The following article is from the Native Orchid Society of South Australia Journal Volume 44 No 7, author Rosalie Lawrence.
Over the years there have been many orchid name changes (particularly at genus level), some quite drastic, some multiple times and for many there can be a reversion back. Yes, this creates confusion but there are times when some of these name changes, known as segregates (both at species and genus level) can be useful.
A case in point, is Lindsay Ames’ winning photograph (June) – Caladenia carnea synonym Petalochilus carneus. Petalochilus was proposed as a genus in 2001 by DL Jones, MA Clements, et al. It was one of many proposed genera changes. Many discussion papers followed but in 2015 after further taxonomic and DNA work, Mark Clements et al published a paper that “points to Lindley’s 1840 interpretation of Caladenia (…..) as being the most accurate reflection of the group.” Hence the discontinued use of Petalochilus and the other segregate genera.
So, it currently belongs with Caladenia, a large genus with over 350 species (mainly in Australia). It is a genus with great morphological (visual) diversity – compare Caladenia tentaculata with C. cucullata or C. flava. But Caladenia
subgenera Caladenia (synonym Petalochilus*), as a much smaller segregate genus allows us to visualize a specific group within the Caladenia genus.
Caladenia sens. lat. are characterised by single hairy leaf, lacking lobes or serrations; hairy stem; showy flowers with similar sepals & petals. The labellum is highly modified consisting of three lobes with calli on the middle lobe.
Petalochilus is further characterised by small (1 – 5 cm) pink to white flowers,
short broad forward projecting tepals; erect to slightly incurved dorsal sepal,
distinct trilobe labellum, hinged, with calli and red transverse bars, column
green to pink with red to purple bars.
Yet within Petalochilus itself there can be further groupings of which P carneus is most likely the main one. This consists of at least 8 species – P carneus (C carnea), P catenatus (C catenata), P coactilis (C coactilis), P fuscatus (C fuscata), P ornatus (C ornata), P prolatus (C prolata) , P. vulgaris (C vulgaris) and P xantholeucus (C xantholeuca). When a specimen cannot be identified to species level, it may be helpful to refer to it as a complex.
This is where comes the fun of trying to identify the specific species in the field (or for that matter from a photograph). To help myself understand, I often produce comparison charts based on descriptions found in the literature. The chart comparing the eight species is available as a pdf.
*Throughout the article the synonym Petalochilus is used for Caladenia subgenera Caladenia to make a clear distinction from Caladenia sens lat. It needs
to be noted C carnea is considered the type specimen for Caladenia so with any splits, it will remain in Caladenia.
Backhouse G et al,Bush Gems: a guide to the Wild Orchids of Victoria 2016
Bates R B South Australia’s Native Orchids 2011
Clements MA, et al, Caladenia Revisited: Results of Molecular Phylogenetic Analyses of Caladeniinae Plastid and Nuclear Loci 2015
Jones DJ, A Complete Guide to Australian Orchids including it Territories and Islands 2006
https://en.wikipedia.org/wiki/Caladenia Accessed 3 August 2020
https://www.pacificbulbsociety.org/pbswiki/index.php/Petalochilus Accessed 3 August 2020
Thank you to Andrew Brown for reviewing this article.
The following article, March Winning Photograph, is from Volume 44 no 4, May 2020 Native Orchid Society of South Australia Journal.
Pauline Myers’ Arachnorchis cardiochila was the winning picture. Synonyms for Arachnorchis cardiochila are Caladenia cardiochila, Phlebochilus cardiochilus and Caladenia tessellata. Common names include Heart Lipped Spider Orchid, Thick Lipped Spider Orchid, Fleshy Lipped Caladenia.
This species was named in 1886 by Professor Tate who presented it at the Royal Society of South australia at the October meeting. He did the original drawing.
The type specimen was collected at Golden Grove on October 2 1886 but it had also been collected much earlier (1865) at Barraba Scrub which is in the region of Mallalla.
Its fate in both these areas has not been good; it is extinct in Golden Grove and critically endangered in the region containing Barabba Scrub. Although, it is considered to be a reasonably common orchid throughout its range in South Australia, Victoria and Southern New South Wales, there are areas of concern as seen the Seedbank of South Australia map below.
It should be noted that though Caladenia tessallata is listed as a synonym that this was used incorrectly, as C. tessallata is a separate but similar species found in the eastern states. Its main difference from C. cardiochila is that the edge of the labellum (lip) is toothed, not smooth as seen in Pauline’s photo.
In 2011, Robert Lawrence wrote a book titled Start with the Leaves, a beginners guide to orchids and lillies of the Adelaide Hills. Bob Bates, editor of South Australia’s Native Orchid 2011, suggested that the next title should be End with the Pods. Well another field guide has not been written but following Bob’s suggestion, it might be interesting to see how far one can go with orchid identification based upon the pods, or finished seed capsules.
As most of the orchids for the Adelaide Hills and Fleurieu Peninsula have finished, it might be worth a look at some capsules found this year and see how far we can go with identification.
Here is the first one:
These pictures were taken on a mobile phone on the 30th November, 2019 on the Fleurieu Peninsula. There were several plants with single pods scattered across the park. The stems were reasonably tall (est 30cm) and surprisingly easy to spot.
The habitat is open forest consisting of Eucalyptus leucoxylon (Blue Gum), E. baxteri (Brown Stringybark) and E. fasciculosa (Pink Gum).
Is there enough information to identify this plant to species level?
Comment on what you think it is and why.
The following article has been adapted from the 2019 July Winning Photograph
The July competition resulted in a draw. This article will concentrate upon only one of the winner’s – Lisa Incoll’s photograph of a Diplodium sp. found in the Southern Lofty Ranges.
Sometimes images are sent through unnamed or with only the genus named as in the case of Lisa’s picture. Unfortunately, it is not always possible to determine the identity from only one photograph beyond the genus level. In this case it can be seen that it is a Pterostylis but since the introduction of a segregate genera it is possible to narrow it down further to Diplodium sp.
Since there are two main Diplodium found in the Adelaide Hills (D. robustum and D. sp Adelaide Hills), I thought it would be a good opportunity to compare these two species.
The phrase name D. sp Adelaide Hills is used to distinguish it from D. alatum (syn. Pterostylis alata) which is considered to be endemic to Tasmania. The mainland species P. striata was previously known as P. alata. The eFlora-SA, the Adelaide Herbarium online key and census of the SA Flora has D. sp Adelaide Hills listed as P. alata (syn D. alatum).
D. sp Adelaide Hills and D. robustum share many similar feeatures. In the dichotomous fey found on the eFlora-SA, the separation between the two is primarily based upon size. D. sp Adleaide Hills is generally a taller-stemmed plant with a smaller flower and smaller, more slender cauline leaves. D. robustum is mainly a larger flower on a shorter stem. However there is an overlap between D. robustum and small specimens of D. sp Adleaide Hills which can make determination of species difficult.
Based upon the descriptions and the key from eFlora-SA, Orchids of South Australia (1990) and South Australian Native Orchids (2011), the following table shows the similaritites and differences between the two species. For completeness, shared features (highlighted in bold) are also included.
(syn. Pterostylis robusta)
|Diplodium sp Adelaide Hills|
(syn. D. alatum, P. alata)
|Plant Height||5-20cm tall (usually less than 10cm tall); robust stem||8-25 cm tall; slender stem|
|Leaves||6 – 7 ovate or elliptic-ovate (ie range from oval to egg-shaped) leaves in rosettes on long petioles||3 – 8 ovate leaves in small rosettes on long petioles|
|Flowering Plants||No rosettes or basal leaves||No rosettes or basal leaves|
|Cauline Leaves||Alternating leaves clasping the base & increasing in size from the base upwards. Acuminate (long drawn out point)||Alternating leaves clasping the base & increasing in size from the base upwards. Acuminate|
|Broad (up to 8mm wide) lanceolate serrulate (tiny teeth) cauline leaves more than 3cm long||Slender lanceolate, cauline leaves less than 3cm long|
|Blooms can last up to 8 weeks in sheltered places||Delicate flowers can soon collapse with strong drying winds|
|Inflorescence||Singular flower||Singular flower|
|Colour||Bright green & white with deeper green, longitudinal stripes||Pale-green or white with darker striations|
|Galea||Erect; bulbous near the base||Erect; bulbous near the base|
|Length 25 – 45 mm; diameter more than 20 mm; gradually curved forward at the apex||Length 20 – 25 mm long; Diameter less than 18 mm; gradually incurved|
|Dorsal Sepal||Ends in a long fine point to 5 mm long||Apex blunt; ends in a short fine point|
|Petals||Blunt||Blunt or acute|
|Lateral Sepals||Erect; conjoined basally; distally, the tips produced into long filiform erect points, embracing the galea & greatly exceeding it||Erect; conjoined basally; distally, the tips produced into long filiform erect points, embracing the galea & greatly exceeding it|
|Sinus (region where lateral sepals separate)||Flat, with a wide, shallow central v-notch; protruding in a shallow curve whenviewed from the side||Narrow sinus, with a notch in the middle; not bulging|
|Labellum||Movable claw; nearly straight||Movable claw; nearly straight|
|Erect potition||Recaches height of the column||Slightly exceeding the height of the column|
|Column||Column erect||Column erect|
|Habitat||Forms small to extensive colonies||Forms small to extensive colonies|
|in rocky places; forest or scrublands||in rocky or shady locations; forest or forest heathlands|
|Regions||Mt Lofty Ranges||Mt Lofty Ranges|
|Flinders Ranges; Eyre Peninsula; Yorke Pensinsula; Upper South East||Kangaroo Island; South East; possibly Eyre Peninsula|
|Rainfall area||Greater than 250 mm||Greater than 600 mm|
|Flowering Time||May – September||May – July|
Of course, as these two hybridise, that will complicate things, Hybrids will have characteristics of both parents but, with hybrid vigour; and vigour is one of the separating features between the two!
http://flora.sa.gov.au/cgi-bin/speciesfacts_display.cgi?genus=Pterostylis&species=robusta Accessed 6 September 2019
http://flora.sa.gov.au/cgi-bin/speciesfacts_display.cgi?genus=Pterostylis&species=alata Accessed 6 September 2019
Bates RJ, 2011 South Australia’s Native Orchids, electronic
Bates RJ Weber JZ, 1990, Orchids of South Australia,
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
|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|
|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|
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
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.
This article is a completion of the Thelymitra Column article which appeared in the NOSSA Journal, Volume 42 No 8 September 2018. Click here for Part One.
The first part looked at the features and terms used by botanists to describe various parts of the column, a major identification feature of the sun orchids.
And as previously stated we cannot physically dissect an individual flower, but we can make use of photographs to spot the various features.
The diagram below is that of T. nuda (based on the taxonomy of 1984) column whilst the photographs are that of T. glaucophylla column (as T. glaucophylla is one of the T. nuda complex). The column of these two are similar.
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.
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.
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
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 …
This week’s blog is from the Journal of the Native Orchid Society of South Australia, Volume 42 No 8. Leo Davis has been doing a series of articles aimed at helping members learn how to identify the orchids.
This article is about Plumatichilos, one of the segregate genera of Pterostylis. It has an unique labellum which sets it apart from the other Greenhoods. Leo wrote this article soon after David Jones named them in the Australian Orchid Review. Will these names be accepted or not is a matter of waiting and seeing but it should be noted that they have been in manuscript form for many years. At the time of writing, they are not in the South Australian eflora.
Both the species discussed in Leo’s articles are from the Plumatiochilos plumosum complex or group.
Plumatichilos sp. Mallee Bearded Greenhood =Plumatichilos multisignatus
Plumatichilos sp. Woodland Bearded Greenhood = P. foliaceus
Unless otherwise noted, all images are Leo Davis.
Back in 1990 Bates & Weber placed all greenhood orchids in genus Pterostylis(1. pp118-143) where some of you and all Australian State Herbaria and certainly Janes & Duretto (3. pp260-269) would have them still be. In 2001 Szlachetko erected the genus Plumatichilos. In his Guide(4. pp286-339), Jones divided the greenhoods into 16 separate genera, these in two groups, each of eight genera. One group all have the lateral sepals directed downwards (including Bunochilus and Urochilus) and the other eight all have them directed upwards (deflexed, as in Diplodium and Pterostylis). Even those of you who reject the splitting and creation of the extra genera will concede that those placed in Plumatichilos, which have downward directed and partly fused lateral sepals (forming a synsepalum), are strikingly different in appearance to any other Pterostylis species. The most obvious distinguishing features are the unique labellum and the two openings to the galea.
I had known just two species of Plumatichilos, both of which were undescribed. I could recognise and distinguish them essentially because they grew in very different habitats and locations. I used Bates’ tag names, Mallee Bearded Greenhood (Plumatichilos sp. Mallee Bearded Greenhood) (3. pp913-4) and Woodland Plumed or Bearded Greenhood (Plumatichilos sp. Woodland Bearded Greenhood)(1. pp915-916). In recent weeks both (along with two other South Australian species) have been formally described. They are now, respectively, Plumatichilos multisignatus(5. pp33-35) (Fig. 1) and P. foliaceus(5. pp30-32) (Fig. 2). But, to a large extent, I still identify them more by the locations in which I find them than, to my eye, clearly discernable physical features.
|Fig. 1. Plumatichilos multisignatus. Monarto. Sept 10, 2012.||Fig 2. Plumatichilos foliaceus. Para Wirra. Sept 11, 2013.|
I had no idea what ‘barrier trichomes’ were but I saw that Jones listed them as the last of 13 dot pointed characters of genus Plumatichilos(5. p26). Trichome simply means a hair growing from a plant epidermis. They can be unicellar or multicellular and branched or unbranched. The ‘barrier’ refers to its capacity to block and direct a pollinating insect to an exit path that puts it in the right posture to transfer a pollinium to the stigma (sticky receptive female part of flower).
|Janes & Duretto, who reject the splitting of genus Pterostylis, divide it into two subgenera using the absence (subgenus Pterostylis) or the presence (subgenus Oligochaetochilus) of barrier trichomes on the column wings(3. pp262). They place what I call Plumatichilos in the section V, Catochilus, of subgenus 2 Oligochaetochilus(3. pp266), and, yes, I see your eyes glaze over. To them the Adelaide Hills ‘plum’ would be Pterostylis, subg. 2 Oligochaetochilus, Sec. V. Catochilus, species foliaceus. Learning what ‘barrier trichomes’ are had me go back searching my photo library and I found images of the barrier trichomes in Bunochilus flowers that I had not previously spotted. I have used and annotated a detail sent to me by June Niejalke. (see Fig. 3).
Fig. 3. Bunochilus prasinus. Sherlock (Type location for the species). Photo by June Niejalke.
As with all ‘true’ Pterostylis, the dorsal sepal and the two lateral petals, of the upside down flowers, are formed into a galea or cap (Fig. 1). They are fused so closely that it can be hard to discern the join between the sepal and the comparatively small petals, especially in some less clearly striped flowers. (Figs. 1 & 2).
|The typical Pterostylis galea has a single opening but in Plumatichilos there are two, a lower one, from which the uniquely formed labellum protrudes (and through which the pollinating male gnats enter) and an upper one (through which the pollinators exit) (4. p335), guided by the barrier trichomes (Fig. 4). Through this upper opening you can observe the top of the column, including parts of it, the pollinia, the barrier trichomes, column arms and sometimes the stigma. Two crossed filaments, in front to the pollinia, are column arms.
Fig. 4. Plumatichilos foliaceus. Scott Creek C.P. Sept 2015.
|The labellum (the modified third petal) (Figs 1, 2 & 5) is unlike that of any other Pterostylis sp. It has a slightly flattened filament having a reddish-brown apical knob and two or three types of hairs along its length. Jones describes the labellum of P. foliaceus as having three types of hairs(5. p30). You may be able to see the short white ones (1 mm) at the base of the labellum in Fig. 5. The longer (5-7 mm) yellow ones along the most of the length of the labellum are easy to see. I am not sure that I can distinguish the shorter proximal (near point of attachment) yellow ones (1.5 mm). In P. multisignatus Jones describes just two types of labellum hairs(5. p33) with the white basal ones absent, and two sorts yellow hairs, proximal ones to 1.2 mm and longer ones 5-8 mm. To my eye, this character, two or three types of labellum hairs, is the only objective, rather than subjective , distinguishing feature between the two species that I regularly observe.
Fig. 5. Plumatichilos foliaceus. Scott Creek C.P. Sept 26, 2015.
In Fig. 5, I think that you can see that the hairs arise, in two parallel rows, not paired, from the sides of the flattened shaft of the labellum filament.
|Fig. 6. Plumatichilos foliaceus in early bud. Scott Creek C.P. August 29, 2018.
Another generic character is ‘leaves sessile (no stems), ascending to erect, often with whitish or yellowish interveinal areas.’ (5. p26) You may need to look very closely, in Fig. 6, to see these ‘windows’, mainly at the bases of the stemless leaves.
- Bates, R.J (2011). South Australian Native Orchids, DVD Issued by the Subediting Committee (NOSSA) on behalf of the
Native Orchid Society of South Australia Incorporated.
2. Bates, R.J. & Weber. J.Z (1990). Orchids of South Australia, A. B. Caudell, Government Printer, South Australia.
- Janes, J.K. & Duretto, M.F. (2010), A new classification for subtribe Pterostylidinae (Orchidaceae), reaffirming
Pterostylis in the broad sense. Australian Systematic Botany, 23, 260–269.
- Jones, D.L. (2006), A Complete Guide to the Native Orchids of Australia, Reed New Holland, Australia.
5. Jones, D.L. (2018), Six new species of Plumatichilos (Orchidaceae: Pterostylidinae) fromSouth-eastern Australia and a
new species from New Zealand, Australian Orchid Review 83(4): 26-44.