Dendrobium discolor var. broomfieldii

Dendrobium discolor / Durabaculum undulatum.

An Antelope orchid, native to Queensland among other places.
There are five named varieties and subspecies – Dendrobium discolor var. broomfieldii,
    var. fimbrilabium, var. fuscum and subspecies D. incurvata and D. discolor.

There are many synonyms including:

• • Dendrobium species broomfieldii, arachnanthe, elobatum, fuscum and undulans.
  • Dendrobium undulatum and its varieties – var. albertisianum, var. fimbrilabium,

      var. broomfieldii, var. gracile and var. carterae.

  • Dendrobium discolor var. broomfieldii and D. discolor subsp. incurvata.
  • Callista undulata.
  • Durabaculum species albertisiana, arachnanthe, undulatum, fimbrilabium and fuscum.

   

  It has a variable appearance and some suggest that the varieties are just part of that variation.

  Dendrobium discolor var. broomfieldii or Durabaculum undulatum var. broomfieldii.
  It is known as the Golden Slipper orchid.
  An epiphytic or lithophytic orchid which forms large clumps anchored by roots from
      the bases of the pseudobulbs.
  Erect, arching, cane-like pseubulbs grow from a few cms up to 5 m tall.
  They have papery bracts when young and may be striped.

  There are up to 35 leaves, in 2 ranks, over the upper 2/3 of the stem.
  They are elliptic to ovate, up to 20 cm long, with bases that sheath the stem.
  They are dark green or yellowish and the tip is notched.

  Up to 6 axillary inflorescences arise from the upper nodes of the stem.
  They are erect or arching, up to 60 cm long with up to 80 resupinate flowers.
  There are papery bracts.

  Star-shaped flowers, up to 8 cm across come in bright or greenish-yellow, cream
      or brown, with areas of brown or lilac.

  Sepals are up to 35 mm long, narrow, twisted and with wavy edges.
  The dorsal one curves backwards.
  The lateral ones are widely spread and their bases, fused to the base of the column,
      form a small spur up to about 1 cm long.

  Narrow petals, up to 40 mm long, are twisted up to 4 times and have a wavy margin.
  The 3-lobed lip is up to 2.5 cm long by 1.5 cm wide.
  The margins of the large, outcurved side lobes have small, irregular teeth.
  The small middle lobe is triangular to ovate with a wavy margin.
  There are purple veins and 3-5 prominent whitish ridges on the lip.

  The column, up to 6 mm long is on a long foot.
  Dehiscent capsules are erect or drooping.

  J.F.