Biodiversity

Species Profile and Threats Database


For information to assist proponents in referral, environmental assessments and compliance issues, refer to the Policy Statements and Guidelines (where available), the Conservation Advice (where available) or the Listing Advice (where available).
 
In addition, proponents and land managers should refer to the Recovery Plan (where available) or the Conservation Advice (where available) for recovery, mitigation and conservation information.

EPBC Act Listing Status Listed as Endangered as Caladenia viridescens
Recovery Plan Decision Recovery Plan required, included on the Commenced List (1/11/2009).
 
Adopted/Made Recovery Plans National Recovery Plan for Dunsborough Spider Orchid Caladenia viridescens (Patten, J., A.P. Webb & A. Batty, 2008) [Recovery Plan] as Caladenia viridescens.
 
Other EPBC Act Plans Threat Abatement Plan for Competition and Land Degradation by Feral Rabbits (Environment Australia (EA), 1999c) [Threat Abatement Plan].
 
Policy Statements and Guidelines Draft survey guidelines for Australia's threatened orchids (Department of the Environment, 2013b) [Admin Guideline].
 
Federal Register of
    Legislative Instruments
Declaration under s178, s181, and s183 of the Environment Protection and Biodiversity Conservation Act 1999 - List of threatened species, List of threatened ecological communities and List of threatening processes (Commonwealth of Australia, 2000) [Legislative Instrument] as Caladenia viridescens.
 
Amendment to the list of threatened species under section 178 of the Environment Protection and Biodiversity Conservation Act 1999 (11/04/2007) (Commonwealth of Australia, 2007f) [Legislative Instrument] as Caladenia viridescens.
 
State Government
    Documents and Websites
WA:Declared Rare and Poorly Known Flora in the Central Forest Region. Part 2 (Williams, K., A. Horan, S. Wood & A. Webb, 2001) [State Species Management Plan].
State Listing Status
WA: Listed as Critically Endangered (Wildlife Conservation Act 1950 (Western Australia): September 2013) as Caladenia viridescens
Scientific name Caladenia viridescens [56776]
Family Orchidaceae:Orchidales:Liliopsida:Magnoliophyta:Plantae
Species author Hopper & A.P.Br.
Infraspecies author  
Reference Hopper, S.D. & Brown, A.P. (2001), Nuytsia 14(1/2): 158-9
Other names Caladenia viridescens Hopper & Brown ms. [67226]
Caladenia viridescens Hopper & A.P.Brown ms. [67351]
Arachnorchis viridescens [78689]
Distribution map Species Distribution Map

This is an indicative distribution map of the present distribution of the species based on best available knowledge. See map caveat for more information.

Illustrations Google Images

The current conservation status of the Dunsborough Spider-orchid, Caladenia viridescens, under Australian and State Government legislation and international conventions, is as follows:

National: Listed as Endangered under the Environment Protection and Biodiversity Conservation Act 1999.

Western Australia: Listed as Declared Rare Flora under the Wildlife Conservation Act 1950.

Scientific name: Caladenia viridescens

Common name: Dunsborough Spider-orchid

The Dunsborough Spider-orchid stands from 25–40 cm high and has a single leaf, 15–20 cm long and 5–8 mm wide. It displays one to three flowers, which are pale yellowish-green, stiffly held and which have a narrow labellum. The flowers are similar in size and shape to those of Bussell's Spider-orchid (Caladenia busselliana) but differ in having smaller flowers, stiffly splayed petals and a red tipped labellum. Although the plants are perennial herbs, they are reduced to a below-ground storage organ (tuber) in summer, re-emerging in autumn and flowering from mid-September to late October (Patten et al. 2008).

Dunsborough Spider-orchid is endemic to Western Australia and is found in the vicinity of Dunsborough, approximately 200 km south of Perth in the South West Natural Resource Management (NRM) region (WA DEC 2007). The species occurs over a linear range of 12 km near the northern end of the Leeuwin-Naturaliste Ridge (Patten et al. 2008).

The extent of occurrence is calculated to be 25.7 km². The extent of occurrence was calculated by drawing a boundary around all the known subpopulations to create a polygon. The computer program Arcview GIS and a dataset taken from DEC's Threatened Flora Database (which contains a single GPS coordinate for each subpopulation) was used to determine the area of the polygon. It is likely that the species may suffer a decline in extent of occurrence in the future as subpopulations have been recorded as being in decline (WA DEC 2007).

There is insufficient data to calculate the actual area of occupancy as only subpopulations 1b and 1c, which have a combined area of approximately 8 m², have been recorded. Based on extrapolations of this data over the seven subpopulations, the area of occupancy is estimated to be approximately 0.000056 km² or 56 m².

There is no data available to show a decline in area of occupancy of this restricted species. However, as this species is known from just a few scattered localities in the Dunsborough area, it is likely that the future area of occupancy of this species may decline (Brown et al. 1998; WA DEC 2007).

The species is known from seven locations in the Dunsborough area. Survey in similar habitat by DEC staff has failed to locate any additional subpopulations (WA DEC 2007).

The species distribution is considered to be fragmented as the known subpopulations are scattered with considerable distances between them (WA DEC 2007).

Dunsborough Spider-orchid was first collected from a road reserve near Dunsborough in 1985. More than 20 plants were found at this time. Eight plants were located at this subpopulation (subpopulation 1) in 2001. There are now seven subpopulations and monitoring by DEC staff indicates that the numbers fluctuate and are generally in decline. The presence of the Dunsborough Spider-orchid at subpopulation 5 cannot be confirmed, as the plants have never been relocated. There was a summer fire at this location in 1993–94 that was expected to stimulate flowering and further recruitment; however this does not seem to have occurred despite repeated surveys in 1994, 1997, 1999, 2000 and 2001. Surveys in 1999 located one new subpopulation (subpopulation 6) near subpopulation 2 but this was not relocated again until 2002 (Patten et al. 2008; WA DEC 2007).

The species has been surveyed regularly by DEC staff at its known locations.

Survey Effort of all known Dunsborough Spider-orchid subpopulations (WA DEC 2007).

Subpopulation Survey History Number of Plants Recorded Condition
1a 26/09/1985
23/09/1986
25/09/1988
17/10/1991
30/09/1998
18-20/09/2002
20
20
0
0
0
10 (includes 1b and 1c)
Moderate to good
1b 23/09/1986
18/10/1996
30/10/1998
04/10/2000
02/10/2003
4
20+
0
3
32 (includes 1c)
Moderate to good
1c 16/09/1997
30/09/1998
18/10/1999
07/09/2000
6, 11 and 18/09/2001
12/10/2006
6
9
6
2
8 (includes 1a and 1b)
6
Moderate to good
2 22/09/1999
20/10/1997
30/09/1997
21/09/1986
06/10/2000
11/09/2001
17
5
0
1
3
4
Healthy
3a 09/09/1984
25/09/1985
25/09/1986
18/09/1996
13/10/1994
18/10/1996
04/10/2000
6
10
10
3
20+
3
1
Moderate
3b 30/09/1997
30/09/1998
07/10/1999
04/10/2000
11/09/2001
20/09/2002
1
2
2
1
1
2
Moderate
4 17/10/1990
30/09/1997
14/10/1998
18/10/1999
03/10/2000
11/09/2001
07/10/2001
20/09/2002
16/10/2002
11/10/2003
12/10/2006
30
2
2
1
5
0
4
0
1
7
1
Moderate
5 1986
1994
30/09/1997
15/10/1999
04/10/2000
11/09/2001
20/09/2002
23/10/2006
several
0
0
0
0
0
0
0
Moderate
6 19/10/1999
2000
11/09/2001
21/09/2002
1
0
0
1
Healthy
7 11/09/2001
18/09/2002
22/09/2004
23/10/2006
3
5
7
0
Healthy

The total population size for this species is 64 mature plants across seven subpopulations (WA DEC 2007). Subpopulations are defined according to land tenure and management, as well as location. Most subpopulations have experienced declines in population size (WA DEC 2007).

As the species is known from seven subpopulations in restricted areas that are subject to serious threats, all known subpopulations are important for the species' recovery and long-term survival (WA DEC 2007).

All subpopulations except 3b and 6 have experienced declines in population size. The presence of Dunsborough Spider-orchid at subpopulation 5 cannot be confirmed, as the plants have never been relocated (WA DEC 2007).


One hybrid (with an unknown species) was recorded (WA DEC 2007).

The following subpopulations are in reserves:

Subpopulation 1: Crown Land - Shire Road Reserve
Subpopulation 1b: Crown Land - Shire Reserve
Subpopulation 1c: Crown Land - Shire Conservation Park
Subpopulation 2: Crown Land - Meelup Regional Park
Subpopulation 3a: Crown Land - Shire Rubbish Reserve
Subpopulation 3b: Crown Land - Shire Road Verge
Subpopulation 4: Crown Land - Non-vested Reserve
Subpopulation 5: Crown Land - Leeuwin Naturaliste National Park
Subpopulation 6: Crown Land - Meelup Regional Park
Subpopulation 7: Crown land - Meelup Regional Park

Subpopulation 5 falls within the DEC reserve system, but no plants have been located there since 1986. The remaining known subpopulations are on Crown Land vested in other government bodies. They may at some time in the future become incorporated into the DEC reserve system (WA DEC 2007).

Dunsborough Spider-orchid grows in loam and grey sand with a preference for well-drained soils rather than swampy habitats (Western Australian Herbarium n.d.). It favours Marri (Corymbia calophylla) and Peppermint (Agonis flexuosa) woodlands in well-drained lateritic and sandy loam soils. It can also occur on coastal heath with Calothamnus graniticus subsp. graniticus and Hakea trifurcata (Patten et al. 2008). The species grows with several other members of the Caladenia complex including the Karri Spider-orchid (C. brownii), Cowslip Orchid (C. flava), Swamp Spider-orchid (C. paludosa) and in one area grows with the threatened Bussell's Spider-orchid (Brown et al. 1998; Hoffman & Brown 1992; Hopper & Brown 2001b; Papenfus et al. 1997b).

Bussell's Spider-orchid also occurs with Pimelea hispida, Grevillea quercifolia, Xanthorrhoea preissii, Kingia sp. and Hibbertia sp., Calothamnus graniticus, Hakea lissocarpha and Hypocalymma angustifolia (WA DEC 2007).

This species grows in association with Bussell's Spider-orchid, listed as Endangered under the EPBC Act, at subpopulation 4 (WA DEC 2007).

Dunsborough Spider-orchid has a growing phase from April through to early November. The orchid remains below ground during the dry summer as a dormant tuber. Following the first seasonal rains a single leaf appears above ground. Orchid seedlings are dependent on a specific mycorrhizal fungus for seed germination and nutrition. During late autumn, the replacement tuber is initiated and continues to develop until late in the growing season. The survival of the plant to the following growing season is dependent on the presence of this tuber to survive the period of summer dormancy. Further research is needed into understanding the interactions between leaves and tubers as 'sinks' for resources. It seems likely that tubers must reach a critical size to sustain dormancy throughout the summer (Batty et al. in prep., cited in Patten et al. 2008).

Dunsborough Spider-orchid flowers from September to October (Brown et al. 1998; Williams et al. 2001). The pollinating mechanism is likely to be by insects such as wasps due to the species floral structure.

Not all plants will produce flowers in any one year. Generally, for every plant in flower, a number of vegetative plants will be present. The proportion of flowering to non-flowering individuals is influenced by environmental conditions including the presence or absence of summer fire and the amount of rainfall received during winter and spring (Batty et al. in prep., cited in Patten et al. 2008).

Flowering individuals will produce a bud when resprouting from the dormant tuber. The bud develops quickly mid-way through the growing season and continues to grow until flowering. Plants flower for approximately two weeks or until pollination occurs, after which flowers collapse and if pollination was successful a seed capsule develops. The capsule swells as the seed matures, and this can take from six to eight weeks to develop depending on climatic conditions. If temperatures are higher than average, seeds may mature faster. Prior to seeds being released the green capsule turns yellow and then brown. Small slits develop in the capsule from which the seed is dispersed. Up to 30 000 seeds can be produced in the one capsule (Batty et al. in prep., cited in Patten et al. 2008).

Seeds will remain dormant in the soil over summer until the break of the season the following year. Once wet, the seeds imbibe water and the seed coat splits. At this point, infection by a suitable fungus is required for germination to occur, which will result in a protocorm and the subsequent development of a seedling. Not all of seedlings will mature, as those that fail to produce a tuber will not survive dry summer conditions. If no fungus is present, seed remains in the soil throughout the growing season, and those that are not eaten, are killed by dry summer conditions (Batty et al. 2000, 2001 cited in Patten et al. 2008).

Orchid seedlings are very small for the first growing season and are difficult to locate. Leaves are typically less than 20 mm long and only a few millimetres wide. It appears that leaf and tuber size will then increase over the next two to five years, providing there have been suitable environmental conditions, until they become adult plants capable of flowering (Patten et al. 2008).

The patchy distribution of individual plants within populations may indicate natural recruitment is by seed dispersal rather than the production of multiple root tubers (Papenfus et al. 1997b).

This species has smaller flowers than the Swamp Spider-orchid and differs from Bussell's Spider-orchid in having a red tipped, rather than cream tipped labellum. Dunsborough Spider-orchid generally grows in well-drained soils, rather than the swampy habitats preferred by the above-named species; however, it is occasionally found in the same locality (Brown et al. 1998; Papenfus et al. 1997b).

The above ground parts of this plant are most evident when a flower has been produced during the spring period. Therefore, detectability is optimum during the species flowering period from September to October (Brown et al.1998). Any additional survey should be focused on the known subpopulations and remnant vegetation in similar soil and vegetation types (WA DEC 2007).

Threats to Dunsborough Spider-orchid subpopulations (WA DEC 2007).

Subpopulation Past Present
1a   Road maintenance, weed invasion, grazing, trampling, fire, poor recruitment
1b   Road maintenance, weed invasion, grazing, trampling, fire, poor recruitment
1c   Weed invasion, grazing, trampling, fire, poor recruitment
2   Weed invasion, grazing, trampling, fire, poor recruitment
3a   Weed invasion, grazing, rubbish dumping, fire, poor recruitment
3b   Road maintenance, weed invasion, grazing, trampling, fire, poor recruitment
4 Rubbish dumping Weed invasion, grazing, trampling, fire, poor recruitment
5   Weed invasion, grazing, trampling, fire, poor recruitment
6   Weed invasion, grazing, trampling, fire, poor recruitment
7   Weed invasion, grazing, trampling, fire, poor recruitment

In the past, land clearing has been one of the main threats to this species across the landscape, although not necessarily to these subpopulations. Vegetation clearance has significantly reduced suitable habitat and is probably the major factor contributing to its rarity.

The species is also particularly vulnerable to weeds, road maintenance activities and to destruction from fire during its growing season.

Fire
Fire during late autumn, winter and early spring can kill flowering plants or prevent seed set. Too frequent fires can result in weed invasion. However, Dunsborough Spider-orchids may flower in the spring following fires that occur when the plant is dormant. If areas are left unburnt for too long, undergrowth and weeds are likely to flourish and have a negative impact on the Dunsborough Spider-orchid (Patten et al. 2008; WA DEC 2007).

Grazing
Grazing by kangaroos, rabbits or stock has had an impact on all subpopulations. Insect damage has also been observed in some subpopulations. The high level of palatable weeds near the subpopulations and in adjacent farming properties attract herbivorous animals, which are often unselective in their grazing (Patten et al. 2008).

Habitat Degradation
Subpopulation 2 occurs very close to the coastal walk trail (within 1 m) and there is the potential for trampling, although this threat has the potential to affect all subpopulations. Orchids are particularly prone to being picked (which is illegal). While this may not kill the plant, it does affect the plant's ability to set seed, which in turn affects recruitment. Soil compaction through establishment of tracks from walking can also have negative effects on regeneration potential (Patten et al. 2008; WA DEC 2007).

Raod Maintenance
Road maintenance has had an impact on subpopulation 3 in the past, where Dunsborough Spider-orchid grows within 2 m of the road's edge. Threats to roadside subpopulations include grading, chemical sprays, construction of drainage channels and the mowing of roadside vegetation. Several of these actions also encourage weed invasion (Patten et al. 2008).

Recruitment
Poor recruitment threatens all subpopulations with few plants developing seed without artificial assistance. Even when seed is produced, it is suspected that low orchid recruitment rates from seed dispersed in their natural environment may, in part, be due to the patchy distribution of mycorrhiza in soils (Scade et al. in prep., cited in Patten et al. 2008).

Subpopulation 4 had been affected by grazing and weeds in 2003, although the plants within the fenced area of the verge bush were healthy. This subpopulation has also been affected in the past by rubbish dumping. The track was closed in 1999 and this has restricted vehicle access and hence, further rubbish dumping (Patten et al. 2008).

The National Recovery Plan for Dunsborough Spider Orchid Caladenia viridescens (Patten et al. 2008) lists the following recovery actions. These actions will be monitored by the WA DEC through the South West Region Threatened Flora and Communities Recovery Team (SWRTFCRT).

Coordinate Recovery Actions
This will be undertaken by the South West Region Threatened Flora and Communities Recovery Team (SWRTFCRT).

Stimulate seed set
Flowers of the species will be artificially hand pollinated to stimulate seed set. This is necessary to allow for in situ germination and to produce enough seed for collections.

Collect seed and fungal material
Preservation of germplasm is essential to guard against extinction if wild populations are lost. This will be undertaken by the Botanic Gardens and Parks Authority (BGPA) and DEC, through the SWRTFCRT.

Conduct further surveys and Monitor Populations
Community volunteers will be encouraged to participate in further surveys supervised by DEC staff.

Complete and implement the fire management strategy
A coordinated fire response plan has been developed for the South West Region and incorporated in to the Fire Control Working Plan. It includes strategies for fire control for the habitat of each subpopulation.

Obtain biological and ecological information
Improved knowledge of the biology and ecology of the Dunsborough Spider-orchid will provide a better scientific basis for its management in the wild.

Undertake translocation
As the number of extant plants is very low and subpopulations are not secure from threats, a translocation proposal is currently being developed.

Stimulate flowering
Numbers of flowering specimens in most subpopulations have been declining recently. Where the species occurs in habitat that has not been subject to recent disturbance, such as fire, and numbers of flowering individuals have declined, selected areas will be subject to small trial recovery burns or to other disturbances such as raking (e.g. subpopulation 4). Fire will be introduced at an appropriate time to reduce fuel loads, to minimise fire hazard, to reduce competition from other vegetation at the site, and to stimulate germination to attempt to increase numbers in the subpopulation. This should be undertaken between mid-November and mid-April to ensure that above ground parts of the orchids are not damaged.

Map critical habitat
It is a requirement of the EPBC Act that spatial data relating to critical habitat be determined. WA DEC intends to do so, however, it depends on the priority of other recovery actions and resources available.

Continue weed control
As a consequence of weed control undertaken in previous years, the current level of threat from weeds is low. If monitoring indicates that the threat from weeds has increased, weed control will be undertaken in consultation with the relevant landholders.

Control rabbits
Subpopulation 4 was fenced to prevent grazing by rabbits. If monitoring indicates that the rabbits are impacting on other subpopulations through grazing and digging, rabbits will be controlled using appropriate control methods, in consultation with the landholders.

Liaise with land managers
Staff from DEC's Blackwood District will continue to liaise with land managers and owners to ensure that subpopulations are not accidentally damaged or destroyed. Input and involvement will also be sought from indigenous groups that have an active interest in areas that are habitat for Dunsborough Spider-orchid.

Seek to improve the security of subpopulation 4
Subpopulation 4 is currently located in a Shire reserve. DEC will continue to seek to have the reserve transferred to the Conservation Commission to be managed by DEC as an 'A' Class Nature Reserve.

Promote awareness
The importance of biodiversity conservation and the need for the long-term protection of wild subpopulations of this species will be promoted to the community through poster displays and the local print and electronic media.

Rehabilitate habitat as required
DEC will undertake habitat restoration if it is identified as being required during monitoring.

Landowners have been made aware of the occurrence of this species on their property. Where appropriate, road markers have been installed (WA DEC 2007).

The taxonomy for this species was originally described by Hopper and Brown (2001b).

The National Recovery Plan for Dunsborough Spider Orchid Caladenia viridescens (Patten et al. 2008) and the Declared Rare and Poorly Known Flora in the Central Forest Region - Wildlife Management Program No. 33 (Williams et al. 2001) provide brief biological and management recommendations for the Dunsborough Spider-orchid.

The following table lists known and perceived threats to this species. Threats are based on the International Union for Conservation of Nature and Natural Resources (IUCN) threat classification version 1.1.

Threat Class Threatening Species References
Agriculture and Aquaculture:Livestock Farming and Grazing:Grazing pressures and associated habitat changes National Recovery Plan for Dunsborough Spider Orchid Caladenia viridescens (Patten, J., A.P. Webb & A. Batty, 2008) [Recovery Plan].
Biological Resource Use:Gathering Terrestrial Plants:Recreational harvest National Recovery Plan for Dunsborough Spider Orchid Caladenia viridescens (Patten, J., A.P. Webb & A. Batty, 2008) [Recovery Plan].
Human Intrusions and Disturbance:Recreational Activities:Disturbance, especially from human recreational activities and development Declared Rare and Poorly Known Flora in the Central Forest Region. Part 2 (Williams, K., A. Horan, S. Wood & A. Webb, 2001) [State Species Management Plan].
Human Intrusions and Disturbance:Recreational Activities:Soil disturbance and/or trampling due to bushwalking National Recovery Plan for Dunsborough Spider Orchid Caladenia viridescens (Patten, J., A.P. Webb & A. Batty, 2008) [Recovery Plan].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or habitat degradation Oryctolagus cuniculus (Rabbit, European Rabbit) Dunsborough Spider Orchid (Caladenia viridescens ms), Interim Recovery Plan 1996-1999 (Papenfus, D., Brown, A. & Bunny, F., 1997b) [Recovery Plan].
National Recovery Plan for Dunsborough Spider Orchid Caladenia viridescens (Patten, J., A.P. Webb & A. Batty, 2008) [Recovery Plan].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or habitat degradation by weeds National Recovery Plan for Dunsborough Spider Orchid Caladenia viridescens (Patten, J., A.P. Webb & A. Batty, 2008) [Recovery Plan].
Declared Rare and Poorly Known Flora in the Central Forest Region. Part 2 (Williams, K., A. Horan, S. Wood & A. Webb, 2001) [State Species Management Plan].
Invasive and Other Problematic Species and Genes:Invasive and Other Problematic Species and Genes:Predation, competition, habitat degradation and/or spread of pathogens by introduced species Species threats data recorded on the SPRAT database between 1999-2002 (Department of Sustainability, Environment, Water, Population and Communities (DSEWPaC), 2012i) [Database].
Invasive and Other Problematic Species and Genes:Problematic Native Species:Competition, predation and/or habitat degradation by kangaroos and wallabies Species threats data recorded on the SPRAT database between 1999-2002 (Department of Sustainability, Environment, Water, Population and Communities (DSEWPaC), 2012i) [Database].
National Recovery Plan for Dunsborough Spider Orchid Caladenia viridescens (Patten, J., A.P. Webb & A. Batty, 2008) [Recovery Plan].
Natural System Modifications:Fire and Fire Suppression:Inappropriate and/or changed fire regimes (frequency, timing, intensity) Caladenia viridescensin Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage, 2006dp) [Internet].
National Recovery Plan for Dunsborough Spider Orchid Caladenia viridescens (Patten, J., A.P. Webb & A. Batty, 2008) [Recovery Plan].
Natural System Modifications:Fire and Fire Suppression:Inappropriate prescribed regimes and/or vegetation management to control fire regimes Declared Rare and Poorly Known Flora in the Central Forest Region. Part 2 (Williams, K., A. Horan, S. Wood & A. Webb, 2001) [State Species Management Plan].
Pollution:Garbage and Solid Waste:Dumping of household and industrial waste National Recovery Plan for Dunsborough Spider Orchid Caladenia viridescens (Patten, J., A.P. Webb & A. Batty, 2008) [Recovery Plan].
Species Stresses:Indirect Species Effects:Low numbers of individuals Declared Rare and Poorly Known Flora in the Central Forest Region. Part 2 (Williams, K., A. Horan, S. Wood & A. Webb, 2001) [State Species Management Plan].
Species Stresses:Indirect Species Effects:Poor recruitment (regeneration) and declining population numbers National Recovery Plan for Dunsborough Spider Orchid Caladenia viridescens (Patten, J., A.P. Webb & A. Batty, 2008) [Recovery Plan].
Transportation and Service Corridors:Roads and Railroads:Development and/or maintenance of roads National Recovery Plan for Dunsborough Spider Orchid Caladenia viridescens (Patten, J., A.P. Webb & A. Batty, 2008) [Recovery Plan].

Brown, A., C. Thomson-Dans & N. Marchant, eds. (1998). Western Australia's Threatened Flora. Como, Western Australia: Department of Conservation and Land Management.

Hoffman, N. & A. Brown (1992). Orchids of South-west Australia 2nd edn. Nedlands, Western Australia: University of Western Australia Press.

Hopper, S.D. & A.P. Brown (2001b). Contributions to Western Australian orchidology: 2. New taxa and circumscriptions in Caladenia (Spider, Fairy and Dragon Orchids of Western Australia). Nuytsia. 14(1/2):27-314. Perth, Western Australia: Department of Conservation & Land Management.

Papenfus, D., Brown, A. & Bunny, F. (1997b). Dunsborough Spider Orchid (Caladenia viridescens ms), Interim Recovery Plan 1996-1999. Waneroo: WA CALM.

Western Australia Department of Environment and Conservation (WA DEC) (2007). Records held in DEC's Declared Flora Database and rare flora files. Perth, Western Australia: Department of Environment and Conservation.

Western Australian Herbarium (n.d.). FloraBase - The Western Australian Flora. [Online]. Western Australia, Department of Conservation and Land Management. Available from: http://florabase.calm.wa.gov.au/.

Williams, K., A. Horan, S. Wood & A. Webb (2001). Declared Rare and Poorly Known Flora in the Central Forest Region. Part 2. [Online]. Western Australian Wildlife Management Program No. 33. Department of Conservation and Land Management. Available from: http://www.dpaw.wa.gov.au/plants-and-animals/threatened-species-and-communities/threatened-plants.

EPBC Act email updates can be received via the Communities for Communities newsletter and the EPBC Act newsletter.

This database is designed to provide statutory, biological and ecological information on species and ecological communities, migratory species, marine species, and species and species products subject to international trade and commercial use protected under the Environment Protection and Biodiversity Conservation Act 1999 (the EPBC Act). It has been compiled from a range of sources including listing advice, recovery plans, published literature and individual experts. While reasonable efforts have been made to ensure the accuracy of the information, no guarantee is given, nor responsibility taken, by the Commonwealth for its accuracy, currency or completeness. The Commonwealth does not accept any responsibility for any loss or damage that may be occasioned directly or indirectly through the use of, or reliance on, the information contained in this database. The information contained in this database does not necessarily represent the views of the Commonwealth. This database is not intended to be a complete source of information on the matters it deals with. Individuals and organisations should consider all the available information, including that available from other sources, in deciding whether there is a need to make a referral or apply for a permit or exemption under the EPBC Act.

Citation: Department of the Environment (2014). Caladenia viridescens in Species Profile and Threats Database, Department of the Environment, Canberra. Available from: http://www.environment.gov.au/sprat. Accessed Sat, 19 Apr 2014 02:00:45 +1000.