Cartilage

The title of this article is ambiguous. For the cartilaginous species of the genus Polycnemum from the foxtail family (Amaranthaceae) see cartilaginous herbs .

Cartilage
Cartilage herb ( Illecebrum verticillatum ), illustration
Systematics
Nuclear eudicotyledons Order : Clove-like (Caryophyllales) Family : Carnation family (Caryophyllaceae) Subfamily : Paronychioideae Genre : Cartilage Type : Cartilage
Scientific name of the  genus
Illecebrum
L.
Scientific name of the  species
Illecebrum verticillatum
L.

The cartilage herb ( Illecebrum verticillatum ), also called whorled cartilage chickweed , is the only species of the monotypical plant genus Illecebrum within the carnation family (Caryophyllaceae). It is common in Europe , Macaronesia and North Africa.

description

Habit and flowers of the whorled chickweed in the Südheide nature park

Vegetative characteristics

Cartilage is an annual herbaceous plant . All parts of the plant are bare. The prostrate, simple or slender stems branched at the base are usually 5 to 30 (to 70) centimeters long, square and mostly reddish.

The slightly fleshy, small leaves arranged opposite on the stem are sessile. The simple, bald and entire leaf blade is ovate to obovate with a length of 2 to 5 millimeters with a blunt upper end. The stipules are small and dry-skinned.

Generative characteristics

The flowering period extends from July to September. Four to six flowers are arranged in axillary tangles ( coils ). Per node ( wound dry ), there are two winding together a Scheinquirl form. Under each flower are two very small, white-skinned and 1 millimeter long prophylls .

The hermaphroditic and sessile flowers are radial symmetry and five-fold with (double) flower envelope . The five very small and free, white-greenish and hood-shaped, flabby, spongy sepals are 1.5 to 2.5 millimeters long, upright and incline together. At the tip of each sepal sits an awn 0.5 to 0.7 millimeters long . There are strongly reduced petals or they are missing, whereby these are also interpreted as staminodes. There are 3–5 very short stamens . The Upper constant ovary is unilocular with a basal ovule . The stylus is very short and has two scars .

The single, single-seeded, flappable, groovy opening capsule fruit in the constant calyx is grooved. The seeds are brown and shiny.

The number of chromosomes is 2n = 10.

ecology

There is self-pollination .

Habitus

Occurrence and endangerment

The distribution area of the cartilaginous herb is in Europe , Macaronesia and the Maghreb states. There are sites on Madeira and Tenerife , in Algeria , Morocco and Tunisia , in Denmark , in southern England , in the Netherlands , in Belgium , Germany , Austria , Poland , the Czech Republic , Slovakia , France (including Corsica), Portugal , Spain , Italy (including Sardinia) and Greece .

The cartilaginous herb thrives on sandy fields and damp locations: nutrient-rich, low-lime, acidic and loamy sand soils . It is thermophilic and only occurs in oceanic areas. In Central Europe it is a character species of the Spergulario-Illecebretum from the Nanocyperion association.

Cartilage is considered endangered in Germany, in Austria it is threatened with extinction and only occurs in the Lower Austrian Waldviertel .

Systematics

The genus Illecebrum was established in 1753 with the type species Illecebrum verticillatum by Carl von Linné in Species Plantarum , 1, p. 206. A homonym is Illecebrum Spreng. (in Kurt Sprengel : Instructions for Knowledge of the Plant , 2 (1), 1817, p. 317).

Illecebrum verticillatum is the only species of the genus Illecebrum from the tribe Paronychieae in the subfamily Paronychioideae within the family Caryophyllaceae .

literature

• Illecebrum verticillatum L., whorled chickweed. In: FloraWeb.de.
• Siegmund Seybold (Ed.): Schmeil-Fitschen interactive. (CD-Rom), Quelle & Meyer, Wiebelsheim 2001/2002, ISBN 3-494-01327-6 .
• Johann Christoph Röhling, Franz Carl Mertens & Wilhelm Daniel Joseph Koch : Germany's flora. Volume 2, Wilmans, 1826. limited preview in Google book search.
• William Baxter (Ed.): British Phænogamous Botany. Vol. VI, 1843, p. 471 f.
• CE Moss: The Cambrigde British Flora. Volume III, Cambridge Univ. Press, 1920, p. 12.

Web links

Commons : Chickweed ( Illecebrum verticillatum )  - Collection of images, videos and audio files

• Profile and distribution map for Bavaria . In: Botanical Information Hub of Bavaria .
• Distribution map on Den virtuellan Flora .
• Thomas Meyer: Data sheet with identification key and photos at Flora-de: Flora von Deutschland (old name of the website: Flowers in Swabia ) .

Individual evidence

1. ↑ ^{a b} Erich Oberdorfer : Plant-sociological excursion flora for Germany and neighboring areas . 8th edition. Verlag Eugen Ulmer, Stuttgart 2001, ISBN 3-8001-3131-5 . Page 389.
2. ^ ^{A b} Illecebrum in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved December 19, 2013.
3. ^ Illecebrum at Tropicos.org. Missouri Botanical Garden, St. Louis