Caladenia clavescens is a plant in the orchid family, Orchidaceae and is endemic to central Victoria in Australia. It is a ground orchid with a single hairy leaf and usually a single dark red to maroon flower.
Caladenia clavescens is a terrestrial, perennial, deciduous, herb with an underground tuber and a single leaf, long and wide. One, rarely two flowers are borne on a spike high. The flowers are dark red to maroon, sometimes cream-coloured or pinkish with petals and sepals long. The sepals are wide, flattened near their bases but taper to a thread-like tip which is densely covered with glands. The petals are similar to the sepals but somewhat shorter. The labellum curves forward with the tip rolled under, and is broad lance-shaped to egg-shaped, dark purplish, long and wide. The sides of the labellum are fringed with linear teeth up to nearly long, decreasing in length toward the tip of the labellum. There are four to six rows of foot-shaped calli along the centre of the labellum and these are also about long near the base of the labellum and decrease in length towards its tip. Flowering occurs from September to October.
This orchid was first formally described by David L. Jones in 2006 as Arachnorchis clavescens and the description was published in Australian Orchid Research. The type specimen was collected near Castlemaine. In 2007, Gary Backhouse changed the name to Caladenia clavescens. The specific epithet (clavescens) is derived from the Latin word meaning 'club' and the meaning 'becoming', referring to the more or less club-like tips of the sepals and petals of many of the specimens of this species.
Caladenia clavescens occurs in central Victoria near the towns Campbells Creek, Castlemaine, Chewton.
This spider orchid is listed as "vulnerable" and is protected under the Flora and Fauna Guarantee Act 1988.