to be from a German explorer named "Karl Leche" (also spelled as Karl or Carl Liche in later accounts), who described seeing a woman fed to a tree as a sacrifice by the "little known but cruel" "Mkodo tribe" of Madagascar. Authorship of the fantastical story would later be attributed by Frederick Maxwell Somers to one Edmund Spencer in the August 1888 issue of the magazine Current Literature. The story was reprinted widely, appearing as far away as the South Australian Register in 1881, where it was accompanied by an illustration of a tree consuming a woman. The account has been debunked as pure myth, and Dr. Liche, the Mkodos, and the tree itself were all fabrications. H. G. Wells imagined a tentacular blood-sucking plant in "The Flowering of the Strange Orchid" (1894). Since then, carnivorous plants have been the subject of popular interest and exposition, much of it highly inaccurate. Typically, these fictional depictions include exaggerated characteristics, such as enormous size or possession of abilities beyond the realm of reality, and can be viewed as a kind of artistic license. In a 1939 pamphlet on carnivorous plants written for the Field Museum, Sophia Prior recounts the Man-Eating Tree of Madagascar and other "stories of vegetable monsters". She dismisses them all as fables, and notes that they are invariably set in locales that are "indefinite" and "difficult of access". The Little Shop of Horrors|182x182px Fictional carnivorous plants have been featured in books, movies, television series, and video games. Some, such as the mockumentary The Hellstrom Chronicle (1971), use accurate depictions of carnivorous plants for cinematic purposes, while others depend more heavily on imagination. Two of the most famous examples of fictional carnivorous plants in popular culture are the triffids of John Wyndham's 1951 novel The Day of the Triffids and Audrey Jr./II, the man-eating plant in the 1960s black comedy The Little Shop of Horrors and its subsequent stage musical adaptation. Carnivorous flowers appear in one of the episodes of Zdenek Miler's famous Czech cartoon, The Little Mole (Krtek a medicína / The Little Mole and Medicine, 1987). Here, the little mole is in Africa, and the carnivorous flowers swallow a fly. The little mole also gets his hand caught, but he is unable to pull it out. The little mole tries to "feed" the carnivorous flower an incomprehensible stone in revenge, but the flower is "intelligent" and spits the stone back out. == References ==