Luehea

Luehea divaricata

Luehea is a plant genus in the subfamily Grewioideae within the mallow ( Malvaceae ). It occurs with 15-20 species of trees and shrubs in the tropics and sub-tropics of Central and South America.

  • 6.1 Notes and references

Description

Vegetative characteristics

The Luehea species are trees or large shrubs. The stem base has in some species buttress roots. The change-constant leaves are short-stalked. The paired stipules fall off early. The simple, undivided leaf blades are elliptic, oblong- ovate or oblong - verkehrteiförmig and at the edge usually perforated or sawed. They have 3-8 pairs of lateral nerves, of which the basal pair is particularly well developed. The young branches, petioles and Spreitenunterseiten are more or less densely covered with stellate hairs.

Inflorescences

The stalked flowers grow singly or in few-flowered zymösen to reichblütigen thyrsischen to paniculate inflorescences. These are arranged in terminal or leaf axils. The bracts in the inflorescence are obsolete.

Flowers

The radial symmetry, fivefold, hermaphroditic flowers vary in size depending on the type. With particularly large blossoms Luehea candida is characterized by up to 55 mm long petals, relatively small flowers for example, has Luehea seemannii with 6.5-11 (-13 ) mm long petals. The flowers have an outer cup from 6-19 oblong to linealischen bracts. These are free or of different lengths connected to each other, but do not stay permanently deformed. They are obsolete or remain longer. The five oblong to lanceolate, klappigen in the bud sepals are free or at the base grow together briefly. They fall off after flowering. The five free, white, yellow or pink colored petals are longer than the calyx. They cover each other dachziegelig in the bud and are thickened at the base to a large, fleshy, differently shaped nectar gland. The numerous stamens are united at the base to a short five or ten bundles. Rarely these bundles are connected to a short stamen tube. The outer stamens are usually reduced to filamentous staminodes without anthers. These staminodes sometimes - such as Luehea conwentzii - also are missing or they are fused such as in Luehea grandiflora to kronblattartigen structures. The stamens are fluffy at the base to white villous or woolly hair. The anthers are movable at her back ( dorsifix ) attached to the filament. They are straight and intrors, so turned in the bud with their pollen sacs to flower towards the center, but rotate the blossoming outward and are horseshoe shaped. The two parallel along their entire length intergrown with each other counters open out through slots of length. The Upper permanent, sedentary or rarely very shortly stalked, fünffächerige ovary contains in each box at the central angle constant placenta numerous ovules. The simple style is thick, widened towards the tip slightly and has a kopfige, disc-shaped or lobed stigma.

Fruit and seeds

The woody, cylindrical or ellipsoidal capsule fruits open from the tip incomplete at most ¾ of their length fachspaltig in five flaps. The numerous small seeds have a crusty shell and seeds are widened at the top of a grand piano. They contain a fleshy endosperm. The embryo is straight and has flat, leaf -shaped cotyledons.

Chromosomes

Both previously studied species agree in their chromosome numbers coincide with each other. Both Luehea candicans and Luehea ochrophylla have a diploid set of chromosomes with 2n = 36

Dissemination

The distribution of the genus Luehea ranges from Mexico to northern Argentina.

Taxonomy

The genus was described in 1801 by Luehea Carl Ludwig Willdenow in the form of the name Lühea. The first description speciosa comprised only the type species Luehea. One older homonym is Luehea FWSchmidt, a name from 1793, which ericoides with the type species Luehea (L.) FWSchmidt ( = Stilbe ericoides (L.) L.) refers to the South African genus Stilbe. In order not to let the priority rule be applied, had the name Luehea Willd. therefore be protected as a noun conservandum. Alegria Moc. & Sessé ex DC. and Brotera Vell. are synonyms.

Etymology

The genus is named after Carl Emil Luehea of the Liihe (1751-1801), one originating from Holstein kk real eunuch, Lower Austrian Government and the former Danish chamberlain.

Species

The list includes 18 species. It is based on a compilation of currently accepted in regional species lists and floras species and may be incomplete.

Swell

  • Bayer, C.; Kubitzki, K. 2003: Malvaceae. In: K. Kubitzki (ed.): The families and genera of Vascular Plants. Volume V. Flowering Plants: Dicotyledons: Malvales, Capparales and Non- betalain Caryophyllales. Springer, Berlin, Heidelberg, New York. ISBN 3-540-42873-9. Pp. 225-311. - Preview at Google Book Search
  • Macbride, J. F. 1956: Tiliaceae. Linden Family. In: Flora of Peru. Field Mus. Nat. Hist. , Bot Ser. 13 (3A / 2): 413-442. - Luehea - Online.
  • Meijer, W. 2001: Tiliaceae Juss. In: Stevens, W. D.; Ulloa Ulloa C.; Pool, A.; Montiel, O. M. (ed.): Flora de Nicaragua. Monogr. Syst. Bot Missouri Bot Gard. ISBN 0-915279-95-9 85. - Luehea - Online
  • Robyns, A. 1964: 114 Family Tiliaceae. In: Woodson, RE & Schery, RW (eds.): Flora of Panama. Part VI. Ann. Missouri Bot Gard. 51: 1-35. - Luehea - Online
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