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60-675: Hyphaene is a genus of palms native to Africa , Madagascar , the Middle East , and the Indian subcontinent . The genus includes the Doum palm ( H. thebaica ). They are unusual among palms in having regular naturally branched trunks; most other palms are single-stemmed from the ground. In Swahili, it is called "koma". This palm -related article is a stub . You can help Misplaced Pages by expanding it . Arecaceae The Arecaceae ( / ˌ ær ə ˈ k eɪ s i . iː , - ˌ aɪ / )

120-407: A clustering habit results. Exclusively sympodial genera include many of the rattans , Guihaia , and Rhapis . Several palm genera have both solitary and clustering members. Palms which are usually solitary may grow in clusters and vice versa. Palms have large, evergreen leaves that are either palmately ('fan-leaved') or pinnately ('feather-leaved') compound and spirally arranged at the top of

180-538: A hypanthodium, which bears numerous flowers on the inside of a convex or involuted compound receptacle. The genus Euphorbia has cyathia (sing. cyathium ), usually organised in umbels. Some species have inflorescences reduced to composite flowers or pseudanthia , in which case it is difficult to differentiate between inflorescences and single flowers. Genes that shape inflorescence development have been studied at great length in Arabidopsis . LEAFY (LFY)

240-463: A large amount of the human diet and several other human uses, both by absolute amount produced and by number of species domesticated . This is far higher than almost any other plant family, sixth out of domesticated crops in the human diet, and first in total economic value produced – sharing the top spot with the Poaceae and Fabaceae . These human uses have also spread many Arecaceae species around

300-420: A panicle. The family Asteraceae is characterised by a highly specialised head technically called a calathid (but usually referred to as 'capitulum' or 'head'). The family Poaceae has a peculiar inflorescence of small spikes ( spikelets ) organised in panicles or spikes that are usually simply and improperly referred to as spike and panicle . The genus Ficus ( Moraceae ) has an inflorescence called

360-448: A peduncle. Any flower in an inflorescence may be referred to as a floret , especially when the individual flowers are particularly small and borne in a tight cluster, such as in a pseudanthium . The fruiting stage of an inflorescence is known as an infructescence . Inflorescences may be simple (single) or complex ( panicle ). The rachis may be one of several types, including single, composite, umbel, spike or raceme . In some species

420-464: A plant that bears a cluster of flowers in a specific pattern. Inflorescences are described by many different characteristics including how the flowers are arranged on the peduncle, the blooming order of the flowers, and how different clusters of flowers are grouped within it. These terms are general representations as plants in nature can have a combination of types. Because flowers facilitate plant reproduction , inflorescence characteristics are largely

480-413: A result of natural selection . The stem holding the whole inflorescence is called a peduncle . The main axis (also referred to as major stem) above the peduncle bearing the flowers or secondary branches is called the rachis . The stalk of each flower in the inflorescence is called a pedicel . A flower that is not part of an inflorescence is called a solitary flower and its stalk is also referred to as

540-578: A single or a cluster of flower(s) is located at the axil of a bract, the location of the bract in relation to the stem holding the flower(s) is indicated by the use of different terms and may be a useful diagnostic indicator. Typical placement of bracts include: Metatopic placement of bracts include: There is no general consensus in defining the different inflorescences. The following is based on Focko Weberling 's Morphologie der Blüten und der Blütenstände (Stuttgart, 1981). The main groups of inflorescences are distinguished by branching. Within these groups,

600-402: A spicate (spike-like) inflorescence that is commonly called a spike . Simple inflorescences are the basis for compound inflorescences or synflorescences . The single flowers are there replaced by a simple inflorescence, which can be both a racemose or a cymose one. Compound inflorescences are composed of branched stems and can involve complicated arrangements that are difficult to trace back to

660-536: A terminal flower is formed and where flowering starts within the inflorescence. Indeterminate and determinate inflorescences are sometimes referred to as open and closed inflorescences respectively. The indeterminate patterning of flowers is derived from determinate flowers. It is suggested that indeterminate flowers have a common mechanism that prevents terminal flower growth. Based on phylogenetic analyses, this mechanism arose independently multiple times in different species. In an indeterminate inflorescence there

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720-637: A variety of different habitats. Their diversity is highest in wet, lowland forests. South America , the Caribbean , and areas of the South Pacific and southern Asia are regions of concentration. Colombia may have the highest number of palm species in one country. There are some palms that are also native to desert areas such as the Arabian Peninsula and parts of northwestern Mexico. Only about 130 palm species naturally grow entirely beyond

780-609: A water source, and in desert oases such as the date palm . A few palms are adapted to extremely basic lime soils, while others are similarly adapted to extreme potassium deficiency and toxicity of heavy metals in serpentine soils . Palms are a monophyletic group of plants, meaning the group consists of a common ancestor and all its descendants. Extensive taxonomic research on palms began with botanist H.E. Moore , who organized palms into 15 major groups based mostly on general morphological characteristics. The following classification, proposed by N.W. Uhl and J. Dransfield in 1987,

840-505: Is a family of perennial , flowering plants in the monocot order Arecales . Their growth form can be climbers , shrubs , tree -like and stemless plants, all commonly known as palms . Those having a tree-like form are colloquially called palm trees . Currently, 181 genera with around 2,600 species are known, most of which are restricted to tropical and subtropical climates. Most palms are distinguished by their large, compound, evergreen leaves, known as fronds , arranged at

900-407: Is a definite inflorescence that is increasingly more strongly and irregularly branched from the top to the bottom and where each branching has a terminal flower. The so-called cymose corymb is similar to a racemose corymb but has a panicle-like structure. Another type of panicle is the anthela . An anthela is a cymose corymb with the lateral flowers higher than the central ones. A raceme in which

960-543: Is a gene that promotes floral meristem identity, regulating inflorescence development in Arabidopsis. Any alterations in timing of LFY expression can cause formation of different inflorescences in the plant. Genes similar in function to LFY include APETALA1 (AP1). Mutations in LFY, AP1, and similar promoting genes can cause conversion of flowers into shoots. In contrast to LEAFY, genes like terminal flower (TFL) support

1020-508: Is a revision of Moore's classification that organizes palms into 6 subfamilies. A few general traits of each subfamily are listed below. The Phytelephantoideae is the sixth subfamily of Arecaceae in N.W. Uhl and J. Dransfield's 1987 classification. Members of this group have distinct monopodial flower clusters. Other distinct features include a gynoecium with five to 10 joined carpels, and flowers with more than three parts per whorl. Fruits are multiple-seeded and have multiple parts. From

1080-605: Is from Dravidian *aṭ-ay-kkāy ("areca nut"). The suffix -aceae is the feminine plural of the Latin -āceus ("resembling"). Palm originates from Latin palma semantically overlapping with sense of " hand front " (due to similar splayed shape) ultimately from Proto-Indo-European * pl̥h₂meh₂ , a direct descendant folm once existed in Old English. Whether as shrubs, tree-like, or vines, palms have two methods of growth: solitary or clustered. The common representation

1140-434: Is no true terminal flower and the stem usually has a rudimentary end. In many cases the last true flower formed by the terminal bud ( subterminal flower) straightens up, appearing to be a terminal flower. Often a vestige of the terminal bud may be noticed higher on the stem. In determinate inflorescences the terminal flower is usually the first to mature (precursive development), while the others tend to mature starting from

1200-504: Is normally called simply 'umbel'. Another kind of definite simple inflorescence is the raceme-like cyme or botryoid ; that is as a raceme with a terminal flower and is usually improperly called 'raceme'. A reduced raceme or cyme that grows in the axil of a bract is called a fascicle . A verticillaster is a fascicle with the structure of a dichasium; it is common among the Lamiaceae . Many verticillasters with reduced bracts can form

1260-496: Is often called "anomalous secondary growth". The Arecaceae are notable among monocots for their height and for the size of their seeds, leaves, and inflorescences. Ceroxylon quindiuense , Colombia's national "tree", is the tallest monocot in the world, reaching up to 60 metres (197 ft) tall. The coco de mer ( Lodoicea maldivica ) has the largest seeds of any plant, 40–50 centimetres (16–20 in) in diameter and weighing 15–30 kilograms (33–66 lb) each ( coconuts are

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1320-405: Is often called a panicle . This definition is very different from that given by Weberling . Compound umbels are umbels in which the single flowers are replaced by many smaller umbels called umbellets . The stem attaching the side umbellets to the main stem is called a ray . The most common kind of definite compound inflorescence is the panicle (of Webeling, or 'panicle-like cyme'). A panicle

1380-683: Is possible north of subtropical climates, and some higher latitude locales such as Ireland, Scotland, England, and the Pacific Northwest feature a few palms in protected locations and microclimates . In the United States , there are at least 12 native palm species, mostly occurring in the states of the Deep South and Florida . Palms inhabit a variety of ecosystems. More than two-thirds of palm species live in humid moist forests, where some species grow tall enough to form part of

1440-460: Is that of a solitary shoot ending in a crown of leaves. This monopodial character may be exhibited by prostrate, trunkless, and trunk-forming members. Some common palms restricted to solitary growth include Washingtonia and Roystonea . Palms may instead grow in sparse though dense clusters. The trunk develops an axillary bud at a leaf node, usually near the base, from which a new shoot emerges. The new shoot, in turn, produces an axillary bud and

1500-408: Is the modified part of the shoot of seed plants where flowers are formed on the axis of a plant. The modifications can involve the length and the nature of the internodes and the phyllotaxis , as well as variations in the proportions, compressions, swellings, adnations , connations and reduction of main and secondary axes. One can also define an inflorescence as the reproductive portion of

1560-566: The Dasypogonaceae . For a phylogenetic tree of the family, see the list of Arecaceae genera . The Arecaceae were the first modern family of monocots to appear in the fossil record around 80 million years ago (Mya), during the late Cretaceous period. The first modern species, such as Nypa fruticans and Acrocomia aculeata , appeared 69 Mya, as evidenced by fossil Nypa pollen. Palms appear to have undergone an early period of adaptive radiation . By 60 Mya, many of

1620-579: The canopy and shorter ones form part of the understory . Some species form pure stands in areas with poor drainage or regular flooding, including Raphia hookeri which is common in coastal freshwater swamps in West Africa. Other palms live in tropical mountain habitats above 1 thousand metres (3 thousand feet), such as those in the genus Ceroxylon native to the Andes . Palms may also live in grasslands and scrublands, usually associated with

1680-647: The Ceroxyloideae and Phytelephantoideae. Studies have suggested the lack of a fully resolved hypothesis for the relationships within the family is due to a variety of factors, including difficulties in selecting appropriate outgroups, homoplasy in morphological character states, slow rates of molecular evolution important for the use of standard DNA markers , and character polarization. However, hybridization has been observed among Orbignya and Phoenix species, and using chloroplast DNA in cladistic studies may produce inaccurate results due to maternal inheritance of

1740-574: The IUCN, and was published in 1996. The rarest palm known is Hyophorbe amaricaulis . The only living individual remains at the Botanic Gardens of Curepipe in Mauritius . Some pests are specialists to particular taxa . Pests that attack a variety of species of palms include: The palm branch was a symbol of triumph and victory in classical antiquity . The Romans rewarded champions of

1800-526: The Middle East and North Africa. A wide range of common products and foods are derived from palms. In contemporary times, palms are also widely used in landscaping. In many historical cultures, because of their importance as food, palms were symbols for such ideas as victory, peace, and fertility. The word Arecaceae is derived from the word areca with the suffix "-aceae". Areca is derived from Portuguese , via Malayalam അടയ്ക്ക ( aṭaykka ), which

1860-580: The Rathayatra carts which carry the deities of Krishna and his family members in the cart festival of Jagganath Puri in India are marked with the emblem of a palm tree. Specifically it is the symbol of Krishna's brother, Baladeva. In 1840, the American geologist Edward Hitchcock (1793–1864) published the first tree-like paleontology chart in his Elementary Geology , with two separate trees of life for

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1920-568: The activity of an inhibitor that prevents flowers from growing on the inflorescence apex (flower primordium initiation), maintaining inflorescence meristem identity. Both types of genes help shape flower development in accordance with the ABC model of flower development . Studies have been recently conducted or are ongoing for homologs of these genes in other flower species. Inflorescence-feeding insect herbivores shape inflorescences by reducing lifetime fitness (how much flowering occurs), seed production by

1980-530: The area. The sale of seeds to nurseries and collectors is another threat, as the seeds of popular palms are sometimes harvested directly from the wild. In 2006, at least 100 palm species were considered endangered, and nine species have been reported as recently extinct. However, several factors make palm conservation more difficult. Palms live in almost every type of warm habitat and have tremendous morphological diversity. Most palm seeds lose viability quickly, and they cannot be preserved in low temperatures because

2040-421: The base of the stem. This pattern is called acropetal maturation. When flowers start to mature from the top of the stem, maturation is basipetal , whereas when the central mature first, maturation is divergent . As with leaves , flowers can be arranged on the stem according to many different patterns. See ' Phyllotaxis ' for in-depth descriptions. Similarly arrangement of leaf in bud is called Ptyxis. When

2100-407: The base. The stamens generally number six, with filaments that may be separate, attached to each other, or attached to the pistil at the base. The fruit is usually a single- seeded drupe (sometimes berry-like) but some genera (e.g., Salacca ) may contain two or more seeds in each fruit. Like all monocots , palms do not have the ability to increase the width of a stem ( secondary growth ) via

2160-471: The chloroplast DNA. Chemical and molecular data from non-organelle DNA, for example, could be more effective for studying palm phylogeny. Recently, nuclear genomes and transcriptomes have been used to reconstruct the phylogeny of palms. This has revealed, for example, that a whole-genome duplication event occurred early in the evolution of the Arecaceae lineage, that was not experienced by its sister clade,

2220-503: The cold kills the embryo. Using botanical gardens for conservation also presents problems, since they can rarely house more than a few plants of any species or truly imitate the natural setting. There is also the risk that cross-pollination can lead to hybrid species. The Palm Specialist Group of the World Conservation Union (IUCN) began in 1984, and has performed a series of three studies to find basic information on

2280-729: The deserts, it also created a more amenable habitat for the people to live in by providing shade and protection from the desert winds. An indication of the importance of palms in ancient times is that they are mentioned more than 30 times in the Bible , and at least 22 times in the Quran . The Torah also references the "70 date palm trees", which symbolize the 70 aspects of Torah that are revealed to those who "eat of its fruit." Arecaceae have great economic importance, including coconut products, oils, dates, palm syrup , ivory nuts, carnauba wax, rattan cane, raffia, and palm wood . This family supplies

2340-542: The different axes. Some passage forms between the obvious ones are commonly admitted. Determinate simple inflorescences are generally called cymose . The main kind of cymose inflorescence is the cyme (pronounced / s aɪ m / ), from the Latin cyma in the sense 'cabbage sprout', from Greek kuma 'anything swollen'). Cymes are further divided according to this scheme: A cyme can also be so compressed that it looks like an umbel. Strictly speaking this kind of inflorescence could be called umbelliform cyme , although it

2400-622: The flowers develop directly from the main stem or woody trunk, rather than from the plant's main shoot. This is called cauliflory and is found across a number of plant families. An extreme version of this is flagelliflory where long, whip-like branches grow from the main trunk to the ground and even below it. Inflorescences form directly on these branches. Plant organs can grow according to two different schemes, namely monopodial or racemose and sympodial or cymose . In inflorescences these two different growth patterns are called indeterminate and determinate respectively, and indicate whether

2460-673: The games and celebrated military successes with palm branches. Early Christians used the palm branch to symbolize the victory of the faithful over enemies of the soul, as in the Palm Sunday festival celebrating the triumphal entry of Jesus Christ into Jerusalem . In Judaism , the palm represents peace and plenty, and is one of the Four Species of Sukkot ; the palm may also symbolize the Tree of Life in Kabbalah . The canopies of

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2520-500: The habitat, and those with small habitat ranges are most vulnerable to them. The harvesting of heart of palm, a delicacy in salads, also poses a threat because it is derived from the palm's apical meristem , a vital part of the palm that cannot be regrown (except in domesticated varieties, e.g. of peach palm ). The use of rattan palms in furniture has caused a major population decrease in these species that has negatively affected local and international markets, as well as biodiversity in

2580-432: The history of the Middle East and North Africa. In the text "Date Palm Products" (1993), W.H. Barreveld wrote: One could go as far as to say that, had the date palm not existed, the expansion of the human race into the hot and barren parts of the "old" world would have been much more restricted. The date palm not only provided a concentrated energy food, which could be easily stored and carried along on long journeys across

2640-432: The inflorescences, and plant density, among other traits. In the absence of these herbivores, inflorescences usually produce more flower heads and seeds. Temperature can also variably shape inflorescence development. High temperatures can impair the proper development of flower buds or delay bud development in certain species, while in others an increase in temperature can hasten inflorescence development. The shift from

2700-469: The main branch. A kind of compound inflorescence is the double inflorescence , in which the basic structure is repeated in the place of single florets. For example, a double raceme is a raceme in which the single flowers are replaced by other simple racemes; the same structure can be repeated to form triple or more complex structures. Compound raceme inflorescences can either end with a final raceme ( homoeothetic ), or not ( heterothetic ). A compound raceme

2760-694: The modern phylogenomic data, the Phytelephantoideae are tribe in the Ceroxyloideae subfamily. Currently, few extensive phylogenetic studies of the Arecaceae exist. In 1997, Baker et al. explored subfamily and tribe relationships using chloroplast DNA from 60 genera from all subfamilies and tribes. The results strongly showed the Calamoideae are monophyletic, and Ceroxyloideae and Coryphoideae are paraphyletic. The relationships of Arecoideae are uncertain, but they are possibly related to

2820-660: The modern, specialized genera of palms appeared and became widespread and common, much more widespread than their range today. Because palms separated from the monocots earlier than other families, they developed more intrafamilial specialization and diversity. By tracing back these diverse characteristics of palms to the basic structures of monocots, palms may be valuable in studying monocot evolution. Several species of palms have been identified from flowers preserved in amber, including Palaeoraphe dominicana and Roystonea palaea . Fossil evidence of them can also be found in samples of petrified palmwood . The relationship between

2880-592: The most important characteristics are the intersection of the axes and different variations of the model. They may contain many flowers ( pluriflor ) or a few ( pauciflor ). Inflorescences can be simple or compound . Indeterminate simple inflorescences are generally called racemose / ˈ r æ s ɪ m oʊ s / . The main kind of racemose inflorescence is the raceme ( / ˈ r æ s iː m / , from classical Latin racemus , cluster of grapes ). The other kind of racemose inflorescences can all be derived from this one by dilation, compression, swelling or reduction of

2940-406: The plant's flowers are formed. On a larger scale, inflorescence architecture affects quality and quantity of offspring from selfing and outcrossing, as the architecture can influence pollination success. For example, Asclepias inflorescences have been shown to have an upper size limit, shaped by self-pollination levels due to crosses between inflorescences on the same plant or between flowers on

3000-544: The plants and the animals. These are crowned (graphically) with the Palms and with Man. Today, the palm, especially the coconut palm, remains a symbol of the tropical island paradise . Palms appear on the flags and seals of several places where they are native, including those of Haiti , Guam , Saudi Arabia , Florida , and South Carolina . Some species commonly called palms, though they are not true palms, include: Inflorescence Morphologically , an inflorescence

3060-399: The same kind of vascular cambium found in non-monocot woody plants . This explains the cylindrical shape of the trunk (almost constant diameter) that is often seen in palms, unlike in ring -forming trees. However, many palms, like some other monocots, do have secondary growth, although because it does not arise from a single vascular cambium producing xylem inwards and phloem outwards, it

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3120-486: The second largest). Raffia palms ( Raphia spp.) have the largest leaves of any plant, up to 25 metres (82 ft) long and 3 metres (10 ft) wide. The Corypha species have the largest inflorescence of any plant, up to 7.5 metres (25 ft) tall and containing millions of small flowers. Calamus stems can reach 200 metres (656 ft) in length. Most palms are native to tropical and subtropical climates. Palms thrive in moist and hot climates but can be found in

3180-403: The single flowers are replaced by cymes is called a (indefinite) thyrse . The secondary cymes can be of any of the different types of dichasia and monochasia. A botryoid in which the single flowers are replaced by cymes is a definite thyrse or thyrsoid . Thyrses are often confusingly called panicles . Other combinations are possible. For example, heads or umbels may be arranged in a corymb or

3240-485: The status of palms in the wild, use of wild palms, and palms under cultivation. Two projects on palm conservation and use supported by the World Wildlife Fund took place from 1985 to 1990 and 1986–1991, in the American tropics and southeast Asia, respectively. Both studies produced copious new data and publications on palms. Preparation of a global action plan for palm conservation began in 1991, supported by

3300-411: The stem. The leaves have a tubular sheath at the base that usually splits open on one side at maturity. The inflorescence is a spadix or spike surrounded by one or more bracts or spathes that become woody at maturity. The flowers are generally small and white, radially symmetric, and can be either uni- or bisexual. The sepals and petals usually number three each and may be distinct or joined at

3360-482: The subfamilies is shown in the following cladogram: Calamoideae Nypoideae Coryphoideae Ceroxyloideae Arecoideae Evidence for cultivation of the date palm by Mesopotamians and other Middle Eastern peoples exists from more than 5,000 years ago, in the form of date wood, pits for storing dates, and other remains of the date palm in Mesopotamian sites. The date palm had a significant effect on

3420-484: The top of an unbranched stem, except for the Hyphaene genus, who has branched palms. However, palms exhibit an enormous diversity in physical characteristics and inhabit nearly every type of habitat within their range, from rainforests to deserts . Palms are among the best known and most extensively cultivated plant families. They have been important to humans throughout much of history, especially in regions like

3480-647: The tropics, mostly in humid lowland subtropical climates, in highlands in southern Asia, and along the rim lands of the Mediterranean Sea . The northernmost native palm is Chamaerops humilis , which reaches 44°N latitude along the coast of Liguria , Italy . In the southern hemisphere, the southernmost palm is the Rhopalostylis sapida , which reaches 44°S on the Chatham Islands where an oceanic climate prevails. Cultivation of palms

3540-406: The vegetative to reproductive phase of a flower involves the development of an inflorescence meristem that generates floral meristems. Plant inflorescence architecture depends on which meristems becomes flowers and which become shoots. Consequently, genes that regulate floral meristem identity play major roles in determining inflorescence architecture because their expression domain will direct where

3600-426: The world. Along with dates mentioned above, members of the palm family with human uses are numerous: Like many other plants, palms have been threatened by human intervention and exploitation . The greatest risk to palms is destruction of habitat , especially in the tropical forests , due to urbanization , wood-chipping , mining , and conversion to farmland . Palms rarely reproduce after such great changes in

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