Monthly photo competition

by

Caladenia plicata – April Winning Photograph

Shane Grave’s winning photograph for April was the spring flowering Caladenia plicata which is endemic to the South West of Western Australia.

Caladenia is a very large genus with over 330 species, 39 of these currently unnamed. In addition, there are 58 named subspecies and varieties. Caladenia plicata would belong under the subgenus Calonema or the segregate genus Arachnorchis which, although not generally recognised by State herbaria is commonly accepted by many amateur enthusiasts. Yet even this subdivision is still large with 192 species. As a result, some authors have created further groups/complexes, for example C. dilatata complex, C. longicauda complex, etc. However, according to Andrew Brown, C. plicata doesn’t seem to fit neatly into any of these categories, although David Jones does include it within the clubbed spider orchids.

Various authors consistently refer to the labellum as being unusual. In Fitzgerald’s formal description (1882) he states that the labellum tip is “recurved so as to become plicate and touch the under surface of the disc”. Plicate means to fold. The labellum tip of many other Arachnorchis species are known to curl under but none fold under in the way that this species does. The sharp fold with the spreading horizontal fringed margins (edges) combined with a central band of tall dense calli (wart-like structures) gives a distinctive shape reminiscence of a crab, hence the common name Crab Lipped Spider Orchid. The effect of this is best seen from a front, rather than a side, view.

The very mobile labellum is sufficient to identify this species, but it is also possible to identify when in bud “due to the prominent short osmophores (clubs) on the sepals”. The sepals narrow halfway along to form thick brown clubs and when the flower is open both the lateral sepals and petals are downswept. This is clearly seen in Shane’s photograph.

Finally, for those interested in pollination, it is pollinated by an undescribed male thynnine wasp of the genus Zeleboria. This has been captured on video https://ars.els-cdn.com/content/image/1-s2.0-S0960982217306310-mmc6.mp4

 

Thank you to Andrew Brown for assisting me with this article.

References:

Brown A, et al, Field Guide to the Orchids of Western Australia 2013

Brown A, personal communication

Caladenia accessed 24 May 2019

https://en.wikipedia.org/wiki/Caladenia

Caladenia plicata Wikipedia accessed 24 May 2019

https://en.wikipedia.org/wiki/Caladenia_plicata

Haiyang Xu et al Complex Sexual Deception in an Orchid Is Achieved by Co-opting Two Independent Biosynthetic Pathways for Pollinator Attraction 2017

https://www.sciencedirect.com/science/article/pii/S0960982217306310

Jones DL, A Complete Guide to Native Orchids of Australia including the Island Territories 2006

Jones DL, et al, Australian Orchid Genera CD-ROM 2008 CSIRO accessed 24 May 2019

https://www.anbg.gov.au/cpbr/cd-keys/orchidkey/html/genera/Arachnorchis.htm

Pelloe, EH, West Australian Orchids 1930

http://gutenberg.net.au/ebooks04/0400681h.html#page50

Orchids of South-West Australia website

http://chookman.id.au/wp_orchids/?page_id=2424

 

 

Advertisements
by

Corunastylis ciliata – 2019 March Winning Photograph

The winning photograph for March 2019, was Corunasylis ciliata (syn Genoplesium ciliatum). As with so many orchids, it has undergone a few name changes. Originally Prasophyllum, then Genoplesium and currently Corunastylis

Although Genoplesium was split into two with only one species remaining in Genoplesium and the others placed into Corunastylis, this split has not been accepted by the everyone. For example, eflora of SA and PlantNET use Genoplesium whilst VicFlora uses Corunastylis.

Whilst researching C. ciliatum I came across images of Prasophyllum spp. being misidentified as Corunastylis spp. and as it was originally described in Prasophyllum it seems appropriate to examine the similarities and differences between the two genera.

In South Australia (SA), the most obvious difference would appear to be size but across the rest of the country some Prasophyllum species potentially can be similar in size to the much smaller Corunastylis, although Corunastylis species are never as large as many of the Prasophyllum species.

Some of the shared features of the two genera are

  • multi-flowered on a single stem
  • single tubular leaf
  • flowers non-resupinate, that is the labellum is above the column and the dorsal sepal is below (the only other non-resupinate flowered orchids in SA are Gastrodia, Caleana, including Paracaleana, and Cryptostylis subulata)
  • Grow as scattered individuals
Prasophyllum Corunastylis
Size Tends to be a larger plant (up to 150cm), but can sometimes be as small as Corunastylis Always a small plant (maximum no more than 90mm)
Leaf Leaf sheaf opens well below the inflorescence (flower head) Leaf sheaf opens at the base of the inflorescence.
Leaf Often withered at flowering Not withered at flowering
Labellum Immobile Mobile
Usually curved backwards (recurved) resulting in an upright appearance of the flower. Not recurved resulting in a more drooping appearance of the flower
Season Mainly spring flowering Mainly autumn flowering

 

References:

Jones DL A Complete Guide to Native Orchids of Australia including the Island Territories 2006

Prasophyllum and Corunastylis descriptions from VicFlora, accessed 1 May 2029

https://vicflora.rbg.vic.gov.au/flora/taxon/bbf0eb5e-fc8d-426b-9cac-58c384474e17

https://vicflora.rbg.vic.gov.au/flora/taxon/91aa3829-ead8-407f-9db7-db2357ddb7e1

Bates R & Weber J Orchids of South Australia 1990

Jones DL, et al, Australian Orchid Genera CD-ROM 2008 CSIRO

 

Thank you to Greg Steenbeeke for reviewing the article.

 

 

by

Thelymitra malvina (Purple Tufted Sun-Orchid)

2019 Winning Photograph Competition

Welcome to our first competition for 2019. For February we had five entries which included Pauline Meyers’ Prasophyllum species from Western Australia, Lindy McCallum’s Glossodia major  and Leptoceras menziesii, Lisa Incoll’s Thelymitra antennifera.

1902 SM Pauley Thelymitra malvina

The winner was Rob Pauley’s photograph from the south east of Thelymitra malvina (Mauve Tufted Sun Orchid) which is found in only a few places in the South East but does occur in Victoria, New South Wales, Queensland, Tasmania and even ‘across the ditch’ in New Zealand where it is considered “an Australian species now established in the North Island”.

According to the Atlas of Living Australia, it is endangered in Victoria, South Australia,  Tasmania; of Least Concern in Queensland and there is no listing for New South Wales.

This species has been included in both the T. nuda and T. pauciflora complex for, as Jeanes has observed, it has characteristics of both complexes such as the smaller flowering forms are self-pollinating, and the larger flowering forms are insect pollinated

Though the common name, Mauve Tufted Sun Orchid, indicates that its most distinctive feature are the purple tufts on the post anther lobe, it is possible to find them with white tufts and there are other species that have purple tufts (eg in SA T. azure and T. occidentalis may have purple tufts but it is obvious from their other features that they are not at all similar to T. malvina).  There are no other closely similar species in South Australia, but on the other hand, in the eastern states, it can be confused with Thelymitra atronitida, so it is worthwhile considering some of the main differences between these two.

Although there are no other closely similar species in SA, in the eastern states it can be confused with Thelymitra atronitida, so it is worthwhile considering the differences

T. malvina T atronitida
Stem 3 sterile bracts 2 sterile bracts
Height 25 – 75 cms 30 – 50 cm
Flowers Slightly larger (but can have smaller flowers) Smaller flowers
Inflorescence 3 – 25 usually loose 2 – 8 ( – 16)
Column Reddish to dark brown with yellow apex Glossy black with yellow apex
Post anther lobe Moplike tuft of pink or mauve (rarely white) trichomes Moplike tuft of white trichomes (hairs)

Across the country, there is some variations of flowering times with New South Wales having the longest flowering time from August to November and South Australia along with Tasmania having the shortest of October and November.

REFERENCES

Bates RJ, 2011 South Australia’s Native Orchids, electronic

Backhouse G, Bush Gems, A Guide to the Wild Orchids of Victoria, Australia, 2016, electronic

VicFlora, https://vicflora.rbg.vic.gov.au/flora/taxon/0de4b1c5-3f1f-43ea-9464-c713a12d5758 Accessed 6 March 2019

VicFlora, https://vicflora.rbg.vic.gov.au/flora/taxon/748b23b6-4779-4a93-89fc-8ec2a8b05a06  Accessed 6 March 2019

Atlas of Living Australia, https://bie.ala.org.au/species/NZOR-4-76548  Accessed 6 March 2019

New Zealand Native Orchids, https://www.nativeorchids.co.nz/Descriptions/Thelymitra_malvina.html Accessed 6 March 2019

Jeanes J, 2013 An overview of the Thelymitra nuda (Orchidaceae) complex in Australia including the description of six new species https://www.rbg.vic.gov.au/documents/MuelleriaVol-31-p3-Jeanes-PDF-Accessibility.pdf Accessed 6 March 2019

Natural Value Atlas, https://www.naturalvaluesatlas.tas.gov.au/downloadattachment?id=14596  Accessed 6 March 2019

by

2018 August Winning Photograph

1808 sm JP Corysanthes incurva Penola CP

This month’s winner was Jenny Pauley’s photograph of a Corybas incurvus (syn Corysanthes incurva).

Before looking specifically at the species, it might well be worthwhile looking at the features that distinguish the Corysanthes (Toothed Helmet Orchid) group from Corybas (Spurred Helmet Orchid). The major difference appears to be in the flowers. The Corybas flower is dominated by the dorsal sepal which hides the labellum whereas with the Corysanthes the dorsal sepal and labellum are equally prominent although sometimes the dorsal sepal may be the less dominant. A less obvious difference occurs in the leaves. Corysanthes leaves have a fine point but this is absent in Corybas. Based on this only Corysanthes (Toothed Helmet Orchid) occurs in South Australia.

C. incurva, as part of the Corysanthes group, is interesting because the flower does not appear flared or toothed. But though the labellum curves in, it does initially start to flare, and it does have fine short teeth. In fact, in the early stages of the flower opening it can be possible to confuse it with the opening bud of C. diemenica. One of the differences between these two species is that the flower of C. incurva sits on the leaf with no clearly visible stem whilst C. diemenica is raised above the leaf with a visible stem.

This image of a typical Corybas from Colin Rowan, retiredaussie.com , helps to see the difference between Corysanthes and Corybas.

https://i1.wp.com/www.retiredaussies.com/ColinsHome%20Page/OrchidsNSW/Corybas/Corybas%20dowlingii%20Red%20Lanterns/Corybas%20dowlingii%20Red%20LanternsP1180804.JPG

This image of C. diemenica (syn Corybas diemenicus) is a good comparison. Note the difference between the stems.

Corybas demenicus

Corybas demenicus

by

2018 July Winning Photograph

1807 sm JF thelymitra azurea

Thelymitra azurea (common name Azure Sun Orchid)

With two sun orchids entered this month it is not surprising that one of them should be the winner which was John Fennell’s Thelymitra azurea a lovely blue flower with hints of pink. The other sun orchid taken by Pauline Meyers was one of the lovely pinks, T. rubra. She also entered a picture of Pyrorchis nigricans with a spider quietly waiting for its next meal! The final entry from Trevor Williams was that of a double headed Diplodium robustum which he found at Spring Gully Conservation Park.

 

by

June 2018 Winning Photograph

1806 sm JB T epipactoides1

 

An advantage of entering a photograph is that it does not need to be in season. This month John Fennell entered an autumn flowering Corunastylis fuscoviride and a late spring/early summer flowering Diuris sulpherea, Robert and Rosalie Lawrence both entered the winter flowering Diplodium robustum and the winning picture, John Badger’s Thelymitra epipactoides is an early spring flowering orchid.

Sun Orchids are another popular winner of the competitions and as there was a comprehensive article written on Thelymitra epipactiodes and as some have asked “what, actually, is a sun orchid?”, it is time to answer the general question about Sun Orchids.

Of all the Australian terrestrial orchids Thelymitra or Sun Orchid is the one that looks the least like an orchid as all the segments – the sepals and petals including the labellum – are very similar in appearance. They mimic the flowers of the Lilliaceae and Goodeniaceae families.

Nevertheless, it is an orchid as evidenced by the column. Columns are a unique feature of orchids. They are the combination of the reproductive organs into one structure. Between the different Thelymitra species, it is the column that is often the main distinguishing feature used in identification. Because, the column is quite detailed and so important in identification, we plan to feature this in future Journals.

Other general features of Thelymitra are single, non-hairy, mainly linear leaf (of course, there are always exceptions) with a single flower stem. Flowers range from being singular to having multiple flowers which come in a range of colours from yellow to pinks to blues. Despite the lack of nectar, most Thelymitra are bee pollinated but there are some that are self-pollinated. The pollinia instead of being yellow are white and it is not unusual to see the white pollen on the self-pollinating flowers.

Reference

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

Jones, D. L., A Complete Guide to Native Orchids of Australia Including the Island Territories. Reed New Holland

Jones, D. L.; Hopely, T; Duffy, S. M.; Richards, K. J.; Clements, M. A and Zhang X, Australian Orchid Genera an information and identification system. Electronic version, 2006, CSIRO

Thelymitra https://en.wikipedia.org/wiki/Thelymitra Accessed 4 July 2018

by

May 2018 Winning Photograph

One never knows what species will be entered each month – this month’s entries included Andrew Primer’s Eriochilus collinus, John Fennell’s Prasophyllum elatum, Marg Paech’s Pterostylis nutans and the winning picture, Pauline Meyer’s Arachnorchis sp. (which has subsequently been identified as Arachnorchis sp.)

 

1805 sm PM Arachnorchis sp

In the last six years there have been over a dozen photo competition articles (the most recent April 2018) written on some aspects related to Spider Orchids. So, with another Spider Orchid winning the competition it is about time to answer the question – What Is A Spider Orchid?

 

Around the world, the common name Spider Orchid has been bestowed upon a number of orchids in different genera. In Australia, they have principally been applied to a large group within the genus Caladenia, a highly diverse cumbersome genus.

Caladenia in the broad sense is distinguished by erect flower stem and single linear, ovate to lanceolate leaf, (both hairy), labellum distinctly different from the other segments, generally fringed, curved and decorative calli. But within this genus it has been recognised for a long time that there are several distinct but varied groups, which has been reflected in the common names – Dragon, Pink Fingers, Hare, Spider, Wispy Spider, etc.

Consequently in 2001, several segregate genera were published including Arachnorchis for the common named Spider Orchids. This was not widely accepted, as reflected by the Herbaria of Australia. Indeed the original authors are no longer using the segregate names.

Yet despite all that, the segregate names have proved to be very practical for fieldwork. By using the segregate name when species is unknown, extra information is communicated. This was the case with Pauline’s picture. Yes she photographed a Caladenia but which one? It was an Arachnorchis species.

With that in mind, it is time to consider the features that make up a Spider Orchid or Arachnorchis.

In following through a dichotomous key Arachnorchis is immediately separated out from the rest of the Caladenia by the presence of two yellow waxy glands at the base of the column. As this is not the immediate feature seen, the following chart comparing it with the very similar looking Joneseopsis should assist with recognising some of the main distinguishing features.

  SPIDER ORCHIDS
(ARACHNORCHIS)		 WISPY SPIDER OR DADDY LONG LEGS
(JONESIOPSIS)
Leaf Sparse to densely hairy
Narrow to broad lanceolate
Red base		 Sparsely hairy
Slender
Red base
Stem Wiry densely hairy Hairy wiry
Flower    
Dorsal sepal Erect Erect
Tepals

(Petals & Sepals)

 Long & slender with long slender glandular tails or thickened short to long clubs*

Petals and sepals similar size

 Narrow, end in very long thin threadlike glandular tails*
Labellum Trilobed
obliquely erect lateral lobes
Midlobe often differently coloured to the base		 Small indistinctly lobed

Narrow
  Hinged Hinged
Apex Rolled under at the apex Rolls under*
Margins Fringed with short to long teeth* Short, blunt teeth to smooth
Calli Vary from short rounded crowded to long curved and widely spaced Short blunt congested lamina calli*
  2 or more rows 2 rows*
Basal Gland 2 yellow at  base of the column None
Growth Habit Loose groups* Clumping

 

*Exceptions in all these descriptions

1805 PM Arachnorchis sp Labelled wm

Labelled Features of a Spider Orchid

Reference

Backhouse, G, (2018) Spider Orchids: The Genus Caladenia and Its Relatives in Australia ISBN: 978-0-9946489 Electronic version

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

Jones, D. L., A Complete Guide to Native Orchids of Australia Including the Island Territories. Reed New Holland

Jones, D. L.; Hopely, T; Duffy, S. M.; Richards, K. J.; Clements, M. A and Zhang X, Australian Orchid Genera an information and identification system. Electronic version, 2006, CSIRO

 

by

April 2018 Winning Photograph

1804 sm JF oligochaetochilus excelsus koongawa 2

Oligochaetochilus excelsus, an impressive name for the winning photo, taken by John Fennell. It was originally formally described and named Pterostylis excelsa by Mark Clement in 1986 from a specimen cultivated from a tuber taken from Eyre Peninsula. This was subsequently published in the fourth edition of Black’s Flora of South Australia. In the early 2000s, the genus Pterostylis was split into several different genera of which Oligochaetochilus was one.

Although not everyone accepted this change, it is helpful for understanding the characteristics of this group. They are found only in Australia and are primarily a semi-arid inland group, sometimes the only orchids to occur in a locality.

Bob Bates has documented some of the drought tolerant and drought avoidance features found in this group as follows.

Drought tolerance:

  • Large moisture-storing tubers, shallowly buried to take advantage of light rain.
  • Waxy leaves pressed flat to the soil thus avoiding water loss.
  • Fast growth, some species are able to flower on just two good rainfalls.
  • Leaves senesce (die off) before or soon after flowering begins; moisture and food from the leaves is then stored in the tuber and scape. Leaves are able to absorb moisture from dew.
  • Leaves also contain an anti-freeze and can tolerate black frosts.
  • Just one month after rain a replacement storage tuber is produced as large as the old.

Drought avoidance:

  • Plants favour damper microhabitats, growing at the base of larger rocks and in seepage zones or on the cooler damper south side of bushes.
  • Tubers of desert species do not usually germinate in drought years.
  • Leaf senesces (dies off) before hot weather meaning plants avoid moisture loss during flowering.
  • Plants cease respiration in long dry periods and resume after rain even up to three months later, staying green even in bone dry soil.
  • Leaves are pressed to the soil.

References:

https://en.wikipedia.org/wiki/Pterostylis accessed 10 May 2018

Jessop, J. P. and Toelken, H. R. (eds) (1986). Flora of South Australia. 4th ed. Adelaide: Government Printers Adelaide.

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

by

March 2018 Winning Photograph

1803 A4 sm JF Arachnorchis formosa

Four very different species were entered this month. Ricky Egel’s autumn flowering Coryunastylis fuscoviridis (see February Journal for name usage), Rosalie Lawrence’s winter flowering Diplodium bryophilum and John Fennell’s spring flowering Stegostyla cucullata and Arachnorchis formosa.

It was no surprise that John’s A. formosa (syn. Caladenia formosa) was the winning photograph. Words such as stunning, spectacular, wonderful and attractive are used in the description of this rare orchid and is reflected in its common names – Scarlet Spider Orchid, Elegant Red Spider Orchid, Elegant Spider Orchid and Blood-red Spider Orchid. It is truly a stunning red flower with its drooping petals and sepals (tepals).

A. formosa is part of the large patersonii alliance which is characterised by white to reddish flowers with (mainly) drooping tepals ending in long, slender (sometimes thickened) sparsely to densely glandular (hairy) tails, labellum with short to long marginal teeth. The features that separate A. formosa from others in the complex are the large (~60 mm across) deep red flowers with long (~80mm) tapering, drooping tepals. Similar species to A. formosa is the smaller once common but now extremely rare Caladenia ‘Fleurieu Peninsula’ In Victoria there are some other similar species.

A. formosa is confined mainly to the South East and into south western Victoria.

References:

Backhouse, G., (2011). Spider-orchids – the Genus Caladenia and its Relatives in Australia, Melbourne, Electronic version.

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

by

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