Heterostachys

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Heterostachys
Heterostachys olivascens, illustration

Heterostachys olivascens , illustration

Systematics
Nuclear eudicotyledons
Order : Clove-like (Caryophyllales)
Family : Foxtail family (Amaranthaceae)
Subfamily : Salicornioideae
Tribe : Salicornieae
Genre : Heterostachys
Scientific name
Heterostachys
Ung.-Sternb.

Heterostachys is a genus of plants in the foxtail family(Amaranthaceae). They are shrubby salt plants with undivided stem axes and greatly reduced leaves and flowers. They occur in Central and South America.

description

Vegetative characteristics

The Heterostachys species are semi-shrubs or small shrubs . The branched stems are bare and not articulated. The leaves are alternate, they are fleshy, glabrous, scale-shaped, encompassing the stem, their free leaf blade is only one to two millimeters long.

Inflorescences and flowers

The spherical to cone-shaped inflorescences consist of alternate to almost opposite scale-shaped bracts , each with a single, free flower in the axilla. The hermaphrodite flowers have four half-grown, unevenly large tepals , two stamens and an ovary with two stigmas .

Fruits and seeds

At the time of fruiting, the flower cover becomes thick and spongy. The pericarp is membranous. The seed is lenticular to wedge-shaped and has a bumpy surface. The embryo is semicircular and there is abundant nutrient tissue.

Distribution and location

The types of Heterostachys are common in Central and South America . As salt plants , they colonize coastal lagoons and salty areas inland.

Systematics

The genus Heterostachys was established by Franz Ungern-Sternberg in 1876 . With this he replaced the invalid name Spirostachys Ung.-Sternb , which he described in 1866 . (This is illegitimate because Spirostachy's probe already existed). The type species is Heterostachys ritteriana .

The genus includes two types:

Heterostachys is closely related to Allenrolfea , which is also common in America. Their common lineage developed very early (in the Early to Middle Oligocene ), in the same period as the early Eurasian lineages of the Salicornieae . Presumably they reached America long before any other American representative of the Salicornieae.

Individual evidence

  1. ↑ a b c d e f Gudrun Kadereit, Ladislav Mucina & Helmut Freitag: Phylogeny of Salicornioideae (Chenopodiaceae): diversification, biogeography, and evolutionary trends in leaf and flower morphology , In: Taxon , Volume 55 (3), 2006, pages 623 , 624, 632.
  2. ^ Franz Ungern-Sternberg: Salicorniearum Synopsis . In: Atti del congresso internazionale botanico tenuto in Firenze nel mese di maggio 1874 , 1876, p. 331. First description of Heterostachys
  3. ↑ Franz Ungern-Sternberg: Attempt at a systematics of salicornies , Inaug. Diss., Dorpat: Karow., 1866, p. 100. First description of Spirostachys Ung.-Sternb. .
  4. ^ Heterostachys at Tropicos.org. Missouri Botanical Garden, St. Louis, accessed August 1, 2016.
  5. ^ FO Zuloaga, O. Morrone, MJ Belgrano, C. Marticorena, E. Marchesi. (Ed.) 2008. Catálogo de las plantas vasculares del Cono Sur. Monogr. Syst. Bot. Missouri Bot. Gard. 107 (1-3): i-xcvi, 1-3348. Heterostachys olivascens .
  6. ^ FO Zuloaga, O. Morrone, MJ Belgrano, C. Marticorena, E. Marchesi. (Ed.) 2008. Catálogo de las plantas vasculares del Cono Sur. Monogr. Syst. Bot. Missouri Bot. Gard. 107 (1-3): i-xcvi, 1-3348. Heterostachys ritteriana .

Web links

Commons : Heterostachys  - collection of images, videos and audio files
 Wikispecies: Heterostachys  - Species Directory