About Arthrochilus prolixus D.L.Jones
Arthrochilus prolixus is a terrestrial, perennial, deciduous, sympodial herb that grows from an underground tuber, which produces daughter tubers at the end of root-like stolons. It forms a rosette of 2 to 6 linear to lance-shaped leaves on a side branch at its base. Each leaf measures 40–70 mm (2–3 in) long and 7–15 mm (0.3–0.6 in) wide. Between 3 and 22 pale green, insect-like flowers, each 10–16 mm (0.4–0.6 in) long, grow on a flowering stem 80–200 mm (3–8 in) tall. The dorsal sepal is linear, 9–10 mm (0.35–0.39 in) long, about 2 mm (0.08 in) wide, and partially wraps around the base of the column. The lateral sepals are lance-shaped, 6–7 mm (0.2–0.3 in) long, and about 2 mm (0.08 in) wide. The petals are linear, about 7 mm (0.3 in) long and 1 mm (0.04 in) wide. Both the lateral sepals and petals are turned back against the ovary. The labellum is about 6 mm (0.2 in) long and 1 mm (0.04 in) wide, attached to a stalk or "claw" that is about 4 mm (0.2 in) long. It bears an insect-like callus about 3.5 mm (0.1 in) long, with dark reddish brown hair-like glands arranged in a central band. The tip of the callus is about 2 mm (0.08 in) wide and holds shiny black glands. The column is light green to whitish with purplish spots, strongly curved, and has two pairs of curved wings. Flowering takes place from December to February. This orchid, commonly called the wispy elbow orchid, grows among grasses and shrubs in forested areas between Manly in New South Wales and south-eastern Queensland. The largest known population of this species is located in the Bulahdelah district. One colony has become established in rotting sawdust at a sawmill. Like other orchids in the genus Arthrochilus, A. prolixus is pollinated by male thynnid wasps of the genus Arthrothynnus, though the specific wasp species involved has not been identified. It also reproduces asexually by growing new tubers.
