Christmas Bells

Christmas Bells
Christmas Bells - Blandfordia nobilis

Saturday, February 05, 2011

The Tallong Midge Orchid.

Corunastylis plumosa, the Tallong Midge Orchid was in flower today. Actually we only found a single plant, but it is at least "a" record.
Tallong Midge Orchid - Corunastylis plumosa
The back story of this is that Alan Stephenson and I have been to the moss-covered rock shelves at Tallong each February and March since 2007, looking for the Tallong Midge Orchid. Each time we found other Corunastylis species, but not the elusive Corunastylis plumosa.

We felt that perhaps we had been too late (in those years). So this year, we decided to go to Tallong on the first weekend of February.

This plant has a very restricted distribution, being known only from these few hillsides in Tallong, these days. It was originally reported from Kurnell, in an area of coastal heathland. But Kurnell has been turned into Oil Refineries and houses.
Today the Tallong Midge Orchid is listed on the Endangered Species list of NSW as "critically endangered". It is listed as "Endangered" on the Federal Endangered Species list under the EPBC Act (under the old name, of Genoplesium plumosum). 
And so it ought be.

Today, at Tallong, the weather was stinking hot, probably 35 degrees, with a hot north-westerly wind blowing. After heavy showers over the last few evenings, it was very humid. With the weather "against us", and not being able to find any Midge Orchids at all, and felt very discouraged. 

Habitat of the Tallong Midge Orchid.

We decided to try looking in another patch of this low twiggy heath-shrubbery, across the road. 
Kunzea shrubbery.
As we walked down the hill, to cross to the opposite hillside, I suddenly spotted this purplish Midge Orchid. Instead of growing in under the Kunzea plants, as we were told they like to do, this plant was growing right out in the open, in a patch of moist grass.

Immediately we got out the 10 power hand lenses, with which to confirm the critical details of the flower anatomy, and to confirm the identification of this plant as the long-awaited Tallong Midge Orchid, not another species in that genus.
  • it has a clean edge to the dorsal sepal (far left of image), not a ridge of stiff fibres.
  • the labellum is heavily fringed, and is dark purple on top.
  • the base colour of the plant is green, but it is heavily striped purple. It is considerably darker in overall appearance than the closely related Corunastylis sagittifera (which is primarily a yellow-green flower, with some darker elements). (Compare this image). C. plumosa is not as dark as some other species of Corunastylis.
  • the lateral sepals are 'horn-shaped", as is its cousin, C. sagittifera.
  • Alan measure the plant at 178mm, with the flower spike itself being about 25mm long.
Rear of flower - Corunastylis plumosa
This is my favourite image of this rare plant.

Corunastylis plumosa - the Tallong Midge Orchid.
This plant is so uncommon that, from a quick Internet Search I could only find two images of this species, taken by John Briggs, the Threatened Species Officer of DECCW, for the Southern Tablelands region. Hopefully after tonight, it will appear more easily from a Google Image Search.


mick said...

Patience paid off! Congrats on finding this beautiful little orchid. IMO it's extreme dedication going out in conditions such as you describe!

Denis Wilson said...

Thanks Mick.
Yeah, dedication, or is it obsession?
At least it is not just me. There were two of us out there.