44-453: Droseraceae is a family of carnivorous flowering plants , also known as the sundew family. It consists of approximately 180 species in three extant genera, the vast majority being in the sundew genus Drosera . The family also contains the well-known Venus flytrap ( Dionaea muscipula ) and the more obscure waterwheel plant ( Aldrovanda vesiculosa ), both of which are the only living species of their respective genera. Representatives of
88-457: A consensus over time. The naming of families is codified by various international bodies using the following suffixes: The taxonomic term familia was first used by French botanist Pierre Magnol in his Prodromus historiae generalis plantarum, in quo familiae plantarum per tabulas disponuntur (1689) where he called the seventy-six groups of plants he recognised in his tables families ( familiae ). The concept of rank at that time
132-446: A family, yet in the realm of plants, these classifications often rely on both the vegetative and reproductive characteristics of plant species. Taxonomists frequently hold varying perspectives on these descriptions, leading to a lack of widespread consensus within the scientific community for extended periods. The continual publication of new data and diverse opinions plays a crucial role in facilitating adjustments and ultimately reaching
176-553: A liquor-like dew, hanging on its fringed leaves, and continuing in the hottest part of the day, exposed to the sun." In 1867, Bentham and Hooker placed six genera in the Droseraceae: Dionaea, Aldrovanda, Drosera, Drosophyllum, Byblis, and Roridula . Although these genera had significant differences in leaf and flower morphologies, they were grouped together on the basis of insect traps that appeared to be homologous. In 1922, Byblis and Roridula were moved into
220-725: A new family, the Byblidaceae (and later further split out, forming the Roridulaceae). In the 1990s, both morphological and molecular evidence began to build that Drosophyllum differed from the other genera in the Droseraceae, Drosophyllum , another monotypic genus ( Drosophyllum lusitanicum being the only species ) , exhibits a flypaper-type trap similar to those of Drosera , but Drosophyllum does not actively curl its leaves to envelop captured prey animals. This important morphological distinction led researchers to question
264-406: A slightly acidic pH (around 6). It can be found floating amongst Juncus , reeds , and even rice . The Waterwheel (Aldrovanda vesiculosa) thrives in a range of aquatic habitats, including small fens, peat-bog pools, billabongs, lakes, lagoons, and river deltas. It prefers oligo-mesotrophic and dystrophic systems with low nutrient levels. These plants are commonly found in shallow backwaters or
308-481: A snap-trap similar to that of the Venus flytrap , except that it is smaller and located underwater. These traps, which are twisted so that the trap openings point outward, are lined on the inside by a fine coating of trigger hairs, snapping shut in response to contact with aquatic invertebrates and trapping them. The closing of this trap takes 10–20 milliseconds, making it one of the fastest examples of plant movement in
352-460: A tight bud of protective leaves which, being heavier and having released flotational gases, breaks off the mother plant and sinks to the water bottom, where temperatures are stable and warmer. Here it can withstand temperatures as low as −15 °C (5 °F). In the wild, Aldrovanda turions have been observed to have a relatively low rate of successful sinking. Those nutritious turions that fail to sink are then grazed by waterfowl or are killed by
396-732: Is aquatic and is smaller and faster than that of Dionaea . In addition, while two stimuli are required to close a trap in Dionaea , only one is required in Aldrovanda . The trap of Aldrovanda closes about ten times faster than that of Dionaea . The type genus for the Droseraceae is Drosera , which was described and named by Linnaeus in 1753. The name was derived from the Greek word "droseros", meaning "dewy" or "drops of water". The Principia Botanica , published in 1787, states "Sun-dew ( Drosera ) derives its name from small drops of
440-471: Is spread mainly through the movement of waterfowl: plants sticking to the feet of a bird are transported to the next aquatic destination on the bird's route. As a result, most Aldrovanda populations are located along avian migratory routes. Throughout the last century the species has become increasingly rare, listed as extinct in an increasingly large number of countries. In the 1970s, carnivorous plant hobbyists introduced this species to small backyard ponds in
484-483: The Genera Plantarum of George Bentham and Joseph Dalton Hooker this word ordo was used for what now is given the rank of family. Families serve as valuable units for evolutionary, paleontological, and genetic studies due to their relatively greater stability compared to lower taxonomic levels like genera and species. Aldrovanda vesiculosa Aldrovanda vesiculosa , commonly known as
SECTION 10
#1732801013053528-555: The United States in the states of New Jersey , Virginia , and the Catskills of New York , and they may be a potentially invasive species due to their effects on aquatic invertebrates. The waterwheel plant faces significant conservation threats related to habitat degradation and human-induced modifications. Residential and commercial development, along with agricultural and aquacultural activities, pose immediate risks to
572-424: The eastern United States . It is kept by hobbyists. Aldrovanda vesiculosa is a rootless aquatic plant . Seedlings develop a short protoroot; however, this fails to develop further and senesces. The plant consists of floating stems reaching a length of 6–40 cm (2–16 in). The 2–3 mm ( 1 ⁄ 16 – 1 ⁄ 8 in) trap leaves grow in whorls of between 5 and 9 in close succession along
616-581: The kingdom . This trapping is only possible in warm conditions of at least 20 °C (68 °F). Each trap is surrounded by between four and six 6–8 millimetres ( 1 ⁄ 4 – 3 ⁄ 8 in) long bristles that prevent triggering of traps by debris in the water. A. vesiculosa is able to grow in nutrient-poor habitats not only due to its carnivory, but also due to its ability to re-utilize nutrients from senesced shoots, and its high affinity for mineral nutrients in water. The small, solitary white flowers of A. vesiculosa are supported above
660-406: The waterwheel plant , is the sole extant species in the flowering plant genus Aldrovanda of the family Droseraceae . The plant captures small aquatic invertebrates using traps similar to those of the Venus flytrap . The traps are arranged in whorls around a central, free-floating stem, giving rise to the common name. This is one of the few plant species capable of rapid movement . While
704-473: The "core" Caryophyllales, such as Cactaceae and Amaranthaceae and is sister to the Polygonineae – the "non-core" Caryophyllales. This non-core clade is where Droseraceae is placed. Recent molecular and biochemical evidence suggests the carnivorous taxa in the order Caryophyllales (the families Droseraceae, Drosophyllaceae , Nepenthaceae , and the species Triphyophyllum peltatum ) all belong to
748-496: The Droseraceae are able to supplement their nutrient intake, especially that of nitrogen, by capturing and digesting small animals such as insects. In this way, these plants are able to thrive in nutrient-deficient areas, such as sphagnum bogs . Drosera is one of the largest genera of carnivorous plants, and individual species vary extensively in their specific morphology. Common to all members of Drosera are highly modified leaves lined with tentacle-like glandular trichomes . At
792-679: The Droseraceae are found on all continents except Antarctica. Droseraceae are carnivorous herbaceous plants that may be annuals or perennials. Their leaves are alternate and adaxially circinate , with at least one leaf surface containing hairs with mucilage-producing glands at the tip. Their flowers are bisexual, usually with three carpels and five sepals , petals and stamens . Their pollen grains are triporate or multiporate and released in tetrads . Despite being carnivorous, their flowers are insect-pollinated, typically with white to purple flowers that close at night. They produce small seeds that are dispersed by wind and water. Most of
836-405: The Droseraceae began with simple flypaper traps, followed by movement of tentacles in some Drosera -like species, followed by movement of leaves, leading eventually to the development of snap-traps in Dionaea and Aldrovanda by increasing the speed of the leaf movements and altering the morphology of the leaves. Due to the sister relationship of Dionaea and Aldrovanda, it is likely that
880-573: The Drosophyllaceae. This left only the three genera ( Dionaea, Aldrovanda, Drosera ) that are classified as Droseraceae today. Despite some debate, taxonomists have tended to include at least two of these three genera, and, in general, all three, in this family since at least 1906. Separate families for Dionaea and Aldrovanda have been proposed in the past. These were Dionaecae, proposed in 1933, and Aldrovandaceae, proposed in 1949. Ultimately, molecular and morphological evidence support
924-514: The book's morphological section, where he delved into discussions regarding the vegetative and generative aspects of plants. Subsequently, in French botanical publications, from Michel Adanson 's Familles naturelles des plantes (1763) and until the end of the 19th century, the word famille was used as a French equivalent of the Latin ordo (or ordo naturalis ). In zoology ,
SECTION 20
#1732801013053968-468: The end of each trichome, a bead of highly viscous mucilage is secreted, which resembles a drop of dew. The mucilage is a fairly pure aqueous solution of acidic polysaccharides with high molecular weights, which makes the mucilage not only highly viscous, but also very sticky, so much so, a single drop of mucilage may be stretched to lengths of up to a meter and cover one million times its original surface area. Insects and other prey animals are attracted by
1012-490: The exterior of the trap is concave to one where the exterior is convex. This movement can begin as soon as 0.4 seconds after stimulation and can be completed after one second. Aldrovanda vesiculosa , also called the waterwheel plant, is a free-floating, rootless, aquatic plant. It is less well-known than its relative Dionaea muscipula , but the two have similar trap structures. In 1875, Darwin described Aldrovanda as "a miniature aquatic Dionaea ". The trap of Aldrovanda
1056-540: The family as a rank intermediate between order and genus was introduced by Pierre André Latreille in his Précis des caractères génériques des insectes, disposés dans un ordre naturel (1796). He used families (some of them were not named) in some but not in all his orders of "insects" (which then included all arthropods ). In nineteenth-century works such as the Prodromus of Augustin Pyramus de Candolle and
1100-487: The genus Aldrovanda is now monotypic, up to 19 extinct species are known in the fossil record. While the species displays a degree of morphological plasticity between populations, A. vesiculosa possesses a very low genetic diversity across its entire range. A. vesiculosa has declined over the last century to only 50 confirmed extant populations worldwide. These are spread across Europe, Africa, Asia, and Australia. However, potentially invasive populations exist in
1144-596: The inclusion of all three, confirming that the Droseraceae are a monophyletic group. Molecular evidence also shows that the two genera with traps that snap shut ( Dionaea and Aldrovanda ) are more closely related to each other than to Drosera , suggesting snap traps evolved only once. The family Droseraceae is part of the order Caryophyllales in the Superasterid clade within the core eudicots . The family totals nearly 200 species. Caryophyllales are divided into two major suborders: Caryophyllineae , which contains
1188-498: The littoral zones of larger lakes, where they face less competition from other aquatic species and where water levels remain relatively stable throughout the growing season. The Waterwheel is highly intolerant of habitat degradation, and even minor changes in water chemistry can lead to local extinction. Aldrovanda vesiculosa was first mentioned and illustrated in 1691 by Leonard Plukenet , based on collections made in India . He named
1232-440: The members of Droseraceae are contained in the genus Drosera , the sundews. Both Dionaea and Aldrovanda have only one extant species. Drosera species trap prey by secreting a sticky substance from hairs on their leaves. Dionaea and Aldrovanda both use snap-traps that close rapidly when the leaves are disturbed. Dionaea is terrestrial, while Aldrovanda is strictly aquatic. Like carnivorous plants of other families,
1276-409: The most wonderful in the world." The leaves of Dionaea are also highly modified and form a "snap-trap" that quickly shuts when a stimulus is detected. Three large trichomes extend outward on the inner surface of the trap. Two of these three hairs must be stimulated within a certain amount of time to trigger the trap. The trap closes as the result of a flipping of the trap lobes from a position where
1320-485: The onset of frost. In spring when water temperatures rise above 12–15 °C (54–59 °F), turions reduce their density and float to the top of the water, where they germinate and resume growth. Non-dormant turion-like organs can also form in response to summer drought. Aldrovanda vesiculosa is the second most widely distributed carnivorous plant species, only behind members of the genus Utricularia , native to Europe , Asia , Africa , and Australia . Aldrovanda
1364-490: The plant's central stem. The actual traps are held by petioles which have air sacs that aid in flotation. One end of the stem continually grows while the other end dies off. Growth is quite rapid ( 4–9 mm ( 3 ⁄ 16 – 3 ⁄ 8 in) per day in Japanese populations ), so that in optimal conditions a new whorl is produced once or more each day. The actual traps consist of two lobes which fold together to form
Droseraceae - Misplaced Pages Continue
1408-426: The potential to disrupt the waterwheel plant's habitats and populations. While the extent and effects of illegal trade remain uncertain, it is believed that some illegal activities involving Aldrovanda vesiculosa may occur. This potential threat adds complexity to the conservation challenges faced by the species. A. vesiculosa prefers clean, shallow, warm, standing water with bright light, low nutrient levels, and
1452-424: The prey for digestion. Four Drosera subgenera are recognized today: subgenus Regiae and subgenus Arcturia are each monotypic ( D. regia and D. arcturi, respectively), and the remaining Drosera are divided into two clades, subgenus Ergaleium and subgenus Drosera . Dionaea muscipula , better known as the Venus flytrap , is a globally famous carnivorous plant and according to Charles Darwin , "one of
1496-491: The ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae , but that family is commonly referred to as the "walnut family". The delineation of what constitutes a family— or whether a described family should be acknowledged— is established and decided upon by active taxonomists . There are not strict regulations for outlining or acknowledging
1540-414: The same clade , which does not consist only of carnivorous plants, but also of some noncarnivorous plants such as those in the family Ancistrocladaceae . The fossil record of Droseraceae is the richest of any carnivorous plant family. Fossil pollen has been attributed to several extant , as well as extinct , genera, although some are of questionable validity. Darwin concluded that carnivory in plants
1584-431: The smell of this mucilage and become stuck in it. Such snares are termed "flypaper traps", but the trapping mechanism of sundews is often erroneously described as "passive". In fact, sundew traps are quite active and sensitive, and the disturbance of one or a few trichomes quickly triggers an action potential that stimulates the rapid movement of other trichomes toward the prey. The leaf then curls in on itself, enveloping
1628-464: The snap-trap mechanism only evolved once, but it is unknown if the common ancestor was terrestrial or aquatic. Family (biology) Family ( Latin : familia , pl. : familiae ) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy . It is classified between order and genus . A family may be divided into subfamilies , which are intermediate ranks between
1672-544: The species. The impacts of these activities on the plant's aquatic habitats are of particular concern. Across Europe, the species is confronted by several environmental challenges, as identified by the Commission of the European Union. Acidification, canalization, drainage, eutrophication, pollution, and various forms of habitat modification are highlighted as threats. These changes in the natural environment have
1716-404: The tips continue to grow and the old ends die off and separate. Due to the rapid growth rate of this species, countless new plants can be produced in a short period of time in this fashion. Winter-hardy Aldrovanda form turions as a frost survival strategy. At the onset of winter, the growth tip starts producing highly reduced non-carnivorous leaves on a severely shortened stem. This results in
1760-559: The validity of this taxon's placement in Droseraceae. Other significant trait differences in Drosophyllum include pollen structure, trichome anatomy, and a woody stem with a deep taproot. Ultimately, Drosophyllum was shown to be more closely related to the carnivorous liana Triphyophyllum and the noncarnivorous liana Ancistrocladus , and is, thus, classified elsewhere (to be specific, its own monotypic family Drosophyllaceae ). and APG III (2009) placed it into its own family,
1804-666: The water by short peduncles which arise from whorl axes. The flower only opens for a few hours, after which the structure is brought back beneath the water for seed production. The seeds are cryptocotylar: the cotyledons remain hidden within the seed coat and serve as an energy store for the seedling. Flowering, however, is rare in temperate regions and poorly successful in terms of fruit and seed development. Aldrovanda vesiculosa reproduces most often through vegetative reproduction . In favourable conditions, adult plants will produce an offshoot every 3–4 cm ( 1 + 1 ⁄ 8 – 1 + 5 ⁄ 8 in), resulting in new plants as
Droseraceae - Misplaced Pages Continue
1848-406: Was convergent , writing in 1875 that Utricularia and Nepenthes were not "at all related to the Droseraceae". This remained a subject of debate for over a century. In 1960, Leon Croizat concluded that carnivory was monophyletic, and placed all the carnivorous plants together at the base of the angiosperms. Molecular studies over the past 30 years have led to a wide consensus that Darwin
1892-424: Was correct, with studies showing that carnivory evolved at least six times in the angiosperms, and that trap designs such as pitcher traps and flypaper traps are analogous rather than homologous. The origin of carnivory within the ancestors of the Droseraceae has been dated to 85.6 million years ago, with the evolution of snap-traps dated to 48 million years ago. Researchers have hypothesized that carnivory in
1936-488: Was not yet settled, and in the preface to the Prodromus Magnol spoke of uniting his families into larger genera , which is far from how the term is used today. In his work Philosophia Botanica published in 1751, Carl Linnaeus employed the term familia to categorize significant plant groups such as trees , herbs , ferns , palms , and so on. Notably, he restricted the use of this term solely within
#52947