"rufa Greenhoods" - another "first" for me

Today I went to Yalwal, south-west from Nowra, to a place where Alan Stephenson had showed me last autumn. The reason? To see the Oligochaetochilus rufus (otherwise known as Pterostylis rufa) which are to be found in this spot.

This is the first time I have seen this species, in flower.

When I first "got into" Orchids I became fascinated by the many shapes of Greenhoods, and then I discovered that some "greenhoods" were red. That's when I first realised the mystery of Greenhoods - which lay in front of me.

Regular readers will recall that I published a post about the "Gibbosa Greenhoods" several weeks ago. And then the related "bicolor Greenhood" the next day. Both those plants are related to this plant, which is the "nominate species" for what is known in Orchid circles as the "rufa group" of Greenhoods. Yet the similarities are not in colour (for both those two plants are green). No, the primary similarities lie in the shapes of their "labellums" and their dome-shaped "hood" (galea) and the wide flange under the galea which is nearly closed off. There are other factors, such as the leaf rosettes and the sheathing stem leaves. Anyway, that's all getting a bit technical - sorry.

To me, this is a very exciting "first" for me, because these plants are quite iconic for me, for the reasons given above. So lets look at the plants themselves.

Oligochaetochilus rufus - a profile view.
Note the deflexed lateral sepals underneath the hood.Here is a lovely plant with three flowers and several buds yet to open.
It is relatively tall for this species,
but it is still only about 6 inches high (12 cm approx).

Here is a lovely pair of plants growing in close proximity.
These were barely 4 inches high.
The open flowers were even lower than that (buds above yet to open).

Here is the most distinctive feature of this plant
- the labellum with stiff hairs.
These hairs are long, all around the sides and the lower edge.
There is a band of short stiff hairs across the upper edge of the labellum.

Here is the botanical illustration for this species from PlantNET.
Here is my best cropped image of the "labellum".
You can see how well drawn is the image above.
Here is another plant with the labellum having been triggered (closed).
You can see the yellow "hinge" of the labellum,
which is now closed right up inside the galea.
With the stiff hairs all around the labellum,
any insect which might have triggered the movement sensitive hairs
would be "imprisoned" inside the galea,
being unable to squeeze out past these stiff hairs.
The labellum relaxes and opens after some time, freeing any insect
which might have been trapped inside.
That is a technique designed to help the plant achieve pollination.

The "gibbosa" had a quite different shaped labellum.
It had only two of these long, stiff hairs.