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.
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.
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.
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. 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 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 yellowishinterveinal 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.
Other articles about Plumatochilos can be found here and here.
This month’s winner was Jenny Pauley’s photograph of a Corybasincurvus (syn Corysanthesincurva).
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.
This image of C. diemenica (syn Corybas diemenicus) is a good comparison. Note the difference between the stems.
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.
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
The Native Orchid Society of South Australia (NOSSA) is affiliated with the national body of native orchid society, Australian Native Orchid Society (ANOS). NOSSA regularly sends reports of its to ANOS. This year’s report covered four years of the society’s activities and is reproduced here to give readers an idea of the many things that we do. This report was produced by Robert Lawrence (currently Vice President).
NOSSA REPORT 2012 to 2016
I believe that the last annual report from the Native Orchid Society of South Australia was in 2011 when we were just commencing a three-year plan with the establishment of a series of subcommittees. All of the committees have since ceased to exist, but not without significant accomplishments.
The Website Subcommittee had established a website, but a Webmaster has since been appointed. The website now uses WordPress and is maintained so that its management could easily be transferred to another person. The website provides a weekly educational post about Australian orchids. It has also provided a point of contact from those outside of the Society. It is linked to a Facebook page that increases the profile of NOSSA among those interested in orchids throughout Australia and beyond.
The Education Subcommittee had established a picture competition at the monthly general meetings. There is still only a small number of contributors, but many excellent pictures are shared. The winning picture from each meeting is used as a basis of one of the weekly posts on the website.
The Education Subcommittee had a vision to produce a brochure of 20 common orchids of the Adelaide region for free distribution to the general public. The NRM (Natural Resources Management) Education ran with the idea and produced a poster of Common native orchids of the Adelaide Hills. This provided brief, but comprehensive, profiles of 29 native orchids and the weedy species. This has been printed as a double-sided poster and is available from the website of Natural Resources Adelaide and Mt Lofty Ranges. NOSSA members worked with NRM staff on the details of the poster and NOSSA members contributed many of the photographs. This poster was completed and launched in April 2015.
NOSSA also provided monetary assistance as a loan with the publication of the field guide entitled, Start with the leaves. A field guide to common orchids and lilies of the Adelaide Hills. This guide covered 50 orchid species as well as native lilies and some weeds in the Iridaceae family that are sometimes mistaken as orchids. The contribution of $8,000 was recovered only 8 months after publication.
The Disc Publication Sub-editing Subcommittee saw the publication of South Australia’s Native Orchids on DVD discs in time for the Spring Show in September 2011. Both the DVD and the book were published in time for the Spring Show in September 2011. Both continue to sell.
A new subcommittee has been established in February 2016 to oversee the publication of a field guide, expected to be called Wild Orchids of South Australia. It is proving to be a challenge to be brief enough to reduce the information to a size suitable for a field guide. (Editor’s note: it has since been decided to defer this until after the development of the interactive website, see below.)
NOSSA members have being working since 2014 to establish an interactive website and database modelled on the Go Botany website run by the New England Wild Flower Society in the USA. This was supported by a grant from the Australian Orchid Foundation. The project is called Wild Orchid Watch. It is hoped to produce an interactive, web-based orchid identification tool. Recording sightings through such means as apps on mobile telephones are also being investigated.
In 2014 NOSSA made a donation to help establish the Orchid Conservation Program. This was led by Dr Noushka Reiter. Once established, staff in the Department for Environment, Water and Natural Resources began to organise a trial with four threatened orchid species from South Australia. Noushka visited South Australia during 2015 and collected samples from each of these species and isolated fungi from these. Seed was also collected and work on propagation commenced in 2015. During 2016 NOSSA sponsored the propagation of one of the four species through the Adelaide Botanic Gardens. Caladenia gladiolata, an endemic species, was selected.
Paul Beltrame, a secondary teacher at Kildare College, contacted and joined NOSSA during 2014 with the interest in getting girls at this school involved in the propagation of native orchids. A program was organised modelled in the Orchids in Schools program run by the Orchid Club of South Australia with Les Nesbitt’s involvement.
A delegation from Kildare College, ably assisted by their enthusiastic laboratory assistant Nenah McKenzie, visited Noushka in Melbourne and learnt the technique for separating and growing fungi. They have since separated fungi from two of our more common greenhood species and supplied this for seed kits that were made available to members as a trial at the start of the 2016 growing season.
The trial of seed kits was done for Pterostylis nana and Pterostylis sanguinea. A trial was conducted in this growing season of seed kits for members. Kits included a pot, growing media, seed, fungus, mulch and instructions. There seems to be limited success with the current round, but improvements are planned from the lessons learnt. One particular growing mix proved successful with a small number of seedlings appearing. The contribution of the Orchids in Schools program at Kildare College has been necessary for the isolation and production of fungi for the kits.
In October 2012 Cathy Houston and Robert Lawrence collected seed of Pterostylis arenicola from the only population on the Adelaide plains after monitoring in September indicated a good year for seed production. The seed was germinated in 2013 and was deflasked at a working bee at the Adelaide Botanic Gardens in early August 2016. The students from the Orchids in Schools program at Kildare College participated. Latest reports are that 40 plants look like surviving. These will be used for seed production and for reintroduction.
In 2012 NOSSA was asked to care for and propagate rescued Diuris behrii plants from Hillgrove Resources Mining Lease near Kanmantoo in the Mt. Lofty Ranges. The plan was to maintain the rescued orchid clones in cultivation for several years and to produce additional plants for reintroduction within the mining lease area each Autumn. A comprehensive recording and auditing system has been put in place to track each clone and any seed/daughter tubers/plants. By August 2015 there were 609 plants with 75 original mother plants. There were 95 daughter plants returned to the site for revegetation in each of the years 2014, 2015 and 2016, a total of 285 plants.
Funding from Hillgrove Resources has assisted NOSSA financially and has made it possible to consider funding conservation work. NOSSA is planning to apply for charity status so that donations can be used for tax deductions. Donations will then be feasible through our website. We are also starting an orchid seed bank. Seed will be available only to members and it is hoped that this will increase our membership. There is a demand for Australian orchids overseas and it is hoped that this will become a means for raising funds for conservation. Other means of fund-raising such as sausage sizzles and selling kits for craftwork are also being considered.
NOSSA members still continue to be involved in surveys and monitoring threatened orchids. Members have been involved in the planning of monitoring.
The management committee of NOSSA is currently working on a revision to the Rules of Association. In the current version there is a two-year limit on the term of the President of two years. In the first 16 years from 1977 there were there were eight different presidents before one had a second term. Bill Dear was president in alternate terms until he retired and moved to Western Australia in 2012. Robert Lawrence was elected president in March 2014, but for the first time in 2016 there were no nominations for president and he was nominated to the role of vice president with no other nominations. The management committee has appointed a subcommittee to review the Rules in relation to the terms of the president. Another change planned is change from having monthly general meetings to having less formal monthly meetings at which no decisions are made or minutes kept. All resolutions will require calling a formal special meeting. This idea is adapted from the approach used by ANOS Victoria.
Over the last two years NOSSA has asked new and renewing members to complete a survey of their interests. This has proved to be an effective way of getting information on the interests of our members with 79 responses, this being about half of the number of memberships. This is an overall summary of the results ranked according to number of responses:
Area of interest
General Orchid Knowledge
At its establishment NOSSA was primarily a Society of orchid growers. These figures reflect a decline in interest in growing orchids. The figures are somewhat surprising in that the numbers interested in growing orchids are much larger than the number of growers. Presumably some of these are interested in learning with a view to getting involved with growing later. At least we hope this is the case.
We are certainly noticing a decline both in our numbers of growers and in members involved in surveys due to age and health.
The greatest number expressed an interest in general knowledge and we are relying on the Journal and the Website help to keep people interested and informed. Next was field trips, but we haven’t had that many that have attended field trips in in the last few years. Only 11 of those who expressed an interested in field trips are not interested in photography, the next item of interest, and only 10 people interested in photography were not interested in field trips. Not many of these share their photographs at monthly meetings. We are hoping to get members to make their photographs available for the identification guides.
It is pleasing that 58% are interested in conservation, thus supporting the efforts of our Conservation Officer.
Growing terrestrial orchids was next on the list; we hope that the tuber bank and the NOSSA Seed Kits are meeting the demand from members. Twenty-two of the 41 interested in growing orchids are interested in growing both terrestrial and epiphytic orchids. Only 8 of the respondents are bringing plants to meetings and a couple of others have not completed the survey. Of those interested in growing terrestrial orchids, one is a former grower and another is interested in growing them in situ at revegetation sites.
Thirty members expressed an interest in doing orchid surveys and three of these are interested in participating in the future, presumably when more time is available.
Citizen science is a new concept to many and came last in our list of interests. One who did not indicate an interest said he was monitoring orchids at a particular site; this has been taken as an interest. Surveys are certainly one form of citizen science and only 2 of those who indicated an interest in citizen science did not indicate an interest in being involved in surveys now or in the future. Thirteen of the 30 interested in surveys did not express an interest in citizen science. If these were included, interest in citizen science would be 43%.
Only seven members indicated an interest in all of the categories and one of these wants to keep in touch with the club and with old friends.
The Annual Spring Show in September 2015 was a particular success, largely due to the efforts of one our new members in promoting the show through local media and by other means. We also benefited from the donation of collections of growers who had decided not to continue with their collections.
NOSSA has continued to maintain a tuber bank that is available for members. A small number of our members are also members of ANOS Victoria, and have obtained tubers from their collection. This is hopefully contributing to the variety of terrestrial orchids grown by our members.
Working bees continued to be conducted in association with the Threatened Plant Action Group at Belair National Park for improving habitat for the nationally endangered Pterostylis cucullata (Leafy Greenhood), at Grange Golf Club to protect and monitor Pterostylis arenicola (Sandhill Greenhood) this being nationally vulnerable and locally endangered and on York Peninsula in conjunction with a local Friends group for the nationally endangered Caladenia intuta.
NOSSA has for many years used Australian Orchid Club (AOC) judges and knowledgeable members, who have all studied the ANOS judging rules, to judge orchids at NOSSA monthly meetings and shows. As the number of judges has fallen in recent years, judging training sessions have had to been discontinued. We wait in anticipation for a proposed ANOS judges correspondence course, as we have for more than 10 years. There are at least three AOC judges interested in the ANOS judging correspondence course. It is disappointing that ANOS Awards are still limited to Queensland, New South Wates and Victoria.
In summary, NOSSA continues to be active in many ways and these activities are working together to support each other.
This month’s entries are an interesting collection as it is probably the first time that all entries are currently in flower. Rosalie Lawrence entered a Pterostylis pedunculata, Ricky Egel (second) Corysanthes despectans, Robert Lawrence (third) Pyrorchis nigricans whilst both Rob Soergel and Claire Chesson (winner) entered Pheladenia deformis. All four are colony forming species.
Both parts of the scientific name for the winning orchid refer to the labellum. Pheladenia meaning false glands which is referring to the calli and deformis meaning departing from the correct shape or mis-shapen.
The labellum plays an important role in pollination; it is the landing platform for the insect. Depending on the process by which the flower is pollinated – or at least attracting the pollinator – this can attempt to mate with the labellum which it has confused for a female of its species (pseudocopulation), or can then feed on the nectar produce. Like many orchids Pheladenia does not produce nectar so the actual attractant for the insect is hard to determine.
The labellum is a distinctive feature of orchids. A modified petal, they are so amazingly varied and complex that botanists often provided detailed descriptions of the features which are present in various combinations, as a means of describing the species. Terms such as lobes, margins, gland/calli, hairs/vestiture/setae, longitudinal ridges, plates, auricles, spurs, papillae etc are used to describe the various features of the labellum.
Some of the features of the labellum of P. deformis are:
It is stiffly attached to the column, unlike Arachnorchis tentaculata which is hinged and freely moving
It is tri-lobed meaning that the labellum shape is divided into three distinct sections.
Unlike Diuris pardina where this feature is easily seen, it is obscured as the outer two lobes are erect and curved in so that it forms a trumpet like appearance with the column.
The margins or edges of the labellum have fine teeth which are slightly curved inward. The margins of Arachnorchis cardiochila are smooth-edged and curve outward from the ‘throat’ of the labellum
It has two types of calli, fleshy, non-secreting glands.
The ones at the base are not as easily seen but they are described as being papillae, e., small, irregular, pimple-like projections or bumps.
The more obvious ones that give the flower its bearded appearance are elongate and without a swollen head, like the bristles on a brush.
In contrast, Thelymitra does not have any type of calli, although it should be noted that calli do play an important role in orchid pollination.
The apex, tip of the labellum, is curved under (recurved to reflexed)
To see some of the variety of labella, Orchids of South Australia (Bates and Weber, 1990) have several drawings detailing the differences on pages 35 to 38, 81, 97, 104 to 106, 114, 119 to 124.
So why spend time looking at details of labella?
It is not important for identifying Pheladenia deformis but it can be a distinguishing feature for other species, for example, the lateral lobes of Diuris maculata are much narrower than D. pardina (Jones, in Harden (ed.) 1993); or the shape of the callus cluster on Chiloglottis which alludes to the species.
Bates, R.J & Weber, J.Z. (1990) Orchids of South Australia, Government Printer, Adelaide
Brown, A., et al, (2013) Field Guide to the Orchids of Western Australia. Perth, WA: Simon Neville Publications
Jones DL (1993). Diuris in Harden GJ Flora of New South Wales, Volume 4. University of NSW Press, Sydney.
Jones, D L et al, (2006) Australian Orchid Genera, an information and orchid identification system, interactive CD-ROM
Thank you to Greg Steenbeeke for assistance with this article.
In the past week there has been some Facebook conversation on the identification of some Thelymitra (Sun Orchids) here in South Australia. Sun Orchids can be problematic particularly when there is only one photograph. If the photograph has a clear view of a diagnostic feature, then identification becomes simpler but there are many species for which careful observations are necessary to determine the correct one. This is important when considering some of the complexes, eg T. nuda and T. pauciflora which have several similar species. Colour is not always helpful as there can be either variation in colour or no colour at all. Further complicating identification is that Sun Orchids readily hybridise, far too easily sometimes!
When Robert Lawrence wrote his book, Start With the Leaves, he realised the difficulty in identifying some orchids, so he included a checklist of observations. The checklist is extensive but was developed to be used with the electronic version of South Australia’s Native Orchids by RJ Bates which covered all the known South Australian orchids in 2011.
To assist in orchid identification, take as many photographs as possible, showing different parts of the plant and habitat from as many different angles. But remember, photograph the typical plants.
At the bottom of the post is a picture showing the parts of the flower.
The following extract is from pages 185 – 187
Thelymitra species (Sun Orchids)
Describe the habitat where the plants are found
Is the species confined to swamps or very moist sites?
Was the site burnt in the last year or two? (Find out when if possible)
Are the plants restricted to a particular habitat or is there a range of situations where it grows?
Has it multiplied following disturbance?
Does it prefer wet or dry sites?
What other plants are growing with the orchids, including the trees forming the canopy?
Number of plants
Estimate the number of plants or describe the distribution of the plants at the site
Do plants occur in small clumps?
Do plants occur in colonies and if so how large are they?
Size of the plant
What is the height of the flower stem and width of the flower stem?
What are the length, width and shape of the leaf?
Is the leaf flat, channelled (u-shaped) or tubular in section?
Does the leaf change shape along its length?
Does the leaf have parallel ridges?
Is the leaf thick and fleshy or thin and papery?
What colour is the leaf?
Does the leaf have a reddish base and is the red colouration in parallel lines?
Are there any hairs on the leaf and are they confined to the margins?
Is the leaf rigid and upright or is it weak at the tip and falling under its own weight?
What is the tip of the leaf like and does it have a pointed apex?
Are the leaves shiny or to they have a powdery covering?
What is the diameter of the stem?
What is the colour of the stem?
How high is the fistula, the point the point where the stem separates from the leaf?
(Bracts are leaf-like structures along the flowering stem)
How many bracts are there on the stem (ie those that are not immediately below a flower)?
How long is each of these bracts?
What colour are the bracts?
Are the bracts tightly or loosely wrap around the stem?
(Fertile bracts are leaf-like structures at the base of each flower)
How long are the bracts?
What colour are the bracts?
(The ovary is the structure immediately below the petals and sepals that becomes the seed capsule after the flowers are pollinated)
What colour are the ovaries?
How long are the ovaries?
How wide are the ovaries?
What time of the year are the flowers open
What is the length and width of each flower?
Do the petals and sepals open widely, or does the flower remain almost closed?
What colour are the petals and sepals?
Do the petals have spots or darker coloured veins?
Is the labellum larger or smaller than the other segments (petals and sepals)?
Are segments rounded, pointed or cup shaped?
What colour is the outside of the buds?
What conditions are required for the flowers to open? Are they only open in hot, humid conditions?
What colour is the main part of the column?
Describe the post-anther/mid-column lobe
Is there a tubular structure on the top of the column? What colour is this and does it have a collar of a different colour?
Does the lobe have a cleft in the apex and how deep is this?
Does the column have lateral lobes (arms) reaching in front of the column?
Are there trichomes (hair-like structures) in a mop or toothbrush arrangement?
Is there a sharp bend in the column arms?
If there is not a tubular lobe, are there three levels of structures on the column?
Are there papillae (rows of narrow bumps)? How many and what colour are they?
What colour is the crest, if present?
Describe the fragrance of the flower or whether there is none
QUESTION: Are there more than one species called Hare Orchid? This one [Leporella fimbriata] looks different from Leptoceras…? Why are they in different genera?
Originally they were described the genus Caladenia but as the knowledge information increased other genera were created. Thus Leporellafimbriata was put into Eriochilus, as Eriochilusfimbriatus (1882), then Leptocerasfimbriata and finally into its own genus Leporella (A S George 1971). Caladeniamenziesii became Leptoceras menziesii.
This does not answer the why of the question which is about classification but Jones (2006) is helpful when he says:
“Plant classification systems rely on interpreting and measuring the features in one group of plants and comparing these with another group, either seeking difference or similarities. Studies in orchids are usually biased heavily towards features of floral morphology but recent studies have revealed the importance of vegetative features in the roots, stems and leaves. The most successful classification system is one that is balanced and based on a wide range of vegetative and floral features.” To add to this list is the molecular studies being done on orchids.
This means the authors advocating change need to clearly show why a name change and/or a new species is warranted.
For instance, Fitzgerald gives the following reason for not including Leporella fimbriata in the Caladenia genus
“Leaves much more frequently observed than flowers. It is with great reluctance I depart from the naming in ‘Flora Australiensis’ [author Bentham, 1863 – 1878], but I cannot concur with the inclusion of this with Caladenia, and have place it in Lindleys’ Leptoceras for the following reasons: Leaf or leaves not those of Caladenia. In Caladenia I have never seen more than one leaf, always thin and usually hairy; in this plant leaf thick, hard and shining, occasionally two. In Caladenia tubers are generally numerous, in L. fimbriata I have only observed one. The labellum, is without the characteristic glans and is not of the form obtaining in Caladenia, the stigma is very different in form being triangular and deep sunk, the upper parts overhanging, not oval and shallow; and the flowers have the peculiarity of drying and continuing in a state hardly to be distinguished from the fresh flowers long after the seed has been shed. It approaches C. menziesii only (so far as I can see) in having erect linear-clavate petals, in which C. menziesii is itself peculiar, L. firmbriata seems to come near to Eriochilus than to Caladenia but differs from it again” Quoted from Emily Pelloe Western Australian Orchids 1930
Concerning Leptoceras menziesii, Bates & Weber have made the following statement:
“True Caladenias have hairy scapes and hairy leaves. (C. menziesii now believed to belong to a separate genus is glabrous)”.
Even though they are not Caladenia, why not have them in the same genus for both have glabous (without hairs) leaves, more leaves than flowers, erect spathulate (spoon shaped) glandular petals, colony forming, similar distribution.
There are similarities. In fact, Bates (2011) calls them sister genera but despite the similarities there are enough differences to recognise them at genus level at present including “different flowering times, different mycorrhizal fungi associations and different pollination” some of which are detailed in the chart below.
Winged male ants (Myrmecia urens)
Myrmecophyte – lives in mutualistic association with colony of ants
Curved white with red stripes
Wider than longer, purple and green
Has no calli
Spring (September to November)
Autumn (March to May)
Shaded sites – moist gullies; scrub, heath, woodland and foret