Thalassia testudinum

Thalassia testudinum
Thalassia testudinum near San Salvador, Bahamas
Systematics
Monocots Order : Frog-spoon-like (Alismatales) Family : Frog bite family (Hydrocharitaceae) Subfamily : Hydrilloideae Genre : Thalassia Type : Thalassia testudinum
Scientific name
Thalassia testudinum
Banks ex KDKoenig

Thalassia testudinum is one of two species of plants in the genus Thalassia . It occurs in the Gulf of Mexico and the Caribbean.

description

The rhizomes are elongated and 3 to 6 millimeters in diameter. The leaves measure 10 to 60 × 0.4 to 1.2 centimeters. They have entire margins, the edge is sawn only towards the tip. There are 9 to 15 leaf veins. The male inflorescence is one to three-flowered. The inflorescence axis is 3 to 7 inches long. The edges of the spathe are fused on one side. The female inflorescence is single-flowered. The inflorescence axis is 3 to 4 inches long. The spatas are fused on both sides. The stems of the male flowers are 1.2 to 2.5 inches long. There are 9 stamens . The female flowers are almost sessile. They have 7 or 8 styluses . The fruits are light green to yellow-green or red. They have a diameter of 1.5 to 2.5 centimeters and 5 to 8 opening fruit flaps. The beak is 4 to 7 millimeters long.

The flowering period extends from spring to summer.

The number of chromosomes is 2n = 18.

distribution

Thalassia testudinum occurs from the USA (Florida, Alabama, Louisiana and Texas) and Mexico via Central America and the West Indies to South America (Colombia, Venezuela). The species grows on the seabed made of organic material, rocky material, coral sand or dead coral reefs from sea level to 10 meters deep in very clear water.

ecology

The species is possibly one of the most important marine seed plants on the coasts of the Caribbean and Gulf of Mexico, for example for substrate stabilization. In areas with stocks of Thalassia testudinum, for example, very little substrate is lost during a hurricane compared to areas without the species. This is achieved by the roots and rhizomes that hold the substrate in place and the leaves, which reduce the flow speed of the water .

Systematics

Thalassia testudinum was first described in 1805 in an article by Charles König who ascribed the name to the botanist Joseph Banks because his description was based on herbarium material and unpublished manuscripts from Banks.

literature

• Robert R. Haynes: Thalassia testudinum . In: Flora of North America Vol. 22 Hydrocharitaceae . ( online )

Web links

Commons : Thalassia testudinum  - collection of images, videos and audio files

• Thalassia testudinum inthe IUCN 2013 Red List of Threatened Species . Posted by: Short, FT, Carruthers, TJR, van Tussenbroek, B. & Zieman, J, 2010. Retrieved September 16, 2013.

Individual evidence

1. ^ Tropicos. [1]
2. ↑ Rafaël Govaerts (Ed.): Thalassia - World Checklist of Selected Plant Families of the Royal Botanic Gardens, Kew. Last accessed on June 20, 2018.
3. ^ Original description in Annals of Botany