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63-680: See text Aulax is a South African Proteaceae genus of just three species of evergreen shrubs commonly known as "featherbushes". It is unusual among the many South African Proteaceae in having male and female flowers on separate plants. The bushes have fine needle-like foliage. In spring and summer female plants produce funnel-shaped Leucospermum -like flowerheads that develop into seed cones. The catkin-like male flowers are yellow. Described species are listed below: In all respects except frost hardiness, these are tough plants. They tolerate extreme heat , very low humidity, and prolonged drought. Like virtually all Proteaceae plants, they grow best on

126-468: A style and an apical structure called a stigma that receives pollen. The word "pistil" comes from Latin pistillum meaning pestle . A sterile pistil in a male flower is referred to as a pistillode . The pistils of a flower are considered to be composed of one or more carpels . A carpel is the female reproductive part of the flower—usually composed of the style , and stigma (sometimes having its individual ovary , and sometimes connecting to

189-551: A Southern Hemisphere family, with its main centres of diversity in Australia and South Africa. It also occurs in Central Africa, South and Central America , India , eastern and south eastern Asia , and Oceania . Only two species are known from New Zealand, although fossil pollen evidence suggests there were more previously. It is a good example of a Gondwanan family, with taxa occurring on virtually every land mass considered

252-409: A broad stigmatic crest along the margin allows pollen tubes access along the surface and between hairs at the margins. Two kinds of fusion have been distinguished: postgenital fusion that can be observed during the development of flowers, and congenital fusion that cannot be observed i.e., fusions that occurred during phylogeny. But it is very difficult to distinguish fusion and non-fusion processes in

315-428: A carpel or in groups of fused carpels. After fertilization, the gynoecium develops into a fruit that provides protection and nutrition for the developing seeds, and often aids in their dispersal. The gynoecium has several specialized tissues. The tissues of the gynoecium develop from genetic and hormonal interactions along three-major axes. These tissue arise from meristems that produce cells that differentiate into

378-552: A combination of brachy-paracytic stomata and the unusual trichome bases or, in other cases, the unusual structure of pollen tetrads. Xylocaryon was identified as a member of the Proteaceae from the similarity of its fruit to the extant genus Eidothea . Fossils attributable to this family have been found on the majority of areas that formed the Gondwana supercontinent. A wide variety of pollen belonging to this family dating back to

441-400: A conical or dome-shaped receptacle . In later lineages, carpels tend to be in whorls . The relationship of the other flower parts to the gynoecium can be an important systematic and taxonomic character. In some flowers, the stamens, petals, and sepals are often said to be "fused" into a "floral tube" or hypanthium . However, as Leins & Erbar (2010) pointed out, "the classical view that

504-472: A gametophyte shoot in mosses , liverworts , and hornworts . The corresponding terms for the male parts of those plants are clusters of antheridia within the androecium. Flowers that bear a gynoecium but no stamens are called pistillate or carpellate . Flowers lacking a gynoecium are called staminate. The gynoecium is often referred to as female because it gives rise to female (egg-producing) gametophytes; however, strictly speaking sporophytes do not have

567-497: A greater biodiversity for Proteaceae than currently exists, which supports the fact that the distribution of many taxa has changed drastically with the passage of time and that the family has suffered a general decline, including high levels of extinction during the Cenozoic . First described by French botanist Antoine Laurent de Jussieu , the family Proteaceae is a fairly large one, with around 80 genera, but less than 2,000 species. It

630-421: A hypanthium is present, but is either free from the gynoecium (in which case it may appear to be a cup or tube surrounding the gynoecium) or connected partly to the gynoecium (with the stamens, petals, and sepals attached to the hypanthium part of the way up the ovary). Perigynous flowers are often referred to as having a half-inferior ovary (or, sometimes, partially inferior or half-superior ). This arrangement

693-472: A light gritty soil with good drainage. They propagate from seed or half-hardened late summer-autumn cuttings. Proteaceae About 80, see text The Proteaceae / ˌ p r oʊ t i ˈ eɪ s iː / form a family of flowering plants predominantly distributed in the Southern Hemisphere . The family comprises 83 genera with about 1,660 known species . Australia and South Africa have

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756-666: A remnant of the ancient supercontinent Gondwana, except Antarctica . The family and subfamilies are thought to have diversified well before the fragmentation of Gondwana, implying all of them are well over 90 million years old. Evidence for this includes an abundance of proteaceous pollen found in the Cretaceous coal deposits of the South Island of New Zealand . It is thought to have achieved its present distribution largely by continental drift rather than dispersal across ocean gaps. No conclusive studies have been carried out on

819-412: A sex, only gametophytes do. Gynoecium development and arrangement is important in systematic research and identification of angiosperms , but can be the most challenging of the floral parts to interpret. Unlike (most) animals , plants grow new organs after embryogenesis , including new roots, leaves, and flowers. In the flowering plants, the gynoecium develops in the central region of the flower as

882-443: A shared basal ovary) —and usually interpreted as modified leaves that bear structures called ovules , inside which egg cells ultimately form. A pistil may consist of one carpel (with its ovary, style and stigma); or it may comprise several carpels joined together to form a single ovary, the whole unit called a pistil. The gynoecium may present as one or more uni-carpellate pistils or as one multi-carpellate pistil. (The number of carpels

945-460: A similar function to a megasporophyll , but typically includes a stigma, and is fused, with ovules enclosed in the enlarged lower portion, the ovary. In some basal angiosperm lineages, Degeneriaceae and Winteraceae , a carpel begins as a shallow cup where the ovules develop with laminar placentation, on the upper surface of the carpel. The carpel eventually forms a folded, leaf-like structure, not fully sealed at its margins. No style exists, but

1008-577: A smaller scale. The name Proteaceae was adapted by Robert Brown from the name Proteae coined in 1789 for the family by Antoine Laurent de Jussieu , based on the genus Protea , which in 1767, Carl Linnaeus derived from the name of the Greek god Proteus , a deity who was able to change between many forms. This is an appropriate image, seeing as the family is known for its astonishing variety and diversity of flowers and leaves. The genera of Proteaceae are highly varied, with Banksia in particular providing

1071-452: A source of dyes, firewood and as wood for construction. Aboriginal Australians eat the fruit of Persoonia , and the seeds of species from other genera, including Gevuina and Macadamia , form part of the diet of the indigenous peoples but are also sold throughout the world. The tender shoots of Helicia species are used in Java, and the nectar from the inflorescences of a number of species

1134-400: A stalked, integumented megasporangium (also called the nucellus ). Typically, one cell in the megasporangium undergoes meiosis resulting in one to four megaspores. These develop into a megagametophyte (often called the embryo sac) within the ovule. The megagametophyte typically develops a small number of cells, including two special cells, an egg cell and a binucleate central cell, which are

1197-682: A striking example of adaptive radiation in plants. This variability makes it impossible to provide a simple, diagnostic identification key for the family, although individual genera may be easily identified. Plant stems with two types of radii, wide and multi-serrated or narrow and uni-serrated, phloem stratified or not, trilacunar nodes with three leaf traces (rarely unilacunar with one trace), sclereids frequent; bark with lenticels frequently horizontally enlarged, cork cambium present, usually superficial. Roots lateral and short, often grouped in bundles ( proteoid roots ) with very dense root hairs, rarely with mycorrhiza . Generally speaking,

1260-528: A syncarpous gynoecium has a single style and stigma and a single locule in the ovary, it may be necessary to examine how the ovules are attached. Each carpel will usually have a distinct line of placentation where the ovules are attached. Pistils begin as small primordia on a floral apical meristem, forming later than, and closer to the (floral) apex than sepal, petal and stamen primordia. Morphological and molecular studies of pistil ontogeny reveal that carpels are most likely homologous to leaves. A carpel has

1323-425: A syncarpous gynoecium, the "fused" ovaries of the constituent carpels may be referred to collectively as a single compound ovary. It can be a challenge to determine how many carpels fused to form a syncarpous gynoecium. If the styles and stigmas are distinct, they can usually be counted to determine the number of carpels. Within the compound ovary, the carpels may have distinct locules divided by walls called septa . If

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1386-792: A thick rootstock buried in the ground that shoots up new stems after a fire, and others are reseeders , meaning the adult plants are killed by the fire, but disperse their seeds, which are stimulated by the smoke to take root and grow. The heat was previously thought to have stimulated growth, but the chemicals in the smoke have now been shown to cause it. There are four dioecious genera ( Aulax , Dilobeia , Heliciopsis and Leucadendron ), 11 andromonoecious genera and some other genera have species that are cryptically andromonoecious: two species are sterile and only reproduce vegetatively ( Lomatia tasmanica , Hakea pulvinifera ). The species vary between being autocompatible and autoincompatible, with intermediate situations; these situations sometimes occur in

1449-423: A unitary intercalary meristem. Evolutionary developmental biology investigates such developmental processes that arise or change during evolution. If the hypanthium is absent, the flower is hypogynous , and the stamens, petals, and sepals are all attached to the receptacle below the gynoecium. Hypogynous flowers are often referred to as having a superior ovary . This is the typical arrangement in most flowers. If

1512-536: Is apocarpous . If a gynoecium has multiple carpels "fused" into a single structure, it is syncarpous . A syncarpous gynoecium can sometimes appear very much like a monocarpous gynoecium. The degree of connation ("fusion") in a syncarpous gynoecium can vary. The carpels may be "fused" only at their bases, but retain separate styles and stigmas. The carpels may be "fused" entirely, except for retaining separate stigmas. Sometimes (e.g., Apocynaceae ) carpels are fused by their styles or stigmas but possess distinct ovaries. In

1575-678: Is also cultivated for its edible nuts, in Chile and New Zealand , and they are also used in the pharmaceutical industry for their humectant properties and as an ingredient in sunscreens . It is the most cold-resistant of the tree families that produce nuts. It is also planted in the British Isles and on the Pacific coast of the United States for its tropical appearance and its ability to grow in cooler climates . Many Proteaceae species are cultivated by

1638-546: Is called the funiculus. Stigmas can vary from long and slender to globe-shaped to feathery. The stigma is the receptive tip of the carpel(s), which receives pollen at pollination and on which the pollen grain germinates . The stigma is adapted to catch and trap pollen, either by combining pollen of visiting insects or by various hairs, flaps, or sculpturings. The style and stigma of the flower are involved in most types of self incompatibility reactions. Self-incompatibility, if present, prevents fertilization by pollen from

1701-617: Is carried out by bees , beetles , flies , moths , birds ( honeyeaters , sunbirds , sugarbirds and hummingbirds ) and mammals (rodents, small marsupials , elephant shrews and bats ). The latter two means were evolutionarily derived from entomophily in different, independent events. The dispersion of some species exhibit serotiny , which is associated with their pyrophytic behaviour. These trees accumulate fruits on their branches whose outer layers or protective structures ( bracts ) are highly lignified and resistant to fire. The fruit only release their seeds when they have been burnt and when

1764-448: Is denoted by terms such as tricarpellate (three carpels).) Carpels are thought to be phylogenetically derived from ovule-bearing leaves or leaf homologues ( megasporophylls ), which evolved to form a closed structure containing the ovules. This structure is typically rolled and fused along the margin. Although many flowers satisfy the above definition of a carpel, there are also flowers that do not have carpels because in these flowers

1827-452: Is drunk in Australia. Traditional medicines can be obtained from infusions of the roots, bark, leaves, or flowers of many species that are used as topical applications for skin conditions or internally as tonics, aphrodisiacs, and galactogens to treat headaches, cough, dysentery, diarrhea, indigestion, stomach ulcers, and kidney disease. The wood from the trees of this family is widely used in construction and for internal uses such as decoration;

1890-432: Is highly specialised. It usually involves the use of a "pollen-presenter", an area on the style -end that presents the pollen to the pollinator. Proteaceae flower parts occur in fours. The four tepals are fused into a long, narrow tube with a closed cup at the top, and the filaments of the four stamens are fused to the tepals in such a way that the anthers are enclosed within the cup. The pistil initially passes along

1953-517: Is particularly frequent in the rose family and saxifrages . Occasionally, the gynoecium is born on a stalk, called the gynophore , as in Isomeris arborea . Within the ovary, each ovule is born by a placenta or arises as a continuation of the floral apex. The placentas often occur in distinct lines called lines of placentation . In monocarpous or apocarpous gynoecia, there is typically a single line of placentation in each ovary. In syncarpous gynoecia,

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2016-463: Is recognised by virtually all taxonomists . Firmly established under classical Linnaean taxonomy , it is also recognised by the cladistics -based APG and APG II systems. It is placed in the order Proteales , whose placement has itself varied. A classification of the genera within Proteaceae was made by Lawrie Johnson and Barbara Briggs in their influential 1975 monograph " On the Proteaceae:

2079-525: Is thought to be extinct. The species of this family are particularly susceptible to the destruction or fragmentation of their habitat , fire, parasitic diseases, competition from introduced plants, soil degradation and other damage provoked by humans and their domesticated animals. The species are also affected by climate change . The Proteaceae have a rich fossil record, despite the inherent difficulties in identifying remains that do not show diagnostic characteristics. Identification usually comes from using

2142-444: Is valued for its vivid yellow flowers and grape-like fruit. Adenanthos sericeus (woolly bush) is planted for its attractive soft leaves and its small red or orange flowers. Hicksbeachia pinnatifolia (beef nut, red bauple nut) is commonly planted for its foliage and edible nuts. The Proteaceae are particularly susceptible to certain parasites, in particular the oomycete Phytophthora cinnamomi , which causes severe root rot in

2205-455: The Faroe Islands at a latitude of 62° north. Among the banksias , many of which grow in temperate and Mediterranean climates, the vast majority are shrubs; only a few are trees that are valued for their height. Among the tallest species are: B. integrifolia with its subspecies B. integrifolia subsp. monticola , which is noteworthy as the plants that form the subspecies are

2268-409: The gametes involved in double fertilization . The central cell, once fertilized by a sperm cell from the pollen becomes the first cell of the endosperm , and the egg cell once fertilized become the zygote that develops into the embryo . The gap in the integuments through which the pollen tube enters to deliver sperm to the egg is called the micropyle . The stalk attaching the ovule to the placenta

2331-417: The nursery industry as barrier plants and for their prominent and distinctive flowers and foliage. Some species are of importance to the cut flower industry , especially some Banksia and Protea species. Sugarbushes ( Protea ), pincushions ( Leucospermum ) and conebushes ( Leucadendron ), as well as others like pagodas ( Mimetes ), Aulax and blushing brides ( Serruria ), comprise one of

2394-432: The Proteaceae are one of few flowering plant families that do not form symbioses with arbuscular mycorrhizal fungi. They exude large amounts of organic acids ( citric acid and malic acid ) every 2–3 days in order to aid the mobilization and absorption of phosphate. Many species are fire-adapted ( pyrophytes ), meaning they have strategies for surviving fires that sweep through their habitat. Some are resprouters , and have

2457-587: The Upper Cretaceous ( Campanian - Maastrichtian ) from the south east of Australia and pollen from the Middle Cretaceous ( Cenomanian - Turonian ) from northern Africa and Peru described as Triorites africaensis . The first macrofossils appear twenty million years later in the Palaeocene of South America and the north east of Australia. The fossil record of some areas, such as New Zealand and Tasmania, show

2520-821: The chemical substances present in this broad family. The genera Protea and Faurea are unusual as they use xylose as the main sugar in their nectar and as they have high concentrations of polygalactol, while sucrose is the main sugar present in Grevillea . Cyanogenic glycosides , derived from tyrosine , are often present, as are proanthocyanidines ( delphinidin and cyanidin ), flavonols ( kaempferol , quercetin and myricetin ) and arbutin . Alkaloids are usually absent. Iridoids and ellagic acid are also absent. Saponins and sapogenins can be either present or absent in different species. Many species accumulate aluminium . Many traditional cultures have used Proteaceae as sustenance, medicine, for curing animal hides, as

2583-415: The cup splits apart, and the pistil is released to spring more or less upright. Many of the Proteaceae have specialised proteoid roots , masses of lateral roots and hairs forming a radial absorptive surface, produced in the leaf litter layer during seasonal growth, and usually shrivelling at the end of the growth season. They are an adaptation to growth in poor, phosphorus-deficient soils, greatly increasing

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2646-413: The diagnostic feature of Proteaceae is the compound pseudanthium . In many genera, the most obvious feature is the large and often very showy inflorescences , consisting of many small flowers densely packed into a compact head or spike. This character does not occur in all Proteaceae, however; Adenanthos species, for example, have solitary flowers. In most Proteaceae species, the pollination mechanism

2709-469: The different tissues that produce the parts of the gynoecium including the pistil, carpels, ovary, and ovules; the carpel margin meristem (arising from the carpel primordium ) produces the ovules , ovary septum, and the transmitting track, and plays a role in fusing the apical margins of carpels. The gynoecium may consist of one or more separate pistils. A pistil typically consists of an expanded basal portion called an ovary , an elongated section called

2772-426: The evolution and classification of a southern family ", until it was largely superseded by the molecular studies of Peter H. Weston and Nigel Barker in 2006. Proteaceae are now divided into five subfamilies: Bellendenoideae , Persoonioideae , Symphionematoideae , Proteoideae and Grevilleoideae . In 2008 Mast and colleagues updated Macadamia and related genera in tribe Macadamieae. Furthermore, Orites megacarpus

2835-476: The evolution of flowering plants. Some processes that have been considered congenital (phylogenetic) fusions appear to be non-fusion processes such as, for example, the de novo formation of intercalary growth in a ring zone at or below the base of primordia. Therefore, "it is now increasingly acknowledged that the term 'fusion,' as applied to phylogeny (as in 'congenital fusion') is ill-advised." Basal angiosperm groups tend to have carpels arranged spirally around

2898-821: The greatest concentrations of diversity. Together with the Platanaceae (plane trees), Nelumbonaceae (the sacred lotus) and in the recent APG IV system the Sabiaceae , they make up the order Proteales . Well-known Proteaceae genera include Protea , Banksia , Embothrium , Grevillea , Hakea , and Macadamia . Species such as the New South Wales waratah ( Telopea speciosissima ), king protea ( Protea cynaroides ), and various species of Banksia , Grevillea , and Leucadendron are popular cut flowers . The nuts of Macadamia integrifolia are widely grown commercially and consumed, as are those of Gevuina avellana on

2961-504: The ground has been fertilized with ashes from the fire and is free from competitors. Many species have seeds with elaiosomes that are dispersed by ants ; the seeds with wings or thistledown exhibit anemochory , while the drupes and other fleshy fruit exhibit endozoochory as mammals and birds ingest them. Some African and Australian rodents are known to accumulate fruit and seeds of these plants in their nests in order to feed on them, although some manage to germinate. Proteaceae are mainly

3024-495: The hypanthium is present up to the base of the style(s), the flower is epigynous . In an epigynous flower, the stamens, petals, and sepals are attached to the hypanthium at the top of the ovary or, occasionally, the hypanthium may extend beyond the top of the ovary. Epigynous flowers are often referred to as having an inferior ovary . Plant families with epigynous flowers include orchids , asters , and evening primroses . Between these two extremes are perigynous flowers, in which

3087-417: The inside of the perianth tube, so the stigma, too, is enclosed within the cup. As the flower develops, the pistil grows rapidly. Since the stigma is trapped, the style must bend to elongate, and eventually it bends so far, the perianth is split along one seam. The style continues to grow until anthesis , when the nectaries begin to produce nectar . At this time, the perianth splits into its component tepals,

3150-436: The lines of placentation can be regularly spaced along the wall of the ovary ( parietal placentation ), or near the center of the ovary. In the latter case, separate terms are used depending on whether or not the ovary is divided into separate locules. If the ovary is divided, with the ovules born on a line of placentation at the inner angle of each locule, this is axile placentation . An ovary with free central placentation , on

3213-409: The nectar-feeders act as pollinators. The downside of this pollination strategy is that the probability of self-fertilisation is greatly increased; many Proteaceae counter this with strategies such as protandry , self-incompatibility, or preferential abortion of selfed seed. The systems for presenting pollen are usually highly diverse, corresponding to the diversification of the pollinators. Pollination

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3276-438: The other hand, consists of a single compartment without septae and the ovules are attached to a central column that arises directly from the floral apex (axis). In some cases a single ovule is attached to the bottom or top of the locule ( basal or apical placentation , respectively). In flowering plants, the ovule (from Latin ovulum meaning small egg) is a complex structure born inside ovaries. The ovule initially consists of

3339-444: The ovule(s), although enclosed, are borne directly on the floral apex. Therefore, the carpel has been redefined as an appendage that encloses ovule(s) and may or may not bear them. However, the most unobjectionable definition of the carpel is simply that of an appendage that encloses an ovule or ovules. If a gynoecium has a single carpel, it is called monocarpous . If a gynoecium has multiple, distinct (free, unfused) carpels, it

3402-617: The plants that grow in Mediterranean climates. Fusarium oxysporum causes a disease called fusariosis in roots that causes a yellowing and wilting, with serious ecological damages to woodland plants and economic losses in plants of commercial interest. Other common infections are caused by species of Botryosphaeria , Rhizoctonia , Armillaria , Botrytis , Calonectria and other fungi. The IUCN considers that 47 Proteaceae species are threatened, of which one species, Stenocarpus dumbeensis Guillaumin , 1935, from New Caledonia,

3465-542: The plants' access to scarce water and nutrients by exuding carboxylates that mobilise previously unavailable phosphorus. They also increase the root's absorption surface, but this is a minor feature, as it also increases competition for nutrients against its own root clusters. However, this adaptation leaves them highly vulnerable to dieback caused by the Phytophthora cinnamomi water mould , and generally intolerant of fertilization . Due to these specialized proteoid roots,

3528-425: The same species. The flowers are usually protandrous. Just before anthesis, the anthers release their pollen , depositing it onto the stigma, which in many cases has an enlarged fleshy area specifically for the deposition of its own pollen. Nectar-feeders are unlikely to come into contact with the anthers themselves, but can hardly avoid contacting the stigma; thus, the stigma functions as a pollen-presenter , ensuring

3591-448: The species of this genus, around 170 species, are shrubs, although some of them are valued for their flowers. Another species that is cultivated in some parts of the world, although it is smaller, is Telopea speciosissima (Waratah), from the mountains of New South Wales , Australia . Some temperate climate species are cultivated more locally in Australia for their attractive appearance: Persoonia pinifolia (pine-leaved geebung )

3654-439: The tallest trees of the banksias and they are more frost-resistant than other banksias, B. seminuda , B. littoralis , B. serrata ; among those that can be considered small trees or large shrubs: B. grandis , B. prionotes , B. marginata , B. coccinea and B. speciosa ; all of these are planted in parks and gardens and even along roadsides because of their size. The rest of

3717-782: The three main plant groups of fynbos , which forms part of the Cape Floral Kingdom , the smallest but richest plant kingdom for its size and the only kingdom contained within a single country. The other main groups of plants in fynbos are the Ericaceae and the Restionaceae . South African proteas are thus widely cultivated due to their many varied forms and unusual flowers. They are popular in South Africa for their beauty and their usefulness in wildlife gardens for attracting birds and useful insects. The species most valued as ornamentals are

3780-515: The trees that grow in southern latitudes as they give landscapes in temperate climates a tropical appearance; Lomatia ferruginea (Fuinque), Lomatia hirsuta (Radal) have been introduced in Western Europe and to the western United States . Embothrium coccineum (Chilean Firetree or Notro ) is highly valued in the British Isles for its dark red flowers and can be found as far north as

3843-407: The wall of the inferior ovary results from the "congenital" fusion of dorsal carpel flanks and the floral axis does not correspond to the ontogenetic processes that can actually be observed. All that can be seen is an intercalary growth in a broad circular zone that changes the shape of the floral axis (receptacle)." And what happened during evolution is not a phylogenetic fusion but the formation of

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3906-585: The wood from species of Protea , Leucadendron and Grevillea is especially popular. Many species are used in gardening, particularly genera of Banksia , Embothrium , Grevillea , and Telopea . This use has resulted in the introduction of exotic species that have become invasive; examples include the hakea willow ( Hakea salicifolia ) and the silky hakea ( Hakea sericea ) in Portugal. Two species of Macadamia are cultivated commercially for their edible nuts. Gevuina avellana (Chilean hazel)

3969-450: Was found not to be within the genus Orites , nor in the tribe Roupaleae, instead in the tribe Macadamieae, hence given the new species name Nothorites megacarpus . The full arrangement, according to Weston and Barker (2006) with the updates to genera from Mast et al. (2008), is as follows: Carpel The term gynoecium is also used by botanists to refer to a cluster of archegonia and any associated modified leaves or stems present on

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