Petalochilus – when use of a segregate or common name is helpful

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.

Caladenia carnea (synonym Petalochilus carneus) Photographer Lindsay Ames

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 flava Photographer Pauline Meyer

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.

Caladenia tentaculata (synonym Arachnorchis tentaculata) Photographer Jane Higgs

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.

Caladenia carnea (synonym Petalochilus carneus) Photographer: Rob Pauley

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.

Caladenia prolata (Petalochilus prolatus) Photographer: Helen Lawrence

*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.

References

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.

Photograph Competition & Benched Plants July 2020

Email your votes for both the competition and benched plants to Marg Paech, nossa.editor@gmail.com by 5 pm July 27 2020

1. Thelymitra jacksonii
2. Diuris magnifica
3. Thelymitra cyanapicta
4. Urochilus sanguineus (syn Pterostylis sanguinea
5. Diuris sp
6. Urochilus sanguineus (synonym Pterostylis sanguinea)
7. Pyrorchis nigricans
8. Arachnorchis leptochila (synonym Caladenia leptochila)
9. Prasophyllum australae
10 Paintings of Caleana major, Corybas diemenica and Diuris orientis

BENCHED PLANTS

A. Pterostylis robusta, Red Form
B. Pterostylis ‘Nodding Grace’
C. Pterostylis robusta
D. Pterostylis sanguinea
E. Acianthus pusillus

NOSSA: The Doco

Last year, UniSA second year media students were required to produce a short documentary about a local organised. Three of their students, Vanessa Rossi, Tayla Elliot and Emma Sullivan, chose to produce a video about the work of the Native Orchid Society of South Australia. And for this we thank them. It was interesting working with them and they learnt a few things about our bush gems – namely that they are not big and showy!

Some adjustment needed to be made to the original video, but it is now available for viewing

It’s Arrived, the Wild Orchid Watch App …

The process may have taken awhile, (for some longer than than the two years collaboration with the University of Adelaide,) but finally the Wild Orchid Watch app is now available for all Australians to use.

Glossodia major

So why orchids…

  • Orchids are iconic and somewhat mysterious plants that are highly valued by sections of our society.
  • They are sensitive to environmental change most of which puts the survival of populations at risk of being lost permanently.
  • Orchids tend to be indicators of ecosystem health.
    • They are dependent on other parts of the ecosystem such as fungi within the soil and particular insect pollinators .
    • These insects are also dependent on a functioning ecosystem for their survival.

Thus, when orchids are conserved other parts of the ecosystem are also conserved resulting in broader benefits to the ecosystem as a whole.

Diplodium sp Adelaide Hills

So, why an app …

  • traditional methods of data collection for orchids are inadequate because of their
    • differences in emergence with seasons
    • short flowering, sometimes non-flowering, seasons
  • allows the collection of a wealth of knowledge known to orchid enthusiasts
  • this method of collecting data enables researchers to gain a better understanding of
    • the conservation status and trend of orchids
    • the value of orchids as indicators of environmental change
    • the phenology (life cycle), distribution and abundance of orchids

The WOW app allows citizens scientists to provide important data for researchers.

Bonus Benefit of the App – Identification

Probably one of the most frustrating things for the novice is not knowing what is the species of orchid that they have found. With this app it is not necessary to be familiar with all the orchid species.

The WOW app uses the iNaturalist platform where there is a whole community ready to assist with identification.

One can be an orchid citizen scientist without a detailed knowledge of orchids.

So, hop over to the WOW website to find more information, instructions and download the app.

Orthoceras stricta

South Australia’s Arachnorchis cardiochila

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.

COVID19 Impact on NOSSA

Update September 2020

With recommencement of various NOSSA activities we have put into place the Government required Covid19 plans with Covid Marshalls.

If you have any concerns, please feel free to contact NOSSA on 0439214106, or email the secretary or go to the South Australian government website for more details.

March 21 2020
NOSSA will put best practice to prevent the spread of COVID19 into action to protect our members. Ramifications of this decision include the following –

Postponement of NOSSA AGM and general meeting until further notice.
Our planned speaker, Dr Rick Davies, was relieved to hear that we had postponed our meeting next week because he was concerned for our members.

NOSSA Committee Meetings
The plan is to manage these meetings electronically so that the affairs of NOSSA are properly canvassed and effective decisions are made.

Propagation Days
These will be placed on hold for the time being.

Field Trips
These are not necessary meetings and will not be formally arranged by NOSSA however going for a walk looking at orchids is something that family groups are able to do outside. NOSSA and the Update may offer a suggested place to visit to encourage this.

WAYS TO STAY IN TOUCH
Journal
Our wonderful editor, Marg, will continue to ensure the Journal meets the monthly deadline, and her team of trusty helpers will ensure it gets tot he members. The Journal is the official source of Orchid news and information so look out fot it each month. Feel free to send your thoughts to the editor – they may even get published!

Facebook
Some members are already familiar with our Facebook pages. Others may be interested in exploring this avenue of member interaction.
If you have any questions etc, email nossa.enquiries@gmail.com

Photographic Competition
Please continue to send your wonderful photos into nossa.enquiries@gmail.com. The photos will be displayed for voting. 😉 Still working on the how of that thought!

Update
Update will continue to keep you in the loop of NOSSA news at mid-month.

CANCELLED EVENTS
There have been many events that have been delayed, postponed or cancelled. Some of the follow –
Mt Pleasant Show
APS Autumn Sale
SAROC AGM and meeting

***GOOD NEWS***
Library Display
We couldn’t take part in the Mt Pleasant Show, however Faye McGoldrick of the Mt Pleasant Natural Resource Centre invited us to put up a display in their library. Rosalie and Robert Lawrence have already put the display in place, so if you are passing pop in and have a look.

We encourage everyone to stay safe and follow the basics of social distancing and washing hands to minimize inviting COVID19 into your world.

Stay well, Stay happy
Til next time

Lindy McCallum
Honorary Secretary NOSSA

Terrestrial Culture – December & January

The following two articles are from the December 2019 NOSSA Journal. Written by Les Nesbitt, they cover the months of December and January.

Terrestrial Culture – December

A few late orchids such as Diuris drummondii may still have green leaves and flowers so will need watering every couple of days. Most terrestrials will have died down by now on the Adelaide Plain. Watering consists of a quick squirt with the hose once a week to moisten the top 1 cm to prevent tubers shrivelling. A small terrestrial collection of pots can be moved to a cooler place out of direct sun under a bench or to the south side of the house. A large collection must stay on the benches so extra shadecloth is added for the summer.

Repotting is in full swing now. Keep a stock of the required materials on hand including sand, soil, native potting mix, clay, blood & bone, chopped sheoak needles, smashed and sieved gum leaves pots labels, shadecloth squares for crocking, pencils to write on plastic, sieve and bowl, watering can & shadehouse benching. A system for washing and sterilizing pots before reuse is essential to control disease and virus.

Pots dry out quickly in hot windy weather. Water a day or two before repotting so that the potting mix is just moist. If too dry dust will be a problem and tubers can be damaged by hard lumps of mix. Too wet and the mix sticks to the tubers and clogs the sieve. The ideal is a mix that is easy to work when separating wet pots take tubers from mix. It helps to move some pots under cover in case of rain. Wet pots take several days to dry out which can hold up repotting. Alternatively, a sheet of plastic over the pots when rain is forecast will shed the water but remember to weigh it down with bricks or it will blow away.

Pick out the tubers and put them in a kitchen sieve sitting in a container of water. Use a jet of water to wash the tubers clean and spread them on a towel to dry. Discard any tubers that are soft or have turned black. If the tubers are healthy, firm and a pale colour the mix can be reused. Colony type tubers should have at least doubled in number since last year. Add half fresh mix to the old mix and add a big pinch of blood & bone fertilizer. Should the old mix be dark in colour, or the tubers not be healthy looking then throw out the old mix and pot up in new mix.

Select the pot size, place a shadecloth square in the pot to retain the mix when it dries out. Fill the pot with mix to about 2cm from the top. Select the largest tubers for a show pot and push them into the mix with the shoot on top. The small tubers can be potted in another pot to grow bigger next year. Cover the tubers with more mix and almost fill the pot. Firm the mix down with your hand or use the bottom of an empty pot. Cover the surface with chopped sheoak needles. Write out a label with the name of the orchid and the provenance,
if known. On the back of the label note the number of tubers and the date planted. Water the pot gently so as to not disturb the needles. This helps settle the soil around the tubers and makes subsequent watering easier. Put the finished pots back in the shadehouse to await the next growing season.

Send off your tuber bank order before Christmas or you might miss out on your choices. The tuber bank is a great way to increase your terrestrial collection.*

*Tubers are sold only to financial members

Terrestrial Culture – January

Start watering the blue tag pots in January. Pots of orchids from the East Coast of Australia where it rains in Summer are given a blue tag as the culture is different compared to local terrestrial orchids. This early shooting group includes most cauline greenhoods, Pterostylis baptistii and Corybas hispidus. Local South Australian tubers can be kept completely dry until at least mid-February if pots are shaded.

When your tuber bank order arrives, pot up the tubers straight away. Plant each species in a separate 125mm or 150mm pot. Don’t forget to record the provenance name (if known) on the label and in your recording system. The
provenance is the location of the original collection. Provenance is important because in 10 years the orchid will possibly be extinct in that area as suburbia expands or weeds take over the habitat.

Summer watering is important. Too little and tubers may dry up. Too much and they may rot or come up early before the heat of summer is over when they will be attacked by thrip and aphids. A light sprinkle on top of the pots once a
week works OK.

Try to finish repotting this month. If left until February there is more chance of breaking off the new shoots which can be well developed by late February.