Leptoglossis

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Leptoglossis
Systematics
Nuclear eudicotyledons
Asterids
Euasterids I
Order : Nightshade (Solanales)
Family : Nightshade family (Solanaceae)
Genre : Leptoglossis
Scientific name
Leptoglossis
Benth.

Leptoglossis is a genus of plants fromthe nightshade family (Solanaceae). Seven species are assigned to the genus, which are distributed in two disjoint areas of South America.

description

Vegetative characteristics

Leptoglossis species are xerophytic (adapted to drought), annual or perennial plants, the height of which can be between 5 and 100 cm. It is typical of the genus that the bark of the stem axis does not contain any firming tissue ( collenchyma ) and that the endodermis forms a starchy sheath. Both the phloem and the pith are not fibrous, unlike the pericycle . The hair consists of different types of trichomes : Mostly there are glandular trichomes with single-cell, two- to four-cell or multicellular heads or non-glandular trichomes, branched trichomes are also rarely found.

The leaves are usually narrow and stem-like, sometimes linear with a size of 8 to 25 × 1 to 5 mm. They can have long petioles or be sessile. There are two types of leaf shape dimorphism, in which the lower leaves are broad and have long petioles and form a rosette on the ground, and the upper leaves are sessile and stem-like.

The base chromosome number of the two species examined so far is , whereby Leptoglossis linifolia is diploid ( ) and Leptoglossis schwenkioides is tetraploid ( ).

blossoms

The calyx is 4 to 6 mm long and usually five-fold and radially symmetrical . The exception is the species Leptoglossis albiflora , which has a zygomorphic , seven to ten-fold calyx. The venature of the sepals is also typical for the genus, with five longitudinal stripes between the main veins and no development of conductive tissue. The crown comes in different colors, for example smoky yellow, cream-colored, lavender or violet and is 9 to 19 cm long and bulbous. Another special feature of the genus is the degree of fusion of the stamens with the crown. With the exception of the Argentine species Leptoglossis linifolia , the species of the genus have relatively long stamens, the growth of which with the petals can reach up to half of the corolla tube. Leptoglossis linifolia, on the other hand, has shorter stamens that are fused with the petals on an enlarged crown base. Leptoglossis schwenkioides the only species of the genus has four fertile stamens, two of which are more anther than the other two, laterally situated dust bag. The other types of the genus have only two fertile stamens and form three reduced, sterile stamens. The anthers have a length of 1 to 1.6 mm, the outer shape is circular or slightly longer than wide. The counters are always grown together.

Fruits and seeds

The fruits are elongated, bowl-shaped and protrude from the calyx. They contain about 100 polyhedral seeds with a length of 0.3 to 0.5 mm. The seed coat (testa) is finely structured like a honeycomb, the endosperm is abundant.

distribution

The species of the genus occur in two disjoint areas of South America. Most of the species can be found in Peru , only one in Argentina .

Systematics

Here is a selection of the types:

ecology

Butterfly pollination is a common feature within the genus, which can be recognized by the very clearly mobile anthers.

Botanical history

The genus was first described in 1845 by George Bentham with the species Leptoglossis schwenkioides . Wettstein did not recognize this genus in 1891 in The Natural Plant Families and assigned it as a section to the Salpiglossis . The description of the genera Cyclostigma by Philippi in 1870 and Leptofeddea by Diels in 1919 later turned out to be synonymous with Leptoglossis . A part that was initially referred to as Leptoglossis subgenus Brachyglossis by Asa Gray in 1877 was described in 1976 by William D'Arcy as a separate genus Hunzikeria , in which three species are now distinguished.

literature

  • Armando T. Hunziker: The Genera of Solanaceae . ARG Gantner Verlag KG, Ruggell, Liechtenstein 2001. ISBN 3-904144-77-4 .