The flowering plants known as angiosperms, Angiospermae or Magnoliophyta, are the most diverse group of land plants, with 64 orders, 416 families 13,164 known genera and c. 369,000 known species. Like gymnosperms, angiosperms are seed-producing plants. However, they are distinguished from gymnosperms by characteristics including flowers, endosperm within the seeds, the production of fruits that contain the seeds. Etymologically, angiosperm means a plant; the term comes from the Greek words sperma. The ancestors of flowering plants diverged from gymnosperms in the Triassic Period, 245 to 202 million years ago, the first flowering plants are known from 160 mya, they diversified extensively during the Early Cretaceous, became widespread by 120 mya, replaced conifers as the dominant trees from 100 to 60 mya. Angiosperms differ from other seed plants in several ways, described in the table below; these distinguishing characteristics taken together have made the angiosperms the most diverse and numerous land plants and the most commercially important group to humans.
Angiosperm stems are made up of seven layers. The amount and complexity of tissue-formation in flowering plants exceeds that of gymnosperms; the vascular bundles of the stem are arranged such that the phloem form concentric rings. In the dicotyledons, the bundles in the young stem are arranged in an open ring, separating a central pith from an outer cortex. In each bundle, separating the xylem and phloem, is a layer of meristem or active formative tissue known as cambium. By the formation of a layer of cambium between the bundles, a complete ring is formed, a regular periodical increase in thickness results from the development of xylem on the inside and phloem on the outside; the soft phloem becomes crushed, but the hard wood persists and forms the bulk of the stem and branches of the woody perennial. Owing to differences in the character of the elements produced at the beginning and end of the season, the wood is marked out in transverse section into concentric rings, one for each season of growth, called annual rings.
Among the monocotyledons, the bundles are more numerous in the young stem and are scattered through the ground tissue. They once formed the stem increases in diameter only in exceptional cases; the characteristic feature of angiosperms is the flower. Flowers show remarkable variation in form and elaboration, provide the most trustworthy external characteristics for establishing relationships among angiosperm species; the function of the flower is to ensure fertilization of the ovule and development of fruit containing seeds. The floral apparatus may arise terminally from the axil of a leaf; as in violets, a flower arises singly in the axil of an ordinary foliage-leaf. More the flower-bearing portion of the plant is distinguished from the foliage-bearing or vegetative portion, forms a more or less elaborate branch-system called an inflorescence. There are two kinds of reproductive cells produced by flowers. Microspores, which will divide to become pollen grains, are the "male" cells and are borne in the stamens.
The "female" cells called megaspores, which will divide to become the egg cell, are contained in the ovule and enclosed in the carpel. The flower may consist only of these parts, as in willow, where each flower comprises only a few stamens or two carpels. Other structures are present and serve to protect the sporophylls and to form an envelope attractive to pollinators; the individual members of these surrounding structures are known as petals. The outer series is green and leaf-like, functions to protect the rest of the flower the bud; the inner series is, in general, white or brightly colored, is more delicate in structure. It functions to attract bird pollinators. Attraction is effected by color and nectar, which may be secreted in some part of the flower; the characteristics that attract pollinators account for the popularity of flowers and flowering plants among humans. While the majority of flowers are perfect or hermaphrodite, flowering plants have developed numerous morphological and physiological mechanisms to reduce or prevent self-fertilization.
Heteromorphic flowers have short carpels and long stamens, or vice versa, so animal pollinators cannot transfer pollen to the pistil. Homomorphic flowers may employ a biochemical mechanism called self-incompatibility to discriminate between self and non-self pollen grains. In other species, the male and female parts are morphologically separated, developing on different flowers; the botanical term "Angiosperm", from the Ancient Greek αγγείον, angeíon and σπέρμα, was coined in the form Angiospermae by Paul Hermann in 1690, as the name of one of his primary divisions of the plant kingdom. This included flowering plants possessing seeds enclosed in capsules, distinguished from his Gymnospermae, or flowering plants with achenial or schizo-carpic fruits, the whole fruit or each of its pieces being here regarded as a seed and naked; the term and its antonym were maintained by Carl Linnaeus with the same sense, but with restricted application, in the names of the orders of his class Didynamia. Its use with any
Commelinaceae is a family of flowering plants. In less formal contexts, the group is referred to as the dayflower spiderwort family, it is one of five families in the order Commelinales and by far the largest of these with about 731 known species in 41 genera. Well known genera include Tradescantia; the family is diverse in both the Old World tropics and the New World tropics, with some genera present in both. The variation in morphology that of the flower and inflorescence, is considered to be exceptionally high amongst the angiosperms; the family has always been recognized by most taxonomists. The APG III system of 2009 recognizes this family, assigns it to the order Commelinales in the clade commelinids in the monocots; the family counts several hundred species of herbaceous plants. Many are cultivated as ornamentals; the stems of these plants are well-developed, swollen at the nodes. Flowers are short-lived, lasting for a day or less; the flowers of Commelinaceae are ephemeral, lack nectar, offer only pollen as a reward to their pollinators.
Most species are hermaphroditic, meaning each flower contains male and female organs, or andromonoecious, meaning that both bisexual and male flowers occur on the same plant. Floral dimorphism may be accompanied by variable pedicel length, filament length and/or curvature, or stamen number and/or position. Species tend to have specific flowering seasons, though local environmental factors tend to effect exact timing, sometimes considerably. Species tend to flower at a specific time of day as well, with these periods being well defined enough to isolate different species reproductively. Furthermore, some species exhibit differential opening times for male and bisexual flowers. Commelinaceae flowers tend to deceive pollinators by appearing to offer a larger reward than is present; this is accomplished with various adaptations such as yellow hairs or broad anther connectives that mimic pollen, or staminodes that lack pollen but appear like fertile stamens. Plants in the Commelinaceae are perennials, but a smaller number of species are annuals.
They are always terrestrial except for plants in the genus Cochliostema. Plants have an erect or scrambling but ascending habit spreading by rooting at the nodes or by stolons; some have rhizomes, the genera Streptolirion and some species of Spatholirion are climbers. The roots are either fibrous or form tubers. Leaves form sheaths at their bases that surround the stem, much like the leaves of grasses, except that the sheaths are closed and do not have a ligule; the leaves may be two-ranked or spirally arranged. The leaf blades are simple and entire, they sometimes narrow at the base, they are succulent; the way in which the leaves unfurl from bud is a distinctive feature of the family: it is termed involute, means that the margins at the leaf base are rolled in when they first emerge. However, some groups are convolute; the inflorescences occur either as a terminal shoot at the top of the plant, or as terminal and axillary shoots arising from lower nodes, or as only axillary shoots that pierce through the leaf sheath such as in Coleotrype and Amischotolype.
The inflorescence is classed as a thyrse, each subunit is made up of cincinni. Inflorescences or their subunit are sometimes enclosed in a leaf-like bract called a spathe. Flowers can have many planes of symmetry, they remain open for only a few hours after opening. The flowers are all bisexual, but some species have both male and bisexual flowers, the single species Callisia repens has bisexual and female flowers, some have bisexual and female flowers. Nectaries are not found in any species within the family. There are always three sepals, although they may be equal or unequal, unfused or basally fused, petal-like or green. There are always three petals, but these may be equal or in two forms, free or basally fused, white or coloured; the petals are sometimes clawed, meaning they narrow to stalk at the base where they attach to the rest of the flower. There are always six stamens in two whorls, but these occur in a myriad of arrangements and forms, they may be all fertile and equal or unequal. Staminodes can alternate with the fertile stamens or they can all occur in the upper or lower hemisphere of the flower.
The stalks of the stamens are bearded in many genera, although in some of these only some are bearded while others are hairless. Sometimes one to three stamens are absent altogether. Pollen is released from slits that open on the sides of the anthers from top to bottom, but some species have pores that open at the tips; the Commelinaceae are a well supported monophyletic group according to the analysis of Burns. Et al.. The following is a phylogeny, or evolutionary tree, of most of the genera in Commelinaceae based on DNA sequences from the plastid gene rbcL All clades shown have 80% bootstrap support or better. List of foliage plant diseases links at CSDL
The genus Thymus contains about 350 species of aromatic perennial herbaceous plants and subshrubs to 40 cm tall in the family Lamiaceae, native to temperate regions in Europe, North Africa and Asia. Stems tend to be narrow or wiry. Thyme flowers are in dense terminal heads, with an uneven calyx, with the upper lip three-lobed, white, or purple. Several members of the genus are cultivated as culinary herbs or ornamentals, when they are called thyme after its best-known species, Thymus vulgaris or common thyme. Thymus species are used as food plants by the larvae of some Lepidoptera insect species, including Chionodes distinctella and the Coleophora case-bearers C. lixella, C. niveicostella, C. serpylletorum, C. struella. A considerable amount of confusion has existed in the naming of thymes. Many nurseries use common names rather than binomial names. For example golden thyme, lemon thyme, creeping thyme can all refer to more than one cultivar; some confusion remains over the naming and taxonomy of some species, Margaret Easter has compiled a list of synonyms for cultivated species and cultivars.
The most common classification is that used by Jalas, in eight sections: Micantes: Iberian Peninsula and north Africa, includes T. caespititius Mastichina: Iberian Peninsula, includes T. mastichina Piperella: Monotypic section confined to the vicinity of Valencia, Spain Teucrioides: Balkan Peninsula Pseudothymbra: Iberian Peninsula and north Africa, includes T. cephalotos, T. longiflorus and T. membranaceus Thymus: Western Mediterranean region, includes T. camphoratus, T. carnosus, T. hyemalis, T. vulgaris and T. zygis Hyphodromi: Throughout the Mediterranean region, includes T. cilicicus and T. comptus Serpyllum: The largest section, throughout whole region, apart from Madeira and Azores, includes T. comosus, T. doerfleri, T. herba-barona, T. longicaulis, T. pannonicus, T. praecox, T. pulegioides, T. quinquecostatus, T. richardii, T. serpyllum, T. sibthorpii and T. thracicus About 350 species, including: Easter M. Thymus University of Melbourne: Thymus World Checklist Media related to Thymus at Wikimedia Commons Data related to Thymus at Wikispecies
Johann Christian Mikan
Johann Christian Mikan was an Austrian-Czech botanist and entomologist. He was the son of Joseph Gottfried Mikan. Mikan was a professor of natural history at the University of Prague, he was one of three leading naturalists on the Austrian Brazil Expedition. He wrote Monographia Bombyliorum Bohemiæ, iconibus illustrata in 1796, Entomologische Beobachtungen, Berichtigungen und Entdeckungen in 1797, Delectus Florae et Faunae Brasiliensis, etc. in 1820. Mikan described many new species, including the black lion tamarin; the genus Mikania Willd. was named for his father Joseph Gottfried Mikan, professor of botany and chemistry at the Prague University. Books by J. C. Mikan on WorldCat Anonym 1852 Lotos 2 63–65. Eiselt, J. N. 1836 Geschichte, Systematik und Literatur der Insectenkunde, von den ältesten Zeiten bis auf die Gegenwart. Als Handbuch für den Jünger und als Repertorium für den Meister der Entomologie bearbeitet. Leipzig, C. H. F. Hartmann. Evenhuis, N. L. 1997 Litteratura taxonomica dipterorum.
Volume 1. Leiden. Stearn, T. 1956 Mikan's Faunae Brasiliensis J. Soc. Bibliog. Nat. Hist. 3:135–136 doi:10.3366/jsbnh.19184.108.40.206. 6. Detailed biography in the Neue deutsche Biographie
Wikispecies is a wiki-based online project supported by the Wikimedia Foundation. Its aim is to create a comprehensive free content catalogue of all species. Jimmy Wales stated that editors are not required to fax in their degrees, but that submissions will have to pass muster with a technical audience. Wikispecies is available under the GNU Free Documentation License and CC BY-SA 3.0. Started in September 2004, with biologists across the world invited to contribute, the project had grown a framework encompassing the Linnaean taxonomy with links to Wikipedia articles on individual species by April 2005. Benedikt Mandl co-ordinated the efforts of several people who are interested in getting involved with the project and contacted potential supporters in early summer 2004. Databases were evaluated and the administrators contacted, some of them have agreed on providing their data for Wikispecies. Mandl defined two major tasks: Figure out how the contents of the data base would need to be presented—by asking experts, potential non-professional users and comparing that with existing databases Figure out how to do the software, which hardware is required and how to cover the costs—by asking experts, looking for fellow volunteers and potential sponsorsAdvantages and disadvantages were discussed by the wikimedia-I mailing list.
The board of directors of the Wikimedia Foundation voted by 4 to 0 in favor of the establishment of a Wikispecies. The project is hosted at species.wikimedia.org. It was merged to a sister project of Wikimedia Foundation on September 14, 2004. On October 10, 2006, the project exceeded 75,000 articles. On May 20, 2007, the project exceeded 100,000 articles with a total of 5,495 registered users. On September 8, 2008, the project exceeded 150,000 articles with a total of 9,224 registered users. On October 23, 2011, the project reached 300,000 articles. On June 16, 2014, the project reached 400,000 articles. On January 7, 2017, the project reached 500,000 articles. On October 30, 2018, the project reached 600,000 articles, a total of 1.12 million pages. Wikispecies comprises taxon pages, additionally pages about synonyms, taxon authorities, taxonomical publications, institutions or repositories holding type specimen. Wikispecies asks users to use images from Wikimedia Commons. Wikispecies does not allow the use of content.
All Species Foundation Catalogue of Life Encyclopedia of Life Tree of Life Web Project List of online encyclopedias The Plant List Wikispecies, The free species directory that anyone can edit Species Community Portal The Wikispecies Charter, written by Wales
Award of Garden Merit
The Award of Garden Merit is a long-established annual award for plants by the British Royal Horticultural Society. It is based on assessment of the plants' performance under UK growing conditions; the Award of Garden Merit is a mark of quality awarded, since 1922, to garden plants by the United Kingdom, Royal Horticultural Society. Awards are made annually after plant trials intended to judge the plants' performance under UK growing conditions. Trials may last for one or more years, depending on the type of plant being tried out, may be performed at Royal Horticulture Society Garden in Wisley and other gardens or after observation of plants in specialist collections. Trial reports are made available on the website. Awards are reviewed annually in case plants have become unavailable horticulturally, or have been superseded by better cultivars; the award should not be confused with the Royal Horticulture Society's Award of Merit, given to plants deemed'of great merit for exhibition' i.e. for show, not garden, plants.
Since 1989, France has had similar awards called the Mérites de Courson, but these are drawn from a limited number of plants submitted by nurserymen to juries at the twice-yearly Journées des Plantes de Courson and awards are based on the opinions of the jury members as to the plants' performance in French gardens, rather than on extensive trials. The Award of Garden Merit was reviewed in 1992, to increase its prestige. Field trial results gained weight in the assessments and existing AGM plants were reviewed in the light of more recent experience; the AGMs were to be reviewed at 10 year intervals from 1992, but this frequency has been increased to annually. The 2012/13 review, with advice from experts such as Royal Horticultural Society's plant committees, specialist societies, Plant Heritage National Collection holders and others, resulted in many changes. Nearly 1,900 plants lost more than 1,400 plants gained awards. Plants may be added to the Royal Horticultural Society'Sunset List' for rescission for several reasons, including unavailability to gardeners, better plants becoming available, affliction by pests or diseases, or insufficient uniformity.
To qualify for an Award of Garden Merit, a plant must be available horticulturally must be of outstanding excellence for garden decoration or use must be of good constitution must not require specialist growing conditions or care must not be susceptible to any pest or disease must not be subject to an unreasonable degree of reversion. The "Award of Garden Merit" symbol represents a cup-shaped trophy with handles, it is cited together with a hardiness rating as follows: H1 Requires a heated glasshouse H1a Warmer than 15C/59F: tropical plants for indoors and heated greenhouses H1b 10C/50F to 15C/59F: subtropical plants for indoors and heated greenhouses H1c 5C/41F to 10C/50F: warm temperate plants that can go outdoors in summer H2 1C/34F to 5C/41F: plants that need a frost-free greenhouse in winter H3 -5C/23F to 1C/34F: hardy outside in some regions or situations, or which - while grown outside in summer - need frost protection in winter H4 -10C/14F to -5C/23F: plants hardy outside in most of the UK in an average winter H5 -15C/5F to -10C/14F: plants hardy outside in most of the UK in severe winters H6 -20C/-4F to -15C/5F: plants hardy outside in the UK and northern Europe H7 Colder than -20C/-4F: plants hardy outside in the severest European climates List of Award of Garden Merit flowering cherries List of Award of Garden Merit magnolias List of Award of Garden Merit roses List of Award of Garden Merit sweet peas RHS Plant Finder 2005–2006, Dorling Kindersley ISBN 1-4053-0736-6 The Royal Horticultural Society's website - Search facility for AGM plants RHS AGM Plant Awards RHS Plant Committees Search for AGM plants The Royal Horticultural Society Complete AGM lists
South America is a continent in the Western Hemisphere in the Southern Hemisphere, with a small portion in the Northern Hemisphere. It may be considered a subcontinent of the Americas, how it is viewed in the Spanish and Portuguese-speaking regions of the Americas; the reference to South America instead of other regions has increased in the last decades due to changing geopolitical dynamics. It is bordered on the west on the north and east by the Atlantic Ocean, it includes twelve sovereign states, a part of France, a non-sovereign area. In addition to this, the ABC islands of the Kingdom of the Netherlands and Tobago, Panama may be considered part of South America. South America has an area of 17,840,000 square kilometers, its population as of 2016 has been estimated at more than 420 million. South America ranks fourth in fifth in population. Brazil is by far the most populous South American country, with more than half of the continent's population, followed by Colombia, Argentina and Peru. In recent decades Brazil has concentrated half of the region's GDP and has become a first regional power.
Most of the population lives near the continent's western or eastern coasts while the interior and the far south are sparsely populated. The geography of western South America is dominated by the Andes mountains. Most of the continent lies in the tropics; the continent's cultural and ethnic outlook has its origin with the interaction of indigenous peoples with European conquerors and immigrants and, more locally, with African slaves. Given a long history of colonialism, the overwhelming majority of South Americans speak Portuguese or Spanish, societies and states reflect Western traditions. South America occupies the southern portion of the Americas; the continent is delimited on the northwest by the Darién watershed along the Colombia–Panama border, although some may consider the border instead to be the Panama Canal. Geopolitically and geographically all of Panama – including the segment east of the Panama Canal in the isthmus – is included in North America alone and among the countries of Central America.
All of mainland South America sits on the South American Plate. South America is home to Angel Falls in Venezuela. South America's major mineral resources are gold, copper, iron ore and petroleum; these resources found in South America have brought high income to its countries in times of war or of rapid economic growth by industrialized countries elsewhere. However, the concentration in producing one major export commodity has hindered the development of diversified economies; the fluctuation in the price of commodities in the international markets has led to major highs and lows in the economies of South American states causing extreme political instability. This is leading to efforts to diversify production to drive away from staying as economies dedicated to one major export. South America is one of the most biodiverse continents on earth. South America is home to many interesting and unique species of animals including the llama, piranha, vicuña, tapir; the Amazon rainforests possess high biodiversity, containing a major proportion of the Earth's species.
Brazil is the largest country in South America, encompassing around half of the continent's land area and population. The remaining countries and territories are divided among three regions: The Andean States, the Guianas and the Southern Cone. Traditionally, South America includes some of the nearby islands. Aruba, Curaçao, Trinidad and the federal dependencies of Venezuela sit on the northerly South American continental shelf and are considered part of the continent. Geo-politically, the island states and overseas territories of the Caribbean are grouped as a part or subregion of North America, since they are more distant on the Caribbean Plate though San Andres and Providencia are politically part of Colombia and Aves Island is controlled by Venezuela. Other islands that are included with South America are the Galápagos Islands that belong to Ecuador and Easter Island, Robinson Crusoe Island, Chiloé and Tierra del Fuego. In the Atlantic, Brazil owns Fernando de Noronha and Martim Vaz, the Saint Peter and Saint Paul Archipelago, while the Falkland Islands are governed by the United Kingdom, whose sovereignty over the islands is disputed by Argentina.
South Georgia and the South Sandwich Islands may be associate