Wednesday, 10 October 2007

#32 More Spring Orchids

There are so many exceptionally beautiful and intricately detailed native plants, camouflaged amongst the undergrowth living secret lives. some of Australia's ground orchids could have been designed by the wildest imaginations for a way-out science fiction or fantasy film, so weird and complex are their flowers.

No, this is not some man-eating plant with a tentacled tongue ready to pounce. It is one of Australia's amazing orchids unfurling - Purplish Beard-orchid, Calochilus robertsonii.

I have done some serious and extremely enjoyable orchid hunting in the Hunter Valley recently, and have found some fabulous plants. It's always a thrill to 'discover' species I have not previously seen. The Copper Beard-orchid, Red Beard-orchid and Purplish Beard-orchid are three of my October finds.

Calochilus paludosus - Red Beard-orchid

When I first saw the Red Beard-orchid while walking one of the bush tracks at the Hunter Region Botanic Gardens, my excitement bubbled over. I have since seen it in the Cessnock area of the Lower Hunter Valley.

The three Beard Orchids that I'm featuring here have slight, but distinctive differences enabling them to be distinguished. The differences mainly lie in the labellum and column.

Red Beard-orchid, Calochillus paludosus has a slender whitish-green scape (stem) to about 350mm tall, with an erect, linear, three-cornered (channelled) basal leaf and 1 or 2 stem bracts. Flowers are greenish with reddish stripes. The triangular labellum (tongue or lip) bears course, crinkled red to copperish hairs and a long creased ribbon-like tail. The flower is 20 to 25mm wide.

I have found this plant growing in sandy soil amongst leaf litter in open Eucalypt forest, hard white clay, and gravel embankment. More information at PlantNET.

Red Beard-orchid (Calochilus paludosus), on the left; and Purplish Beard-orchid (Calochilus robertsonii) on the right. The most noticeable differences occur at the base of the labellum. Notice that the Purplish Beard-orchid has two dark glands (dots) at the base of the labellum, either side of crowded shiny glands. If the picture was magnified, you would notice the two prominent dark glands are connected by a raised reddish ridge. Notice that the interior of the dorsal sepal (upper back) on the Red Beard-orchid is green, while the interior dorsal sepal of the Purplish Beard-orchid is marked with vein-like reddish-purple markings.

Copper Beard-orchid (Calochilus campestris) also has the two dark glands (resembling eyes) at the base of the labellum, but is easily distinguished by the raised metallic blue or purplish markings.

This image (below) of the back of the Beard-orchid flower shows the positioning of the sepals and petals. The broad petal-shaped vertical section is the dorsal (upper back) sepal; the two stiped, horrizontal side-facing sections are the petals; and the two downwards facing sections are the lateral (side) sepals. An easy-to-follow description of the positioning of similar orchid parts can be found on my Orchid Biology blog entry.

Also noticeable in the photo above, is the creased labellum 'tail'. From my brief observations, it appears that this tail is longest in the Red Beard-orchid.

Calochilus robertsonii - Purplish Beard-orchid

I have seen more of this species than the other two. The stiff, slender, single stem is the same colour as that of the Red Beard-orchid and can be between 200 and 400mm high, with one linear, channelled green leaf. It has between 2 and 4 stem bracts.

The labellum has long lustrous purplish hairs, becoming shorter, thicker and gland-like at the base below the column. It has a relatively short, crooked strap-like 'tail'.

I have found this plant growing in grass over hard white clay, gravel embankment, moss over damp soil, and grassy soil in eucalypt forest. More information at PlantNET.

A side view of the Red Beard-orchid (Calochilus paludosus) shows the long creased 'tail' on the tip of the labellum. Although the dorsal sepal (upper back) is depressed in this instance, it is usually erect and slightly 'hooded'. Also notice one of the stem bracts.

Notice the shorter 'tail' at the tip of the labellum of the Purplish Beard-orchid (Calochilus robertsonii). Also notice that the purplish vein-like markings on the side petals are definite lines, whereas the markings on the petals of the Red Beard-orchid (above) are thicker and irregular.

And notice that the side petals of the Copper Beard-orchid (Calochilus camperstris) below appear only to have the reddish markings on the interior and not the exterior (as in the two pictures above). You will also notice the short, stumpy, crumpled 'tail' of the curled-under labellum. The differences are subtle, but important for identification purposes.

Calochilus campestris - Copper Beard-orchid

I have only found one plant, so I consider it a very fortunate find. This is a robust plant, usually 300 to 500mm high, although the plant I found was only 200mm. It has a deeply channelled leaf and two green or coppery stem bracts.

Flowers are in a raceme of about 5 to 15. They are yellowish green with red-brown or purplish markings and a labellum that is shorter than the other two species. It is about 15mm long, triangular, sometimes with a short strap-like tip, and rather sparse coppery red hairs. There are dark shiny glands in both lower corners of the column, and smooth metalic blue or purplish raised linear markings at the base of the labellum.

The single plant I found was growing amongst sparse grasses over hard white clay. More information at PlantNET.

Purplish Beard-orchid

I'm sure you'd agree now, that there is nothing plain or boring about our native orchids. I am not aware if there is a specific insect which pollinates each species, or a range of small insects. I presume the 'beard' serves a purpose. As I learn more about these fascinating plants, I will share my observations and collection of information from those more experienced than I.


Esperance Blog said...

Hi Gaye, some great photos of some spectacular orchids. There are three Calochilus species in WA, but these are poorly known and very difficult to locate. Finding them here is made even more difficult by their habit of not flowering regularly, often missing years. So very much a case of being in the right place at the right time.


buffy said...

It seems from my reading of Corrick and Fuhrer that down here in Victoria we have only one Calochilus - campestris. I have not seen any myself. They do seem very strange flowers. Wonderful pictures Gaye.

Denis Wilson said...

Hi Gaye

Well done with the Bearded Orchids. I have not found the Copper Beard Orchid (C, campestris) here. I shall be out looking for them in about 2 weeks - which seems to be about the lead time between your area and mine.

The colour names are not very satisfactory, I find - (red, purplish and copper).

Stunning photos, especially the close-up of the "tongue and face and eyes" of C. campestris. It looks like a "print quality" photo to me. Wonderful shot.

Gaye from the Hunter said...

hi Jack,

I would be most interested to see pictures of the WA Beard Orchid species if you come across them at some time. I have found that searching for orchids is certainly hit and miss. I'm keeping a diary of locations and dates of flowering (a GPS would be most useful, though). I will try to monitor my finds from year to year.


Gaye from the Hunter said...

hi buffy,

thank you for your comment. I do hope you can find your local species to see first-hand the beauty of the odd details.


Gaye from the Hunter said...

hi Denis,

thank you, and I'm glad you enjoyed my orchids. Alas, my pictures are mostly taken by my compact 'point-and-shoot' digital which is only 3.2 megapixels, so they are not of good print quality, but do the job for sharing the beauty and detail via the internet.

Good luck with your orchid hunting.


Anonymous said...

Hi Gaye,
Your first photo deserves a comment for you were certainly there at the right time to capture that unfurling orchid. A great blog with your usually splendid photos.

Gaye from the Hunter said...

hi Lola,

thank you. I never tire of the beauty that we walk amongst every day, but extraordinary things like the unfurling of a bud is special.