Banner for Great Southern BioBlitz wildlife exploration event with people walking below in a forest

2024 Great Southern BioBlitz

Esperance, Helms Arboretum, List of Orchids Found, Western Australian Orchids

It is the 20th September and I am participating in the Great Southern BioBlitz (GSB) this year.
The GSB runs from the 20th to 23rd of September.
The purpose of the GSB is to record as many observations in iNaturalist of any living thing or trace of such (i.e. feathers, footprints etc.).
Due to its proximity to Esperance and its unusually high diversity I will be checking out Helms Arboretum (Mud Map SE35).
I recorded all species I photographed on iNaturalist but will only record the orchids in this BLOG

18/09/2024 – Helms Arboretum revisited

Esperance, Helms Arboretum, List of Orchids Found, Western Australian Orchids

After what seems like forever, we finally get back to check out Helms Arboretum to see what is flowering in mid-September.

As expected, we are not disappointed with many different species found.

Listed in no particular order are the orchids found grouped together for recording purposes.

Purple enamel orchid

Elythranthera brunonis

Flower: Aug to early Nov


Cowslip orchid

Caladenia flava subsp. flava

Flower: Jul to early Dec


Little pink fairy

Caladenia reptans subsp. reptans

Flower: Jul to early Oct


Un-named hybrid orchid

Caladenia flava x C. reptans

Parents flower: July to early Oct / Dec


Lemon-scented sun orchid

Thelymitra antennifera

Flower: Jul to Oct


?? snail orchid

Pterostlyis sp.

Unsure of ID.. Possibly the un-named species assigned to Helms Arboretum


Bee orchid

Diuris laxiflora

Flower: Sept to early Nov


Common bee orchid

Diuris decrementa

Flower: Late Aug to early Nov


Red beaks

Pyrorchis nigricans

Flower: Aug to Oct


Un-named hybrid orchid

Thelymitra antennifera x T.graminea

T. antennifera flowers: Jul to Oct


Shy sun orchid

Thelymitra graminea

Flower: Sept to mid-Nov


Esperance king spider orchid

Caladenia decora

Flower: Mid-Aug to Oct


Heberle’s spider orchid

Caladenia heberleana

Flower: Sept to Oct


Un-named hybrid spider orchid

Caladenia decora x C. longicauda

I have decided name this hybrid the Esperance spider orchid due to both parents being names Esperance King and Esperance White respectively.

Flower: Aug to Oct


Rattle Beaks

Lyperanthus serratus

Flower: Sept to Nov


Zebra orchid

Caladenia cairnsiana

Flower: Aug to early-Nov


Esperance white spider orchid

Caladenia longicauda subsp. crassa

Flower: Aug to early-Oct


?? spider orchid

Caladenia sp.

Appears to be further Caladenia longicauda. However, they do not have the usual white colouring or the red labellum of a C.decora hybrid.


Esperance white spider orchid

Caladenia longicauda subsp. crassa

Hypochromic variant


Common mignonette orchid

Microtis media subsp. media

Flower: Sept to Jan


Well, it was an amazing day out in the Arboretum, with the finds including 3 different hybrids and a hypochromic variant.
Species from 8 different genera were located which confirms this location to be one of the premier spots in the SE Coastal area of WA.

Unfortunately, in the summer of 2024/25 an uncontrolled bush fire destroyed large areas of the arboretum and to this day (12/06/2026 it is closed to the public.

Fingers crossed it will be open before the 2026 season is finished.

Top Orchids Found West of Esperance: A Field Report; Part I

Day Trip, Lake Mortijinup NR, Nature Reserves, Western Australian Orchids

















Only a little way up the road will pull over at another random spot due to a change in vegetation cover.
First up hiding underneath a shrub a compact clump of Western tiny blue orchids is found.


An exciting find here was a small patch of the Dwarf shell orchid (Pterostylis brevichila). These orchids are found flowering between Hyden and Mount Arid.


Another new orchid for today is found, from the Caladenia genus, which is always exciting. The Short-sepaled spider orchid (Caladenia brevisura) is another easterly located orchid, as it grows between Ravensthorpe and Israelite Bay.

The next orchids found are the small Zebra orchid (Caladenia cairnsiana) and the Frog greenhood (Pterostylis sargentii) which are found from Watheroo to Esperance and Mullewa to Grass Patch respectively.


Then some further Esperance white spider orchids and Small mantis orchids are found. As usual I will post a pic of each for recording purposes.


As we proceed, we take a moment to reflect on the discovery of 15 distinct species of orchids. With additional locations yet to be explored, this promises to be a highly successful orchid hunting expedition.
As I compose these blog posts several months after the actual date, I am dividing this day into three reports. Stay tuned for Part II and III.

Orchid Hunting Adventure East of Esperance: 28 Unique Species

Mount Burdett NR, Mount Ridley NR, Western Australian Orchids

(Caladenia horistes)



























Cream spider orchids blowing in the wind




















Orchid diversity in Coomalbidgup and East Munglingup

Western Australian Orchids



































15/09/2023 ….. Final day of 2023 Road Trip :(

Beaumont NR, Clyde Hill NR, Condingup Water Reserve, Nature Reserves, Numerous days, Other Reserves, Road Trip
































20/08/2023 ….. Southern Curly-Locks and Pink Bunny Orchid | Orchid Discovery West of Esperance

List of Orchids Found, Sunday Drive, Western Australian Orchids

Esperance King Spider Orchid

(Caladenia decora)


Cowslip orchid

(Caladenia flava subsp. flava)


Blue beard

(Pheladenia deformis)


Pink bunny orchid

(Eriochilus scaber subsp. scaber)


Pink fairies

(Caladenia latifolia)


Spectacular spider orchid

(Caladenia x spectabilis)

Parents: C. flava / C. latifolia


Lort River snail orchid

(Pterostylis lortensis)

Small rosette 12-36mm across

Banded greenhood

(Pterostylis vittata)



(Eriochilus scaber subsp.scaber)



Red Beaks

(Pyrorchis nigricans)


(Diuris littoralis)


Blue beard

(Pheladenia deformis)


Little pink fairy

(Caladenia reptans subsp. reptans)


Banded greenhood

(Pterostylis vittata)



Little pink fairy

(Caladenia reptans subsp.reptans)


Pink bunny orchid

(Eriochilus scaber subsp. scaber)

I just had to post this picture

Blue beard

(Pheladenia deformis)


Western tiny blue orchid

(Cyanicula aperta)


Red beaks

(Pyrorchis nigricans)


Bee orchid

(Diuris laxiflora)


Reaching spider orchid

(Caladenia arrecta)



South coast donkey orchid

(Diuris brockmanii)


Cowslip orchid

(Caladenia flava subsp. flava)


Pink bunny orchid

(Eriochilus scaber subsp. scaber)


Stark white spider orchid

(Caladenia longicauda subsp. eminens)


Leaving Munglinup we head southeast to Springdale Nature Reserve. A quick inspection of this location turns up more orchids, including a new species for the day.


South coast donkey orchid

(Diuris brockmanii)


Southern curly-locks

(Thelymitra uliginosa)


Pink bunny orchid

(Thelymitra uliginosa)


06/08/2023 ….. Discovering a Diverse Array of Orchids in East Esperance: A Photographic Journey

Condingup Water Reserve, Other Reserves, Sunday Drive, Western Australian Orchids
















08/10/2022 & 09/10/2022 ….. Jacup Jewels

Numerous days, Road Trip, Western Australian Orchids

Upon leaving the Jerramungup burnt are we head east looking for somewhere to park up for the night. We make it about 35kms when we pull into the Jacup Highway Park at the Fitzgerald River crossing. This will do, so we set up the camper and I do my best to drive over a log in my Ford Falcon, not the greatest idea ๐Ÿ™‚ I’ve had.

Now we still have the late afternoon to go orchid hunting. As per our previous visit to this location, we are not disappointed. First, we find the Green spider/Fringed mantis orchid (Caladenia falcata) flowering in isolation and in small groups over the entire area we checked out.

As can be seen in the picture above the hybrid, Wheatbelt spider orchid (Caladenia x cala) was also found. It was amazing how many were actually found, as we usually find one or two only in each location.

And of course, we also found the other parent for the hybrid. The Stark white spider orchid (Caladenia longicauda subsp. eminens) occurs as far east as Ravensthorpe and grows in open woodlands so seems to fit the bill.

Next, we find the very special Lazy spider orchid (Caladenia multiclavia) which is recorded as occurring between Wongan Hills, Borden and Ravensthorpe. This unusual looking orchid is known for its upright petals and sepals plus the smooth striped labellum with a dense band of bristly headed calli.

We also come across a mixture of other orchids but not in great numbers, so I will record then with only 1 pic each. Firstly, there is the ever-reliable Cowslip orchid (Caladenia flava subsp. flava) and Common mignonette orchid (Microtis media subsp. media). Both are common, widespread orchids. Then the more rarely found, without a recent summer fire, Red Beaks (Pyrorchis nigricans) is discovered with a nine-flower inflorescence. Finally, a pale coloured Pink candy orchid (Caladenia hirta subsp. rosea) and possibly a Ravensthorpe rufous greenhood (Pterostylis leptochila) yet to fully flower are found.

One orchid not expected was the Common dragon orchid (Caladenia barbarossa) which is found flowering between Bindoon and Munglinup. There are only 4 species of dragon orchids, and all are endemic to WA. Only 2 specimens found but still very happy.

However, one final orchid is found in decent numbers. The Drooping spider orchid (Caladenia radialis), is found flowering between Northampton and Ravensthorpe from August to October. The labellum can have smooth margins or tiny marginal teeth.

Back to camp due to the fading light.

Small campfire lit

We awake to a beautiful sunny morning, have breakfast then decide we will take some time this morning to complete a search down to the river. Fingers crossed for something new.

First up though I will post pictures of those orchids we come across that we also found in our afternoon search yesterday.

Now for the new findings of the location. The Short-sepaled spider orchid (Caladenia brevisura) is found between Jerramungup and Israelite Bay from August to October. Only one specimen found, and not the best picture, but a record non the less. Another sole specimen found was that of the Bee orchid (Diuris laxiflora) which flowers September to early November between Gingin and Esperance.

Blue sun orchids are found in good numbers closer to the river. Now identifying them is needed. As I am writing this account over 12mth later I am identifying them from pictures taken. Based on these I feel some to be Scented sun orchid (Thelymitra macrophylla) due to the broad leaf and large numerous flowers. Others though have thin leaves with fewer flowers, so are most likely the Shy sun orchid (Thelymitra graminea). Both are recorded as flowering in the Shires of Ravensthorpe and Jerramungup during the month of October.

It is 11am so we had better push on as we need to arrive home in Esperance today. One last stop is made at Kukenarup Memorial, where we enjoy a spot of lunch before one last exploration for orchids.