Dendrobium jonesii

Dendrobium jonesii is an epiphytic or lithophytic herb with dark brownish green pseudobulbs that are 200–500 mm (8–20 in) long, 30–40 mm (1–2 in) wide and tapered at both ends. There are between two and seven thin, leathery, dark green leaves 60–150 mm (2–6 in) long and 40–60 mm (1.6–2.4 in) wide. Between ten and thirty five cream-coloured or white resupinate flowers 16–20 mm (0.6–0.8 in) long and 20–25 mm (0.8–1 in) wide are borne on a flowering stem 200–350 mm (8–10 in) long. The sepals and petals are pointed, the sepals 16–22 mm (0.6–0.9 in) long and 2.5–4.5 mm (0.1–0.2 in) wide and the petals a similar length but narrower. The labellum is white with purple markings, about 8 mm (0.3 in) long and 7 mm (0.3 in) wide with three lobes. The side lobes are curved and the middle lobe is oblong with an orange ridge along its midline. Flowering occurs from July to November.[2][3][4]

Dendrobium jonesii was first formally described in 1901 by Alfred Barton Rendle from a specimen collected by "Mr. Arthur Owen Jones, J.P.". The description was published in the Journal of Botany, British and Foreign[5][6] and the specific epithet (jonesii) honours the collector of the type specimen.[6]

There are two varieties:

• Dendrobium jonesii var. jonesii;[7]
• Dendrobium jonesii var. magnificum (Dockrill) Dockrill[8] – the large oak orchid which has larger flowers and a later flowering period.[2]

The oak orchid grows in rainforest and in open forest where it often grows on she-oaks (Casuarina species) between the Iron Range National Park and Paluma. The variety magnificum grow at higher altitudes in the southern part of the species' range.[2][3][4]