Castanospermum australe is a flowering plant in the family Fabaceae, native to the east coast of Australia in Queensland and New South Wales, and to the Pacific islands of Vanuatu, New Caledonia, and the island of New Britain.
Castanospermum australe is closely related to the Sensitive Plant (Mimosa pudica) but not to the Chestnuts. The native to Australia tree belongs to the bean family (Fabaceae). In its natural habitat it reaches a height of 40 metres. The about 3-4 cm or longer poisonous seeds of the commonly known as Moreton Bay Chestnut or Australian Chestnut plant look similar to chestnuts – at least at first sight. It is the only species in the genus Castanospermum.