Christmas Bells

Christmas Bells
Christmas Bells - Blandfordia nobilis

Tuesday, September 21, 2010

Bird Orchids are back!

I have posted about these little charmers previously, but I am going to write them up again, because they are special.

They are highly localised plants, occurring in an area just near Robertson, on the Budderoo Plateau.These Bird Orchids get their name from the manner
in which the flower is held high,
resembling the open beak of a small bird, begging for food.
There are a number of closely related species, in other areas.
This is the only one I have seen.

This Bird Orchid is known as the "Wollongong Bird Orchid", the Green Bird Orchid, or Simpliglottis chlorantha (or Chiloglottis chlorantha).

It is found here on the Budderoo Plateau, and further south to the Budawangs. There may be some records from the Blue Mountains.


Botanical Illustration courtesy of PlantNET

Although David Jones mentions this locality in his book as Knights Hill (approx 6 Kms away), that reference is quite misleading. Knights Hill is a basalt capped mountain, with tall, wet Eucalypt forest, whereas these plants grow on shallow, sandy, peaty soil over a shallow sandstone rock shelf. They grow amongst small "heath" vegetation. In fact, they are quite hard to find, because of their tendency to grow in and amongst these low shrubby plants. One can clearly see Knights Hill from where these plants grow, but that's about all one can say in favour of that "location" note. Budderoo Plateau would have been a much better location descriptor.

You could hardly get more different habitats than Knights Hill (with a 30 metre canopy of Eucalypts and Sassafras), and where these plants are, growing under and amongst heath plants scarcely 30cm high.

Here is a close up of the Labellum.
The botanical description says: "Labellum cordate, 12–13 mm long, 9–12 mm wide, with c. 12 linear to terete, erect or curved calli on the basal two-thirds, the largest c. 3.5 mm long."

I prefer to describe the pale green, almost "luminous" green glands (calli) towards the tip of the labellum as looking like blobs of soft jelly. There are two large ones, and two small upright ones, flanking them. Behind the green glands are a series of upright glands, which look like they are made of red jelly. From the front-on view, these structures vaguely resemble chess pieces in some bizarre Chess Set, perhaps from an Alice in Wonderland story.

In the typical positioning of Chiloglottis Orchids, the column is held high, but directly above the labellum, ready to dob the sticky pollen grains on the back of a wasp which tries to mate with the flower (which smells like the female wasp).

Interestingly, the Labellum although looking quite stiff, is actually very lightly "hinged" and the labellums *** of these flowers were trembling in the warm breeze today.

This specimen has given its pollen away already,
to an unsuspecting wasp. one assumes. The yellow housing for the pollen is now empty,
and the receptive female part of the flower is clearly exposed.

Compare this flower (complete with pollen grains still present)
with the empty one, above.
This flower has an ant crawling across it, (click to enlarge image)
but the ant is not the suitable pollinator for these flowers.

*** Please forgive the use of the word "labellums", but "labella" seemed pretentious, and liable to confuse.

6 comments:

mick said...

Dainty and intricate little beauties! I don't mind seeing more than one post about a special orchid. After all this is a blog and not a text book!

Flabmeister said...

As usual an excellent post. We have indications - ie leaves - of many orchids on our property this year. So far none of them have got beyond poking up buds. I am hopeful that the warm weather forecast for the next few days will do the job. Then comes the task of identifying them!

Martin

Flabmeister said...

Denis

I was a tad previous with my earlier post. After submitting that I took the small dog for a walk and came across a couple of blue "not-caladenias". (I haven't time right now to work out what the taxonomists are calling them this week). Then went back to show Frances and found about 50 of them. A post will be perpetrated on House of Fran_mart this afternoon.

Not as exciting as your sighting, but this is the first time we have found more than one of these on our place.

Martin

Denis Wilson said...

Hi Martin
Your blue "non-Caladenia" is probably Cyanicula caerulea (this week).
I wrote about it when I saw it at Albion Park for the first time three weeks ago
Hard part is to capture the true colour - blue not purple.
Best of luck.
Fifty of them - that's great.
Denis

Denis Wilson said...

Hi Martin (again).
I just went out for a while and found lots of tiny (2 inch high) purple-blue Orchids, but they are Glossodia minor. try this link.
.
The difference is in the shape of the labellum - this one is triangular, with two little black glands on top (like dog's balls - I would have to say).
.
The other non-Caladenia has a curved down labellum, and yellow dots in that "insect landing lights" pattern.
Both small, both blue-purple. Both flower early. Makes it hard for us.
Cheers
Denis

Denis Wilson said...

Hi Mick
As ground orchids go, this one has a relatively large flower - on a very short stem (2 inches only).
.
Thanks for commenting that I am allowed to repeat myself. After all, the seasons do.
Cheers
Denis