About Caladenia filifera Lindl.
Caladenia filifera is a terrestrial, perennial, deciduous herb that grows from an underground tuber, and often forms clumps or tufts. It produces a single erect, hairy leaf that measures 60–150 mm (2–6 in) long and 2–4 mm (0.08–0.2 in) wide. Up to three blood red flowers are borne on a stalk 150–350 mm (6–10 in) high; each flower is 100–120 mm (4–5 in) long and 60–80 mm (2–3 in) wide. The dorsal sepal is erect, 50–100 mm (2–4 in) long and 2–3 mm (0.08–0.1 in) wide at its base. The lateral sepals and petals are similar in size and shape to the dorsal sepal, but are held horizontally near their bases before tapering to thin, wispy, drooping tips. The labellum is 10–15 mm (0.4–0.6 in) long and 6–10 mm (0.2–0.4 in) wide, and is entirely blood red with a few darker marks, and is sometimes white near its base. The sides of the labellum have short, blunt teeth, its tip curves downwards, and two rows of anvil-shaped calli run along its centre. Flowering occurs between August and October. This species, commonly known as the blood spider orchid, is distributed near Watheroo within the Avon Wheatbelt and Jarrah Forest biogeographic regions, where it grows in well-drained soils in forest and scrubland. Its flowering is stimulated by fires that occurred in the previous summer. It was once more widespread across a larger area, but its current distribution has been reduced due to changes in fire regimes.
