Small two-leaf

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Small two-leaf
Heartleaf Twayblade (3816689446) .jpg

Small two-leaf ( Listera cordata )

Systematics
Order : Asparagales (Asparagales)
Family : Orchids (orchidaceae)
Subfamily : Epidendroideae
Tribe : Neottieae
Genre : Two-leaf ( Listera )
Type : Small two-leaf
Scientific name
Listera cordata
( L. ) R.Br.

The small two-sheet ( Listera cordata ) even heart-two-blade called, is a species of the genus two-sheet ( Listera ) within the family of orchids (Orchidaceae).

description

Illustration from Atlas of Alpine Flora

The small two-leaf is a very delicate, perennial herbaceous plant and reaches heights of 7 to 20 centimeters. There are two opposite leaves on its stem . The simple, shiny leaf blade is triangular and heart-shaped with a length of 1 to 3 centimeters.

The flowering period extends from May to August. Six to ten flowers are grouped into a loose cluster . The outside greenish flowers have reddish inner tepals . The lip, which is also reddish, is deeply split in two with pointed tips, and there are two pointed teeth at the base of the lip . The flowers are wide open.

The number of chromosomes is 2n = 34, 36, 38, 40 or 42.

ecology

The small two-leaf is a rhizome geophyte . As a shade plant and saprophytic gullet, it makes high demands on the humidity .

The Small two sheet of insects , mostly two- and Hymenoptera pollinated . Self-pollination is rare. The seeds are spread over the wind . Subterranean runners ensure vegetative reproduction .

Occurrence

The small two-leaf is a circumpolar , Euro-Siberian-North American floral element . Its distribution area belongs to the northern foothills of a European Alpine area , which extends from the Pyrenees over the Alps, Carpathians , the Balkans , Bulgaria , northern Greece , northeast Turkey to the Caucasus region .

In Central Europe it populates mainly spruce and pine forests, and there it also goes to locations with overgrown peat moss . It also thrives in coniferous stands on the edge of raised bogs . It occurs only sporadically in Central Europe in the lowlands . Even in silicate low mountain ranges and on decalcified areas of the lime low mountain ranges and in corresponding areas of the Alps it is largely absent. It rises in the Alps to the tree line . In the Allgäu Alps in Bavaria, on the Gottesacker plateau near the former Gottesacker Alpe , it rises up to 1930 meters above sea level. According to Baumann and Künkele , the species has the following altitude limits in the Alpine countries: Germany 20–2000 meters, France 600–2300 meters, Switzerland 440–2100 meters, Liechtenstein 1490–1900 meters, Austria 500–1900 meters, Italy 900–2040 meters, Slovenia 680–1900 meters. In Europe it has the limits of 10–2300 meters, in the United States it rises to 3500 meters above sea level.

Even in locations where it seldom occurs, it can sometimes be found in small, relatively poor and moderately dense stands. The little two-leaf grows best on at least superficially acidic and lime-poor soils , which should be rich in raw humus and poor in nutrients . It grows in different plant communities of the class Vaccinio-Piceetea .

Danger

The small double leaf is considered safe throughout Central Europe. According to the Federal Species Protection Ordinance , it is particularly protected. In Germany it is in 3rd place on the red list .

literature

  • Henning Haeupler , Thomas Muer: picture atlas of the fern and flowering plants of Germany (= the fern and flowering plants of Germany. Volume 2). 2nd, corrected and enlarged edition. Published by the Federal Agency for Nature Conservation. Ulmer, Stuttgart 2007, ISBN 978-3-8001-4990-2 .
  • Ruprecht Düll , Herfried Kutzelnigg : Pocket dictionary of plants in Germany and neighboring countries. The most common Central European species in portrait. 7th, corrected and enlarged edition. Quelle & Meyer, Wiebelsheim 2011, ISBN 978-3-494-01424-1 .
  • Oskar Sebald, Siegmund Seybold , Georg Philippi, Arno Wörz (eds.): The fern and flowering plants of Baden-Württemberg. Volume 8: Special part (Spermatophyta, subclasses Commelinidae part 2, Arecidae, Liliidae part 2): Juncaceae to Orchidaceae. Eugen Ulmer, Stuttgart 1998, ISBN 3-8001-3359-8 .
  • Dietmar Aichele, Heinz-Werner Schwegler: The flowering plants of Central Europe . 2nd Edition. tape 5 : Swan flowers to duckweed plants . Franckh-Kosmos, Stuttgart 2000, ISBN 3-440-08048-X .
  • Eckehart J. Jäger (ed.): Excursion flora from Germany. Vascular plants: baseline. Founded by Werner Rothmaler . 20th, revised and expanded edition. Spektrum Akademischer Verlag, Heidelberg 2011, ISBN 978-3-8274-1606-3

Individual evidence

  1. ^ Erich Oberdorfer : Plant-sociological excursion flora for Germany and neighboring areas . 8th edition. Verlag Eugen Ulmer, Stuttgart 2001, ISBN 3-8001-3131-5 . Page 273.
  2. ↑ Erhard Dörr, Wolfgang Lippert : Flora of the Allgäu and its surroundings. Volume 1, IHW, Eching 2001, ISBN 3-930167-50-6 , p. 393.
  3. ↑ a b Helmut Baumann , Siegfried Künkele : Orchidaceae . In: Oskar Sebald u. a .: The fern and flowering plants of Baden-Württemberg . 1st edition Volume 8, page 328. Verlag Eugen Ulmer, Stuttgart 1998. ISBN 3-8001-3359-8

Web links

Commons : Small two-leaf ( Listera cordata )  - album with pictures, videos and audio files