Overview
The Green-comb Spider Orchid (Caladenia longifimbriata) is an exquisite terrestrial orchid native to the windswept south coast and sub-coastal sandplains of Western Australia. Distinguished by its lime-green to yellowish flowers and a remarkably wide labellum fringed with extraordinarily long, comb-like green teeth, this spider orchid is a quintessential element of the Esperance coastal heathland flora.
Biology and Physical Characteristics
Caladenia longifimbriata produces a solitary erect hairy leaf up to seven inches long from a subterranean tuber. The flowering stem holds one or two striking blossoms characterized by spreading greenish-yellow sepals and petals with narrow red-brown central stripes. The labellum is extraordinarily broad, green with a dark maroon recurved tip, and lined along its lateral margins with exceptionally long, narrow, green comb-like fringing teeth that give the species its botanical name ‘longifimbriata’ (long-fringed).
Behavior and Ecology
Flowering from September to November, Caladenia longifimbriata reproduces via sexually deceptive pseudocopulation. The flower emits chemical volatiles that precisely imitate the female sex pheromones of thynnid wasps. When male wasps attempt copulation with the movable, comb-fringed labellum, the insect is pivoted against the column, achieving pollination with surgical accuracy.
Conservation and Human Impact
Caladenia longifimbriata is assessed as Least Concern, maintaining extensive and healthy populations within Cape Le Grand and Cape Arid National Parks. Management priorities focus on protecting coastal sand dune systems from severe erosion caused by unauthorized recreational vehicles, preventing weed encroachment, and maintaining natural fire regimes across the mallee heath.
Interesting Factoid
The Latin name ‘longifimbriata’ translates directly to ‘long-fringed,’ honoring the exceptionally long, hair-like green teeth that line the margins of the labellum like the teeth of a fine-toothed comb.
Last updated: October 2026