What makes an Orchid and Orchid?

Orchid flowers are extremely variable in appearance, ranging from mimicking spiders, flying ducks, helmets, ants, etc. This variety also can cause some confusion. People have mistaken a different type of flower for an orchid and vis a versa.

This raises the question of what makes an orchid an orchid? With so much variety, how can they possibly belong to the same family?

Using orchids found in the Adelaide Hills, the following video shows three key features that helps identify a flower as an orchid. These three features are found in all orchids worldwide.

So watch and enjoy …

Waiting for the rain …

Last year we waited for the rain. The rain heralds the start of the orchid season. Last year the season was dry, very dry. It was below average and it was hot.

So how did the orchids fare in the Adelaide Hills? The start of the season was slow with our first field trip not being until May 26 because of the lack of rain.

At the time, the smallness of the plants was noticeable with one specimen of flowering Leporella fimbriata standing no more than 2 cms. Normally  the flower stem can be up to 25 cms tall. This trend of smaller plants continued throughout the year.

The following two photographs show the difference in size.

Small Leporella fimbriata
A miniscule Leporella fimbriata near an ant nest

Leporella fimbriata sm

And on January 28, we came across the smallest flowering Dipodium pardalinum that we’d ever seen. Normally, this genus can grow up to about 100 cms in height but this one barely reached above the height of Robert’s shoe, ie, about 10 cms. True this was an exception but overall there not many plants, and even they were spindly and small in comparisons with previous years.

Below are two photographs illustrating the size difference

Small Dipodium pardalinum
A very tiny Dipodium pardalinum

Dipodium roseum
An average sized Dipodium

So what is the outlook for orchids for 2019? That will depend upon the rains.

When does the orchid season get going? Again that depends upon the rain but expect to see the autumn orchids about six to eight weeks after a good rain episode.

So we wait for the rains ….

2018 February Winning Photograph

1802 sm RP Caladenia carnea

A small but varied number of entries for our first competition of the year. Andrew Primer entered a lovely picture Thelymitra azurea from Eyre Peninsula; Thelma Bridle entered Calochilus cupreus one of South Australia’s endangered orchids; John Fennell’s close up of Caladenia prolata and Rob Pauley’s mass flowering of Caladenia carnea.

The winner was Rob Pauley’s C. carnea a wide spread orchid which ranges from across the Eyre Peninsula through to the South East as well as occurring in the Eastern States and Tasmania. Although considered common both nationally and at a state level, there are regions within its range where it is considered to be Near Threatened, Rare and even Vulnerable. Also, despite being common, the Seedbank notes that there are areas of probable decline: Fleurieu (KAN02), Mt Lofty Ranges (FLB01), Eyre Mallee (EYB05), Wimmera (MDD05) and Southern Yorke (EYB01). It is a reminder that not only the rarest species but also that common species can be in decline.

The situation is complicated by taxonomic issues; C. carnea is not only a highly variable species but also a complex of several similar species plus many undescribed species which continues to challenge botanists.

References:

http://saseedbank.com.au/species_information.php?rid=815 accessed 8 March 2018

Backhouse, G., et al, (2016) Bush Gems: A Guide to the Wild Orchids of Victoria, Australia, Electronic version.

Bates, R. J., ed. (2011). South Australian Native Orchids. Electronic version. NOSSA

Clarification of Pterostylis valida

Short Paper 3 Identity of Pterostylis valida (Orchidaceae) by Rudie Kuiter was published in June 2017. In this paper, Rudie has tackled the difficult group of Rustyhoods or Oliogochaetochilus (specifically Pterostylis valida) within the genus Pterostylis. Many of the different species occur in isolated pockets over a wide geographical range. Differences can be subtle but Rudie has sought to clarify the distinction between P. valida  and similar species. Click here read the complete paper.

A typical flower at the type-locality, green with the usual stripes on the transparent parts of the hood, cup-shaped synsepalum and dark labellum swellings. Opposite page Image of the original 1941 description page by Nicholls of Pterostylis valida as a variety of P. squamata. It was cropped with the deletion of the description of Caladenia hastata, the other species. 
A typical flower at the type-locality, green with the usual stripes on the transparent parts of the hood, cup-shaped synsepalum and dark labellum swellings. (Image from Rudie Kuiter’s Short Paper)

 

Corybas Pollinators

Rudie Kuiter’s Short Paper 5, October 2017, is about he and his team’s observations on the pollination strategies of fungus-gnats with Corybas. A small section from the introduction is quoted below:

Certain flowers in large colonies were most popular over several days and both sexes were observed feeding on the boss, which suggests a food-related attraction. Virtually nothing was known about the Corybas pollinators and primary literature to date only offered hypotheses. Based on our findings, the persisting statement in literature that ‘Corybas species attract fungus-gnats as putative brood-sites’ is incorrect for the taxa in Victoria. No evidence of ovipositing in flowers was found. Females feeding looked gravid and were presumed to be unfertilised. All individuals looked fresh with undamaged wings and it was apparent they had recently hatched.

Is this a hypotheses that needs revising? Rudie definitely demonstrates the importance of careful and meticulous observations.

Click here to read the full article

Corysanthes diemenica 077
Corysanthes diemenica (Veined Helmet Orchid)

2017 September Winning Picture

1709 sm JF Thelymitra x truncata

 

Natural hybrids are both fascinating and challenging. Fascinating because they don’t occur readily, (although of all the plant families, orchids have one of the greatest propensity for hybridising). Challenging because of the difficulty in determining the parents unlike the manmade hybrids where we can track which parents are being used to make the hybrid.

Obviously, the hybrid will share characteristics of both parents and this is the case of this month’s winning photograph, John Fennell’s Thelymitra x truncata. In the South Australian setting, a spotted orchid hybrid suggests that one of the parents will always be T. ixiodes/juncifolia and because it is blue it is most likely that the other parent will also be blue, from either the T. pauciflora or T. nuda complexes. This is true also for T. x merraniae. This is because there is no naturally occurring blue pigment. Whereas a pink or yellow parent and a blue parent will not produce a blue hybrid. Consider T. x chasmogama, T. x irregularis, T. x macmillanii are never blue.

Finally, it is fitting that this should be the winning photograph as this is the centenary month (September 2017) of its presentation to the Royal Society of South Australia, by Dr R S Rogers who also named this hybrid. The other hybrids entered were Jane Higgs Caladenia Harlequin and Diuris Earwig, both cultivated plants; Pauline Meyers Caladenia falcata X Drakonorchis barbarossa; John Fennell’s Caladenia x idiastes, T. x irregularis; Rickey Egels T. x macmillanii along with Lorraine Badger’s Caladenia roei hybrid and Caladenia x ericsoniae.

Reference

https://www.biodiversitylibrary.org/item/109628#page/353/mode/1up

https://nossa.org.au/2017/07/28/2017-june-winning-picture/

https://nossa.org.au/2014/09/26/thelymitra-x-irregularis-beautiful-but-only-a-hybrid/

Bates, R. J., ed. (2011). South Australian Native Orchids. Electronic version, 2011. NOSSA

Rules of entry:

The subject matter must have something to do with Australian orchids.  Any format is acceptable including Photo shopped images, artwork, etc

 

Orchids In Remnant Roadside Vegetation

This week’s post written by Leo Davis is an article (slightly edited) from The South Australian Naturalist 91 (1): 34 – 37 January – June 2017. In this article, Leo highlights the importance of  the role of roadside vegetation in preserving the native orchids and flora.

All photographs are by Leo Davis.

Microsoft Word - SAN Vol. 91, No. 1, Jan-Jun 2017  pp. 34-37 OrcFig 1: Thelymitra antennifera hybrid

One of my rules of thumb is ‘If I am in a Conservation Park, I’m on ground that nobody could make a living from.’ One, usually more, of nutrient poor soils, excess salinity, extreme rockiness, steepness, poor moisture retention, low rainfall or even being waterlogged, will be a feature of the location. There are a few odd spots that have survived partly intact, that have good soil, sufficient rainfall, etc. These include cemeteries (The Nationally Critically Endangered ghost spider orchid (Caladenia (syn. Arachnorchis) intuta) holds on in a cemetery on Yorke Peninsula) or exclusion zones around water storages (including a reservoir reserve in Lobethal that the public can now access) or abandoned railway yards (including Sherlock, where so far I have found 21 species of orchids and part of a reserve in Halbury.)

Microsoft Word - SAN Vol. 91, No. 1, Jan-Jun 2017  pp. 34-37 Orc

Fig 2: Little Yellow Club Mallee Spider Orchid Caladenia (syn Arachnorchisverrucosa

When I go in search of plants with the Botany Group of the FNSSA (Field Naturalist Society of South Australia), or for orchids with NOSSA (Native Orchid Society of South Australia), or when I do surveys of threatened orchid species with DEWNR (Department Environment, Water and Natural Resources), or orchid seed collection with the Adelaide Botanic Gardens, or go on weeding parties to protect endangered species, the destination is always one of these deprived, rejected sites. The orchids I see are those adapted to or just hanging on in such sites. We never see orchids that lived on better soils, say on the Adelaide Plains. How many have become extinct?

Microsoft Word - SAN Vol. 91, No. 1, Jan-Jun 2017  pp. 34-37 Orc

Fig 3: Common Mallee Shell Orchid Pterostylis dolichochila

Wherever the land was suitable for agriculture it was clear felled. Almost nothing of the original flora and little of its associated fauna, were left. But there is a tiny flimsy exception. Crossing these highly productive agricultural zones are roads and sometimes these have remnant vegetation. For a person interested in orchids, these narrow strips are normally areas of slim pickings but occasionally finds are made. Near Halbury, the Nationally Endangered Halbury rufoushood (Pterostylis sp. Halbury or Oligochaetochilus lepidus) can be found in some roadside spots.

Microsoft Word - SAN Vol. 91, No. 1, Jan-Jun 2017  pp. 34-37 Orc

Fig 4: Mallee Bearded Greenhood Pterostylis (syn Plumatichilos) sp. Mallee Bearded Greenhood

The most remarkable piece of roadside vegetation that I have come upon was discovered by and shown to me by Glenn Dean, the Environment Officer with the City of Murray Bridge. He found a section of predominantly broombush (Melaleuca uncinata) vegetation, only about 200 m. long, on the verges of a single car sandy track, east of Murray Bridge. It is so close to the vegetation that cars can be scratched. I have found 24 species of orchid (Glenn has found more) blooming there sometime between March and October each year. All images shown here (Figs 1–11) were made at this site. If the little used road was not there the land would have been under crop, being equal in quality to regularly cropped fields to either side, and is of much higher quality than any normally allocated to Conservation Park status. Most of the orchids found can indeed be found in some of the poor sites dedicated as Conservation Parks, including species similar to those found at Ferries McDonald and Monarto Conservation Parks with their poor sandy soils. But this spot, which for some reason supports species that do not grow just 100 metres east or west along the road, has such species as the Nationally Critically Endangered Mallee Leek Orchid (Prasophyllum constrictum) (Fig. 8), that requires soils as good as those demanded by wheat, so it is essentially doomed.

Microsoft Word - SAN Vol. 91, No. 1, Jan-Jun 2017  pp. 34-37 Orc

Fig 5: Rusty Rufoushood Pterostylis biseta (syn Oligochaetochilus bisetus)

Its single plant sighting here is regarded as a ‘rediscovery’ of a species not seen for years. In the longer term I guess this tiny site of orchid species richness is in a transitory state and most species will disappear. The surrounding cropping land is neither a source of seed nor a suitable landing site for it and it provides damaging wind blown nutrients and other chemicals. So I will cherish it while it lasts and hope others appear, if only briefly. Here is a reminder, that most of you do not need, of the value of roadside vegetation (with the understanding that it can contribute to native animal mortality) and that we should manage, extend and guard its presence.

Microsoft Word - SAN Vol. 91, No. 1, Jan-Jun 2017  pp. 34-37 Orc

Fig. 6: Rufoushood Pterostylis (syn Oligochaetochilus) boormanii complex sp.

Microsoft Word - SAN Vol. 91, No. 1, Jan-Jun 2017  pp. 34-37 Orc

Fig. 7: Cinnamon Donkey Orchid Diuris palustris

Microsoft Word - SAN Vol. 91, No. 1, Jan-Jun 2017  pp. 34-37 Orc

Fig. 8: Mallee Leek Orchid Prasophyllum constrictum

Microsoft Word - SAN Vol. 91, No. 1, Jan-Jun 2017  pp. 34-37 Orc

Fig. 9: Limestone Tiny Shell Orchid Pterostylis cycnocephala
(syn Hymenochilus calcicolus)

Microsoft Word - SAN Vol. 91, No. 1, Jan-Jun 2017  pp. 34-37 Orc

Fig. 10: Caladenia (syn Jonesiopsis) capillata x Pheladenia deformis hybrid

Microsoft Word - SAN Vol. 91, No. 1, Jan-Jun 2017  pp. 34-37 Orc

Fig 11: Small Rustyhood Pterostylis pusilla (syn Oligochaetochilus pusillus)


Returning the Water

Each month the Native Orchid Society of South Australia has a special speaker. April’s speaker was Mark Bachmann from Glenelg Nature Trust. He spoke on the The Hydrological Restoration of Glenshera Swamp, Stipiturus Conservation Park.

At time of settlement swamps were common on the Fleurieu Peninsula but now they have almost all but disappeared. This has come about because of the clearing of land for farming beginning in the 1940s. There are now very few swamps left in the area. As a result in this region, the swamp orchids potentially face extinction.

BUT Mark’s talk was a good news story. In April, the Glenelg Nature Trust with the help of the Conservation Volunteers Australia (a Green Army program) began the work of reinstating the original creek by the judicious placing of regulating structures along the principal drain.

The good news is that the water returned as they were building the structures.

It was also a good news story because of the cooperation of different groups including a local land owner who was willing to have some of their land returned to swamp and no longer be available for their horses to graze.

We look forward to seeing the swamp refill and learning how the orchids respond.

Below are some of the orchids found at Stipiturus. Click on the images to go to the three articles documenting the work at Glenshera Swamp.

Thelymitra cyanea
Thelymitra cyanea

Cryptostylis subulata 008
Cryptostylis subulata (Moose Orchid)

Prasophyllum murfettii sm
Prasophyllum murfettii (Denzel’s Leek Orchid)

Spiranthes alticola

At this time of the year there are not many orchids flowering in South Australia but one that is just finishing is Spiranthes alticola. The genus Spiranthes, commonly known as Ladies Tresses, is found throughout Australia, Eurasisa and the Americas.The following description is an extract from South Australia’s Native Orchids 2011 DVD which is available from the Native Orchid Society of South Australi. 

Spiranthes alticola D.L.Jones

Swamp Spiral Orchid

Etymology: The name alticola means high dweller, referring to its distribution in Eastern Australia, in west Victoria and South Australia’s South East.  It also grows near sea level.

Synonyms: Previously included in Neottia australis R. Br., S. sinensis (Pers.) Ames and S. australis R.Br.

 

 

(These two pictures show the variation in colour.)

Description: Leaves 3-5, narrow lanceolate, shiny, erect at the base, to 15 cm long. Flower stem to 45 cm tall, slender, flexible, with several sheathing bracts.  The flowers are numerous in a dense spiral, pink with a white labellum, rarely all white.  Segments are 6-10 mm long, sepals somewhat triangular, petals lanceolate, together forming a short tube, the tips free and recurved, and the lateral sepals divergent.  Labellum with a broad, decurved crisped, pellucid mid-lobe, side-lobes erect small.  The flowers are faintly fragrant.

spiranthes-alticola-leavesrwl-92

(Leaves of Spiranthes alticola)

Flowering: Dec – Jan – Feb.

Similar Species: S. australis, S. sp. Late selfing-white.

Distribution: SL, KIx, SE; NSW, Vic, Tas.

Confined in South Australia to a few high rainfall, near coastal, often mountain locations, southward from the Adelaide Hills in the Southern Lofty region, extinct on Kangaroo Island, (one record only), and South East; also in New South Wales, Victoria and Tasmania.

Habitat: Restricted to peaty bogs and swampy creek-sides, often in locations that are inundated throughout winter; in some areas surviving in paddocks grazed by stock.

Distinguishing Features:  S. australis, which is from the eastern states and is not strictly a swamp plant, has smaller darker pink flowers with a narrow labellum.

  • The two South Australian forms treated here are regarded as distinct species as where they are sympatric they begin flowering at different times and do not intergrade. S. alticola is the more delicate of the two.

Notes:  The best specimens are found on mowed firebreaks adjacent to swamps.  When vegetative reproduction produces two clonal plants next to each other the spiral arrangement of one is often a mirror image of the other.  See Gallery.

Native bee pollinators work the spikes from the bottom upward but as the stigma becomes receptive well after the pollinia have matured this mechanism helps ensure outcrossing.

Plants do well in cultivation if kept moist over summer.

Conservation Status:

Status in Legislation: Not listed nationally, rare in South Australia.

Suggested Status: Rare in South Australia but more common in the Eastern States

 

Names, Names, Names, …

Orchid names are contentious.  The reasons appear to be complex but whatever the reasons the situation exists whereby some orchidologists are naming species that may or may not be accepted by others.  The result is that there are publications using different names for the same species.  And of course, in the midst of it all, are those names that have been accepted for previous species with phrase names or manuscript names.

Whatever the name, it is helpful then to be able to match them up.  Last week’s blog covered South Australian names but in the same week Andrew Brown published on the Western Australian Native Orchid Conservation Study Group Facebook an updated list of WA orchids whereby he has linked them with significant WA Orchid field guide books.

Andrew has kindly given permission for this list to be published.  Other lists are also included and these are available on the NOSSA’s  Orchid eBook page.

It is worth reading Andrew’s introduction in ALIGNMENT of WESTERN AUSTRALIAN DIURIS AND PTEROSTYLIS NAMES.

The object of this exercise is to align the phrase names in these three publications with names published in recent taxonomic papers. Please note that most, but not all, currently recognized (described and undescribed) Western Australian Diuris and Pterostylis are included. There are other taxa that may be considered worthy of recognition but have not been included at this time as we feel further research is required.

In the case of phrase names, these are added and removed for taxa as new information comes to hand and should not be thought of as the final view. Rather, these should be thought of as current thinking that may change in the future. Taxa are only formally recognized as being distinct once their scientific names are published. Even then, later thinking may result in further changes.

Given that phrase names are a work in progress, some may think that we should not be promoting their use and that they should not be included in popular books. However, I think it is worthwhile putting them out to the wider audience so that their distinctiveness can be debated. Having a large group of people looking for (and at) these taxa provides us with a great deal of information and opinion based on firsthand experience in the field, that we may not otherwise have obtained. Then, if and when the taxon is formally described, it will be done on a much more informed basis.

As I am sure you are aware, the naming plants is an evolving process and there will be further changes as new information comes to light.

Andrew Brown

1605 sm PM Caladenia flava
Caladenia flava

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