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An order of flowering plants consisting of six families, the best known of which are Magnoliaceae (220 species) and Annonaceae (2200 species). The others contain some botanically interesting and peculiar plants (305 species), but none besides Myristicaceae (300 species) are commonly encountered. Previously, many authors have considered these families as among the most primitive of the flowering plants, but in all cases the plants exhibit some highly derived traits. Although their fruits are often cited as the most primitive in the flowering plants, their carpels are not fused but the edges are sealed, unlike those of Nymphaeaceae and Chloranthaceae, which are not sealed at maturity. Their “primitiveness” has been overemphasized; studies of sequences of deoxyribonucleic acid (DNA) demonstrate that Magnoliales are closely related to Laurales, Piperales, and Winterales, and then more distantly to the monocotyledons.
Industry:Science
An order of flowering plants in the core eudicots. The order consists of 10 families and approximately 9300 species. The circumscription of the order has been relatively stable, with only minor changes made on the basis of deoxyribonucleic acid (DNA) sequence data. The two largest families are Melastomataceae (approximately 4500 species) and Myrtaceae (approximately 3000 species). Thymelaeaceae are excluded in recent concepts of the order, being related instead to families of Malvales. Vochysiaceae, traditionally included in Polygalales, have been shown to be members of Myrtaceae with DNA sequence data.
Industry:Science
An order of flowering plants in the core eudicots. The order consists of 10 families and more than 5500 species. The circumscription of the order has been altered greatly in recent years, largely on the basis of deoxyribonucleic acid (DNA) sequence data. Of the five families in the traditional concept (Bombacaceae, Malvaceae, Sterculiaceae, Tiliaceae, and Elaeocarpaceae), the first four have been combined as Malvaceae, due to lack of monophyly of three of these families in their traditional circumscription; and Elaeocarpaceae are included in Oxalidales. In addition, other families have been transferred to Malvales, including Dipterocarpaceae and Thymelaeaceae. The expanded order is characterized by the presence of mucilage in epidermal cells and cavities; and of palmate leaves, stellate hairs, and numerous stamens with partially fused filaments occur frequently.
Industry:Science
An order of flowering plants in the eurosid I group of the rosid eudicots. In previous modern systems of classifications, this order was considered to be much larger and to contain up to 25 families, but recently on the basis of DNA sequence studies the number of families was greatly reduced and changed. The order as now recognized contains only 11 families, many of which are small. Many families in this order are wind-pollinated (the former Urticales, for example Moraceae, Ulmaceae, and Urticaceae) and exhibit the typical syndrome of small petalless flowers with dangling anthers, whereas the other families are insect-pollinated with large, showy flowers in which the carpels are sometimes free.
Industry:Science
An order of flowering plants in the eurosid I group of the rosid eudicots. This order comprises just two small families of distant relationship (as evidenced by DNA sequence studies) to all other rosid eudicots: Krameriaceae and Zygophyllaceae. In previous systems of classification, both families were placed in the highly unnatural order Polygalales or Sapindales, the families of which share with them only highly zygomorphic flowers. Krameriaceae (25 species) are photosynthetic parasitic plants (“hemiparasites”) found from the southwestern United States to South America, whereas Zygophyllaceae (240 species) are free-living and widely distributed in arid to semiarid zones throughout the warmer regions of the world. Some species of the latter family produce especially hard woods such as lignumvitate (<i>Bulnesia</i> and <i>Guaiacum</i>), and a few others produce medicinal compounds, such as the creosote bush (<i>Larrea</i>).
Industry:Science
An order of flowering plants near the base of the eudicots; DNA sequence analysis has indicated that this order includes few families that have been associated together in previous classifications. The order's exact relationships to other orders are still under study, but Saxifragales appear to be related to the rosid eudicots. They include 13 small to moderately sized families and perhaps around 2300 species. There are two categories: woody species that are sometimes wind-pollinated, and insect-pollinated herbs. The members are difficult to characterize morphologically but fall into several sets of families that have been considered closely related by most authors.
Industry:Science
An order of flowering plants that have previously been included in the same larger grouping as Magnoliales, the Magnoliidae. Deoxyribonucleic acid (DNA) sequence studies have demonstrated that Nymphaeales as previously defined contain two families, Ceratophyllaceae (water hornwort) and Nelumbonaceae (lotus), that are not closely related to the others. Remaining in the order is the family Nymphaeaceae, the waterlilies, from which a small group of tropical plants, Cabombaceae, are split by some scientists. Nymphaeaceae contain nearly 100 species of fresh-water aquatics that are typically found in river and lake systems throughout the world. The ovaries of these plants are filled with mucilage, which mediates pollen tube growth from the stigmas to the ovules, and they have either inappertuate or monosulcate pollen. A spectacular plant is the Amazonian water lily (<i>Victoria</i>), which has leaves up to 15 ft (5 m) in diameter. The water lily family has been shown by deoxyribonucleic acid analyses to be one of the oldest lineages of flowering plants and distantly related to all others as well. The family members are relics of the early diversification of the flowering plants.
Industry:Science
An order of flowering plants, division Magnoliophyta (Angiospermae) in the subclass Dilleniidae of the class Magnoliopsida (dicotyledons). The order consists of 5 families and about 1750 species, the Sapotaceae (about 800 species) and Ebenaceae (about 450 species) being the largest and most familiar families. The Ebenales are woody, chiefly tropical, sympetalous plants (those with flowers have the petals joined by their margins, at least toward the base, forming a basal tube, cup, or saucer) with usually twice as many stamens (including staminodes) as corolla lobes. When there is a single set of stamens, these are generally opposite the corolla lobes. Ordinarily there are only one or two ovules in each locule and the placentation is axile (that is, the placenta forms a central axis in an ovary which is divided by longitudinal partitions into two or more chambers). In a cross section of such an ovary, the partitions radiate from the central axis (placenta) to the lateral wall of the ovary. Chicle (from <i>Manilkara sapota</i>, in the Sapotaceae) and ebony (<i>Diospyros ebeneum</i>) are obtained from members of the Ebenales.
Industry:Science
An order of flowering plants, division Magnoliophyta (Angiospermae) in the subclass Hamamelidae of the class Magnoliopsida (dicotyledons). The order consists of a single family, genus, and species (<i>Leitneria floridana</i>) of the southeastern United States. The plants are simple-leaved, dioecious shrubs with the flowers in catkins. The ovary is superior and pseudomonomerous, with a single ovule ripening into a small drupe.
Industry:Science
An order of flowering plants, division Magnoliophyta (Angiospermae) in the subclass Zingiberidae of the class Liliopsida (monocotyledons). It consists of the single family Bromeliaceae, with about 45 genera and 2000 species, occurring chiefly in tropical and subtropical America. They are firm-leaved, terrestrial xerophytes (adapted structurally to live and grow with a limited water supply), or very often epiphytes (living on other plants nonparasitically), with six stamens and regular or somewhat irregular flowers that usually have septal nectaries and an inferior ovary. The order has often been associated with several related ones in a larger order, Farinosae, marked by its starchy endosperm. Spanish moss (<i>Tillandsia</i>) and the cultivated pineapple (<i>Ananas</i>) are familiar members of the Bromeliales, and many others attract attention as houseplants.
Industry:Science
