Actinostrobus
The scales cypress ( Actinostrobus ) are a genus of trees in the family of the cypress family ( Cupressaceae ). The three species of the genus live in a narrow band along the west coast of Australia.
Description
Shed cypress are evergreen, monoecious shrubs or trees with smooth, thin, flaking bark. The branches are short and strong and form a conical or shrub -like crown. Even trees with hanging crown occur naturally.
The leaves are in threes downwards in whorls. Young leaves of young trees grow acicular. The adult green or Glauk - green leaves are usually shorter than 5 millimeters, have a linear - lanceolate in shape and thorn - pointed. The lower leaf surface is keeled, serrated leaf margin. Occur in two bands with stomata on both leaf surfaces.
The pollen cones are small and cylindrical. The 10 to 18 Mikrosporophylle are in groups of three whorls, and have two to four abaxial pollen sacs. The seed cones are individually, in groups of two to groups of three or heaped along branches. Closed they are approximately spherical in shape with hemispherical tip, spherical - conical or globular - tubular. The bracts are arranged in two whorls to three equally large scales, which are compared with four to six leaves shed. The bracts tips are completely covered by the seed scales. The seed scales are oblong with bright seed scar at the base. The ovules stand erect in the axils of the bracts in two whorls of four to six. The pin eight to twelve three-winged seeds are formed. The seedlings form two germ layers.
The chromosome number is.
Distribution and ecology
The distribution area extends in a narrow band along the west coast of Australia from the south of Shark Bay to Albany. The types Actinostrobus pyramidalis and Actinostrobus arenarius will do often preissii together with the Schmuckzypresse Callitris. Representatives of the two genera ( Actinostrobus and Callitris ) colonize as the only representatives of the conifers dry areas in Australia, thus taking it similar ecological niche as a juniper (Juniperus ) in the northern hemisphere.
System
The scales cypress ( Actinostrobus ) are a genus in the family of the cypress family ( Cupressaceae ). The genus can be divided into three types:
- Actinostrobus acuminatus Parl: Older plants show both young, needle-like and scale-like leaves older. Seed cones grow not in groups.
- Actinostrobus arenarius CA Gardner: Mature plants bear only scale-like leaves, pine cones grow in groups, seed scales of the cones have a straight and pointed end.
- Actinostrobus pyramidalis Miq. Mature plants bear only scale-like leaves, pine cones grow in groups, seed scales of the cones have a rolled and blunt end.
The genus was first described in 1845 by Friedrich Anton Wilhelm Miquel in Plantae Preissianae. The genus name is derived from the Greek, actino stands for " ( light ) beam " and strobus for " pin ". The name thus refers to the six cone scales converge at the tap point.
Use
For none of the species use is known, they are hardly used as ornamental plants, even though they have some ornamental value due to their conical shape, the green color and the pin shape.