Overview
The Club-lipped Spider Orchid (Caladenia corynephora) is a distinctive and elegant terrestrial orchid endemic to the damp coastal swamps and river flats of southwestern Australia’s high-rainfall south coast. Distinguished by its extraordinary labellum, which terminates in a prominent, swollen, club-like dark glandular mass, this late-spring blooming spider orchid is a fascinating specialist of wetland ecotones, utilizing sophisticated chemical mimicry to seduce male thynnid wasps.
Biology and Physical Characteristics
Caladenia corynephora produces a single, narrow, hairy basal leaf that reaches up to eight inches long. In late spring and early summer (November to January), a tall, slender hairy flowering scape carries one to three showy flowers. The sepals and petals are creamy yellow to pale green with reddish central stripes; the sepals are long and drooping with dark glandular tips. The heart of the flower is its remarkable labellum, which features green comb-fringed side margins and curves downward into a swollen, glossy, dark purple-black club that looks and smells like a female wasp.
Behavior and Ecology
Like other Caladenia spider orchids, Caladenia corynephora practices sexual deception (pseudocopulation). The unique swollen club at the tip of the labellum is densely packed with specialized osmophore glands that secrete volatile chemical mimics of female thynnid wasp sex pheromones. Attracted by the scent, male wasps fly directly to the flower and grasp the swollen club, attempting to fly away with it. As the wasp grapples with the decoy, its thorax strikes the column, transferring pollen packets with precision.
Conservation and Human Impact
Evaluated as Least Concern, the Club-lipped Spider Orchid is well-represented within national parks and nature reserves across the Warren and South Coast regions, including D’Entrecasteaux National Park and Walpole-Nornalup National Park. Because it is strictly tied to peaty, winter-wet habitats, its greatest long-term vulnerability is the drying of southern wetlands caused by changing climate regimes, surface water extraction, and invasive feral pig trampling.
Interesting Factoid
Unlike most Western Australian spider orchids that finish blooming by October, Caladenia corynephora flowers exceptionally late, often peaking around Christmas in damp paperbark swamplands when other terrestrial orchids have already gone dormant.
Last updated: October 2026