Alexgeorgea
Alexgeorgea
Alexgeorgea is a plant genus of the family of Restionaceae that occurs with three species in Western Australia. It was described in 1976 by Sherwin Carlquist and named after the Australian botanist Alexander Segger George.
Features
The plants have elongated, whitish rhizomes, which are about 10 centimeters below the surface and wearing shiny leaf shed. The rhizome branches out occasionally, especially at the points where the outstanding photosynthetically active green shoots arise on the earth's surface. These have tight-fitting sheaths, are longitudinally striped and can be hairy fluffy. You either have short, flattened side shoots or branches are cylindrical and multiply. Alexgeorgea are dioecious getrenntgeschlechtig ( dioecious ). The male plants bear multiflorous spikelets terminal on the shoot. A special feature of the genus are the spikelets of female plants that are located with a single flower directly on the rhizome, so that only the tips of the bracts and the three shiny long purple pen protrude above the surface. The unilocular ovary after fertilization forms a 10 to 15 millimeters in size, spherical or inverted - cone-shaped nut fruit.
Ecology
Alexgeorgea species grow in sandy soil in -moist or seasonally dry areas, often on ruderal sites. Propagation is probably mainly vegetatively on the growth of rhizomes. Pollination of flowers is done by the wind. In the germination of the seedling pushing the fruit upwards without this passes over the ground surface and forms an upwardly and shortly afterwards the first rung rhizome. The location of the female flowers below the surface and the underground germination could be adjustments to the frequent fires in Western Australia.
System
Within the Restionaceae the genus of the subfamily Alexgeorgea Leptocarpoideae and herein the Loxocarya group is assigned. Within the genus three species are described:
- Alexgeorgea ganopoda L.A.S.Johnson & B.G.Briggs
- Alexgeorgea nitens ( Nees ) LASJohnson & BGBriggs
- Alexgeorgea subterranea Carlquist