Genlisea | |
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Genlisea violacea leaves: green above-ground leaves and colorless underground trap leaves | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Lamiales |
Family: | Lentibulariaceae |
Genus: | Genlisea A.St.-Hil. (1833) |
Subgenera and sections | |
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Global distribution of Genlisea |
Genlisea ( /ˌdʒɛnlɪˈsiːə/ JEN-liss-EE-ə) is a genus of carnivorous plants also known as corkscrew plants. The 30 or so species grow in wet terrestrial to semi-aquatic environments distributed throughout Africa and Central and South America. The plants use highly modified underground leaves to attract, trap and digest minute microfauna, particularly protozoans. Although suggested a century earlier by Charles Darwin, carnivory in the genus was not proven until 1998. [1]
The generic name Genlisea honors the French writer and educator Stéphanie Félicité Ducrest de St-Albin, comtesse de Genlis. [2]
Several species in the genus, including G. margaretae , G. aurea , and G. tuberosa , possess the smallest known genomes of all flowering plants. [3] [4] [5]
As stated, Genlisea has a wide range of genetic diversity which can be shown in various phenotypic traits. For example, G. tuberosa develops tubers, one to three occurring per plant. This allows for carbohydrate and water storage as it is found in areas prone to fire. Other species present with a thickened stolon. [6]
Genlisea are small herbs, growing from a slender rhizome and bearing two morphologically distinct leaf types— photosynthetic foliage leaves aboveground and highly modified subterranean leaves used to trap prey. The plants lack roots, although the subterranean traps perform many of the functions normally performed by roots, such as anchorage and absorption of water and nutrients.
Several to many flowers are held by a slender, erect, and often tall inflorescence. As in other members of the bladderwort family, the corolla is fused into a bilobed tube tapering to a spur, with the lower lip of the corolla having three lobes. [2] The calyx is five-lobed, in contrast to Utricularia's three-lobed calyx. [7] Corolla colors are generally yellow or violet to mauve, although a few species are white or cream. [7] The lower lip forms a palate that functions as the guide to the spur that contains the nectar by providing olfactory and mechanical stimuli for nearby pollinators like bees and flies. At a microscopic level, the palate has glandular trichomes, [8] which are small hairs that store and secrete secondary metabolites in order to provide protection from herbivory. [9] The glandular trichomes contain no nectar secretion, suggesting that they are scent glands. [8] These above ground structures are not shown to be directly participating in carnivorous activities.
Depending on species, the photosynthetic leaves are linear to spatulate in shape and 0.5–5 cm (1⁄4–2 in) in length. [2]
The subterranean traps are white, lacking chlorophyll or any other pigmentation. They consist of a cylindrical stalk, widening at some distance below the surface into a hollow bulb-like utricle, and continuing as a hollow cylinder some further distance. At this point the stalk bifurcates into two furrowed spirals, between which the cylinder opening acts as the trap entrance. The furrows of the spiraled trap arms are lined with hairs pointing inward and toward the bifurcation. The hollow cylinder section leading from the bifurcation to the utricle is likewise lined with upward-pointing curved hairs. Some species produce two trap forms, one shorter and one longer, which probably target different prey groups. These corkscrew-like structures passively capture protozoa and other metazoan. Since these traps occur in soil, they are continuously stimulated due to the vast microfauna found in the soil. Due to continuous stimulation, the plant actively secretes digestive enzymes in order to aid with digestion to gain more nitrogen, phosphorus, and other minerals. [10] Phosphatase has been detected in all types of glands, allowing for the breakdown of prey and uptake of phosphorus in low-nutrient soils. Although not completely understood, the oxygen concentration inside Genlisea traps is negligible. For this reason, it is thought that anoxic conditions could be the mechanisms in which prey are killed. At the same time, anaerobic bacteria survive. [11]
Twenty-nine species are currently recognised in the genus. [12] Two varieties are also considered valid: G. aurea var. minor and the autonymous G. aurea var. aurea. [12] Intraspecific determination depends almost wholly upon the inflorescence, particularly upon the indumentum. [7] Genetic variation is an interesting area of attention as it has an incredible high rate of nucleotide substitution rates across nucleus, chloroplast, and mitochondria when compared to other angiosperms. Due to a mutation leading to changes in phenotypic traits found in the mitochondria, reactive oxygen species are produced which ultimately lead to DNA damage and further mutations. [13]
Species | Authority | Year | Image | Distribution | Subgenus | Section | Genome size (Mbp) [5] |
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Genlisea africana | Oliv. | 1865 | Africa | Genlisea | Africanae | 740 | |
Genlisea angolensis | R.D.Good | 1924 | Africa | Genlisea | Africanae | - | |
Genlisea aurea | A.St.-Hil. | 1833 | South America | Genlisea | Genlisea | 64 & 117 - 131 | |
Genlisea barthlottii | S.Porembski, Eb.Fisch. & Gemmel | 1996 | Africa | Genlisea | Africanae | - | |
Genlisea exhibitionista [14] | Rivadavia & A.Fleischm. | 2011 | South America | Tayloria | - | ||
Genlisea filiformis | A.St.-Hil. | 1833 | South America, Central America, Cuba | Genlisea | Genlisea | - | |
Genlisea flexuosa [14] | Rivadavia, A.Fleischm. & Gonella | 2011 | South America | Tayloria | - | - | |
Genlisea glabra | P.Taylor | 1967 | South America | Genlisea | Genlisea | - | |
Genlisea glandulosissima | R.E.Fr. | 1916 | Africa | Genlisea | Recurvatae | 154-189 | |
Genlisea guianensis | N.E.Br. | 1900 | South America | Genlisea | Genlisea | 289 | |
Genlisea hispidula | Stapf | 1904 | Africa | Genlisea | Africanae | 1510 - 1550 | |
Genlisea lobata | Fromm | 1989 | South America | Tayloria | - | 1200 - 1722 | |
Genlisea margaretae | Hutch. | 1946 | Africa, Madagascar | Genlisea | Recurvatae | 113 - 195 | |
Genlisea metallica [14] | Rivadavia & A.Fleischm. | 2011 | South America | Tayloria | - | 1057 | |
Genlisea nebulicola [14] | Rivadavia, Gonella & A.Fleischm. | 2011 | South America | Tayloria | - | - | |
Genlisea nigrocaulis | Steyerm. | 1948 | South America | Genlisea | Genlisea | 73 - 86 | |
Genlisea oligophylla [14] | Rivadavia & A.Fleischm. | 2011 | South America | Tayloria | - | - | |
Genlisea oxycentron | P.Taylor | 1954 | South America, Trinidad | Genlisea | Genlisea | 75 | |
Genlisea pallida | Fromm & P.Taylor | 1985 | Africa | Genlisea | Recurvatae | - | |
Genlisea pulchella | Tutin | 1934 | South America | Genlisea | Genlisea | - | |
Genlisea pygmaea | A.St.-Hil. | 1833 | South America | Genlisea | Genlisea | 161 - 179 | |
Genlisea repens | Benj. | 1847 | South America | Genlisea | Genlisea | 77 - 86 & 142 - 150 | |
Genlisea roraimensis | N.E.Br. | 1901 | South America | Genlisea | Genlisea | - | |
Genlisea sanariapoana | Steyerm. | 1953 | South America | Genlisea | Genlisea | - | |
Genlisea stapfii | A.Chev. | 1912 | Africa | Genlisea | Africanae | - | |
Genlisea subglabra | Stapf | 1906 | Africa | Genlisea | Africanae | 1471 - 1622 | |
Genlisea tuberosa [15] | Rivadavia, Gonella & A.Fleischm. | 2013 | South America | Genlisea | Genlisea | 61 [4] | |
Genlisea uncinata | P.Taylor & Fromm | 1983 | South America | Tayloria | - | 995 - 1062 | |
Genlisea violacea | A.St.-Hil. | 1833 | South America | Tayloria | - | 1005 - 1609 |
The genus was discovered by Augustin François César Prouvençal de Saint-Hilaire, [2] who in 1833 described four species: G. aurea , G. filiformis , G. pygmaea , and G. violacea .
The genus has a 25-fold range in genome size among its species and notably includes some of the smallest known plant genomes. [5] For example, the genome of G. nigrocaulis is 86 Mbp (1C; 2n = 40) while that of its close relative G. hispidula (1C; 2n = 40) is 1550 Mbp, 18-fold larger. More than one genome size has been measured in G. aurea and G. repens, suggesting that di- and tetraploid individuals exist. [5]
Genlisea traps host a microbe community of bacteria (dominant species consisting of anaerobic Clostridium sp. and pectolytic Dickeya sp. [16] ), green algae, microbial fungi, protists of SAR group, and minute metazoans. Through extensive research, the trap's bacterial community has been discovered as serving the ecological importance of being prey due to Genlisea plants relying on the digestive enzymatic systems from microbes in order to aid their own carnivorous digestion. [17]
Pitcher plants are several different carnivorous plants that have modified leaves known as pitfall traps—a prey-trapping mechanism featuring a deep cavity filled with digestive liquid. The traps of what are considered to be "true" pitcher plants are formed by specialized leaves. The plants attract and drown their prey with nectar.
Droseraceae is a family of carnivorous flowering plants, also known as the sundew family. It consists of approximately 180 species in three extant genera. Representatives of the Droseraceae are found on all continents except Antarctica.
Lentibulariaceae is a family of carnivorous plants containing three genera: Genlisea, the corkscrew plants; Pinguicula, the butterworts; and Utricularia, the bladderworts.
Utricularia, commonly and collectively called the bladderworts, is a genus of carnivorous plants consisting of approximately 233 species. They occur in fresh water and wet soil as terrestrial or aquatic species across every continent except Antarctica. Utricularia are cultivated for their flowers, which are often compared with those of snapdragons and orchids, especially amongst carnivorous plant enthusiasts.
Byblis is a small genus of carnivorous plants, sometimes termed the rainbow plants for the attractive appearance of their mucilage-covered leaves in bright sunshine. Native to Australia and New Guinea, it is the only genus in the family Byblidaceae. The first species in the genus was described by the English botanist Richard Anthony Salisbury in 1808. Eight species are now recognised.
Genlisea aurea is one of the largest carnivorous species in the genus Genlisea. It has pale bundles of root-like organs up to about 15 cm long under ground that attract, trap, and digest protozoans. These organs are subterranean leaves, which lack chlorophyll. G. aurea is endemic to Brazil, where it grows with several other species of Genlisea. It possesses an exceptionally small genome for a flowering plant.
A protocarnivorous plant, according to some definitions, traps and kills insects or other animals but lacks the ability to either directly digest or absorb nutrients from its prey like a carnivorous plant. The morphological adaptations such as sticky trichomes or pitfall traps of protocarnivorous plants parallel the trap structures of confirmed carnivorous plants.
Genlisea margaretae is a carnivorous species in the genus Genlisea native to areas of Madagascar, Tanzania, and Zambia. It has pale bundles of root-like organs up to about 20 cm long under ground that attract, trap, and digest protozoans. These organs are subterranean leaves, which lack chlorophyll. It had been known to possess the smallest known genome of any flowering plant as of 2006, but was later surpassed by the related species Genlisea tuberosa.
Utricularia gibba, commonly known as the humped bladderwort or floating bladderwort, is a small, mat-forming species of carnivorous aquatic bladderwort. It is found on all continents except Antarctica.
Utricularia resupinata, popularly known as lavender bladderwort or northeastern bladderwort, is a small perennial subaquatic carnivorous plant that belongs to the genus Utricularia. It is native to eastern Canada, the United States, and Central America. This plant species has an interesting etymology, growth pattern, ecology, and research history. As a plant that is threatened or endangered in many of the States where it is found, it is a candidate for sound conservation efforts.
Philcoxia is a genus of seven rare plant species in the Plantaginaceae that are endemic to Brazil and resemble terrestrial species of the genus Utricularia. The genus, formally described in 2000, consists of the species P. bahiensis, P. goiasensis, P. minensis, P. tuberosa, P. rhizomatosa, P. maranhensis and P. courensis, each of the first three named for the Brazilian state to which it is endemic. The species are characterized by subterranean stems, peltate leaves at or below the soil surface, and five-lobed calyces. Their habitat has been reported as areas of white sand in the midst of cerrado vegetation at an elevation between 800 and 1450 m. Initial descriptions of the genus included suspicions that the plethora of stalked capitate glands on the upper surfaces of leaves was an indication that these species may be carnivorous. A study published in 2007 tested P. minensis for protease activity, a typical test for the carnivorous syndrome, and could detect none. Later studies detected other digestive enzymes such as phosphatases and qualitatively assessed prey digestion and nutrient uptake, suggesting that it is a true carnivorous plant. The genus epithet honors David Philcox (1926-2003), a botanist at Kew Gardens who worked extensively in tropical Scrophulariaceae.
Utricularia foliosa, the leafy bladderwort, is a large suspended aquatic carnivorous plant that belongs to the genus Utricularia. It is probably a perennial plant that cultivates in lake, swamps and ponds. U. foliosa is native to Africa and North and South America, widely distributed among many countries. Although, they are widely distributed around the world, very little studies have been contributed to U. foliosa. They like to sprout all year long, and found in large body of water. The environment that Utricularia foliosa are found in are experiencing negative anthropogenic impacts such as drainage and conversion to urban or agricultural activities are causing rapid environmental degradation.
Utricularia purpurea, the eastern purple bladderwort, is a medium-sized suspended aquatic carnivorous plant that belongs to the genus Utricularia. U. purpurea is endemic to North and Central America. It has been suggested that U. purpurea may have partially lost its appetite for carnivory. Richards (2001) did an extensive study in the field on it and noted that trapping rates of the usual Utricularia prey were significantly lower than in other species in the genus. Richards concludes that this species can still trap and digest arthropod prey in its specialized bladder traps, but does so sparingly. Instead, it harbors a community of algae, zooplankton, and debris in the bladders that indicates U. purpurea favors a mutualistic interaction in place of a predator–prey relationship.
Peter Geoffrey Taylor (1926–2011) was a British botanist who worked at Royal Botanic Gardens, Kew throughout his career in botany. Taylor was born in 1926 and joined the staff of the herbarium at Kew in 1948. He published his first new species, Utricularia pentadactyla, in 1954. In 1973, Taylor was appointed curator of the orchid division of the herbarium and, according to Kew, "under his direction, orchid taxonomy was revitalised and its horticultural contacts strengthened."
Carnivorous plants are plants that derive some or most of their nutrients from trapping and consuming animals or protozoans, typically insects and other arthropods, and occasionally small mammals and birds. They still generate all of their energy from photosynthesis. They have adapted to grow in waterlogged sunny places where the soil is thin or poor in nutrients, especially nitrogen, such as acidic bogs. They can be found on all continents except Antarctica, as well as many Pacific islands. In 1875, Charles Darwin published Insectivorous Plants, the first treatise to recognize the significance of carnivory in plants, describing years of painstaking research.
Pinguicula, commonly known as butterworts, is a genus of carnivorous flowering plants in the family Lentibulariaceae. They use sticky, glandular leaves to lure, trap, and digest insects in order to supplement the poor mineral nutrition they obtain from the environment. Of the roughly 80 currently known species, 13 are native to Europe, 9 to North America, and some to northern Asia. The largest number of species is in South and Central America.
Australia has one of the world's richest carnivorous plant floras, with around 187 recognised species from 6 genera.
Genlisea tuberosa is a carnivorous species in the genus Genlisea that is endemic to Brazil and found only in campos rupestres vegetation. Lacking any roots, it has unpigmented bundles of "rootlike" subterranean organs, technically leaves, which attract, trap, and digest protozoans. This species is unique in the genus in its formation of tubers. As of 2014, Genlisea tuberosa has the smallest known genome of any flowering plant, at 61 Mbp, or 61,000,000 base pairs.
Pinguicula hemiepiphytica is a tropical carnivorous plant species native to the cloud forests of Oaxaca, Mexico. It was first identified in 1991 and is one of the few epiphytic species in the genus.