Idiospermum

Idiospermum austr Aliense

Idiospermum austr Aliense is the only species of the genus Idiospermum in the family of spice bush plants ( Calycanthaceae ). It is a very original, endemic species in Australia.

Features

Idiospermum austr Aliense is reached an evergreen tree, the plant height of 20 to 30 m. The nodes are unilakunär with a leaf-trace strand. The opposite, stalked leaves are simple and leathery; they have a smooth margin. The leaves have the mesophyll spherical cells with essential oils.

The flowers are single or a maximum of three in leaf axils. The flower stalk has several bracts. The most androgynous (there is a population in the all-male flowers occur ) flower is constructed acyclic, the flower organs are thus arranged spirally. The 30 to 40 free bracts change from outside to inside continuously from calyx -to kronblattartig; they are initially white later red. While the outer drop, the inner 15 to 18 remain. Of the 25 to 100 ( many ) free, flattened stamens are only the outer 13 to 15 fertile; especially the staminodes look like bloom. There are one or two ( or five ) free, upper permanent carpels present. The outer integument of the ovule is 12 to 15 cells thick ( crassinucellat ). The scar is fleshy and sits almost directly on the ovary. Pollination is by beetles and thrips, which (especially their pups) eat pollen and parts of the petals ..

The spherical, heavy, poisonous fruit is about 8 inches tall and is divided into four segments. The (three to ) four cotyledons are well trained and shield-shaped.

Idiospermum austr Aliense has no flavonols, but comes luteolin before. The tubes have stepped ( skalariforme ) perforations.

Occurrence

Idiospermum austr Aliense is in the rainforests of northeastern Queensland (Australia) in two small areas endemic. The populations of the two regions differ significantly.

Systematics and botanical history

The species was first described by Diels in 1912 as Calycanthus australiensis ( Botanical yearbooks for Systematics 48, p 10).

The next hit was again until 1971, when the poisonous seeds were the cause of the deaths of four cows. After the subsequent researches the nature of Blake in 1972 was placed in a separate genus ( Contributions from the Queensland Herbarium, 12, p.5). Blake it was also in their own family Idiospermaceae, today the species is, however, placed in the Calycanthaceae family, even if they somewhat isolated from the other genera is here.

Sources and further information

• The genus Idiospermum in the family Calycanthaceae in APWebsite (English )
• The Idiospermaceae on DeltaIntKey family.
• Australian Plant Name Index.
• Information on Art (English )
• Entry in GRIN.