Caladenia hiemalis, commonly known as the dwarf common spider orchid is a species of orchid endemic to the south-west of Western Australia. It has a single, hairy leaf and one or two, cream-coloured flowers with a small, red-striped labellum. It has an early flowering period and its flowering is stimulated by summer fires. Description Caladenia hiemalis is a terrestrial, perennial, deciduous, herb with an underground tuber and a single erect, hairy leaf, long and about wide. One or two flowers long and wide are borne on a stalk tall. The flowers are cream-coloured with red markings and the sepals and petals have long, thread-like tips. The dorsal sepal is erect, long and wide at the base. The lateral sepals are about the same size as the dorsal sepal but curve stiffly downwards. The petals are long and about wide and held horizontally. The labellum is long and wide and white with red stripes. The sides of the labellum have short teeth and the tip of the labellum is curled under. There are two rows of six to twelve cream-coloured, anvil-shaped calli with red markings along the centre of the labellum. Flowering occurs from June to early August, often following bushfires the previous summer. Taxonomy and naming Caladenia hiemalis was first described in 2001 by Stephen Hopper and Andrew Phillip Brown from a specimen collected in the Gooseberry Hill National Park and the description was published in Nuytsia. The specific epithet (hiemalis) is a Latin word meaning "of winter" or "wintry" referring to the flowering period of this orchid. Distribution and habitat Dwarf common spider orchid occurs between Jurien Bay and Tenterden in the Avon Wheatbelt, Esperance Plains and Jarrah Forest biogeographic regions where it usually grows in wandoo woodland, usually in moist soil. Conservation Caladenia hiemalis is classified as "not threatened" by the Government of Western Australia Department of Parks and Wildlife. References hiemalis Orchids of Western Australia Endemic orchids of Australia Plants described in 2001 Endemic flora of Western Australia Taxa named by Stephen Hopper Taxa named by Andrew Phillip Brown