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 Critically Endangered
Listing and Conservation Advices Commonwealth Conservation Advice on Keraudrenia exastia (Fringed Keraudrenia) (Threatened Species Scientific Committee (TSSC), 2009bt) [Conservation Advice].
 
Commonwealth Listing Advice on Keraudrenia exastia (Fringed Keraudrenia) (Threatened Species Scientific Committee (TSSC), 2009bu) [Listing Advice].
 
Recovery Plan Decision Recovery Plan not required, a recovery plan will have limited benefit for the species. The actions covered by the conservation advice are considered to be sufficient at this time (10/12/2009).
 
Adopted/Made Recovery Plans
Federal Register of
    Legislative Instruments
Inclusion of species in the list of threatened species under section 178 of the Environment Protection and Biodiversity Conservation Act 1999 (89) (10/12/2009) (Commonwealth of Australia, 2009b) [Legislative Instrument].
 
State Listing Status
WA: Listed as Critically Endangered (Wildlife Conservation Act 1950 (Western Australia): September 2013 list)
Scientific name Keraudrenia exastia [66301]
Family Sterculiaceae:Malvales:Magnoliopsida:Magnoliophyta:Plantae
Species author C.F.Wilkins
Infraspecies author  
Reference Wilkins, C.F. (1999) Keraudrenia exastia and Keraudrenia katatona (Malvaceae: Byttnerioideae), new species from the Kimberley region of Western Australia. Nuytsia 13(1): 235, Figs. 1-3 [tax. nov.]
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

Scientific name: Keraudrenia exastia

Common name: Fringed Keraudrenia

The species is conventionally accepted as Keraudrenia exastia (Wilkins 1999).

The Fringed Keraudrenia is an erect, compact, multi-stemmed shrub that can grow to 0.9 m high (Western Australian Herbarium 2006). The leaves are grey-green and oblong. The leaf stalk is 3–6 mm long and the blade 15–20 mm long. Inflorescences contain 7–9 flowers. The flowers are purple, the lobes ovate and 9–12 mm, and the flowering period is from April to December (Western Australian Herbarium 2006; Wilkins 1999).

The Fringed Keraudrenia is endemic to Western Australia, and is known from seven subpopulations within the Port of Broome, in Broome, Western Australia (WA DEC 2006). The species occurs within the Dampierland Interim Biogeographic Regionalisation for Australia Bioregion and the Rangelands Natural Resource Management region (TSSC 2009bu). The Fringed Keraudrenia is considered to have a very restricted geographic distribution. The area of occupancy of the species is approximately 0.04 km² (Broome Botanical Society 1995). While the species' geographic distribution is not considered to be fragmented, as it consists of seven subpopulations within the one location, a road divides the subpopulations into two groups and may act as a barrier to the movement of pollination vectors between them, reducing the possibility of seed set (Trudgen 1998). The species occurs on Crown Land, managed by the Broome Port Authority (WA DEC 2006).The seven subpopulations of the Fringed Keraudrenia do not occur on protected or reserved land, nor are they protected under any conservation covenants with landholders (TSSC 2009bu).

In 2012, a second population was discovered approximately 130 km south of Broome in the Great Sandy Desert area (FloraBase 2012).

In July 2006, a survey of the Fringed Keraudrenia was undertaken by the Western Australian Department of Environment and Conservation. This survey found that the species still exists at this location, but an attempt to count the number of plants was not made. The survey did support the view that the Fringed Keraudrenia is clonal and what previously appeared to be individual plants are in fact clusters of stems arising from lateral roots. Further research is required to determine the number of genetically distinct individuals (WA DEC 2009a).

The total population size of the Fringed Keraudrenia is not conclusively known. A 1995 survey estimated the total population size of the species to be 3360 mature individuals (Broome Botanical Society 1995). However, Trudgen (1998) indicated that no methodology was provided in this 1995 survey as to what was considered to be an individual, and stated that it is likely the actual population of the Fringed Keraudrenia is much smaller than the numbers counted, as much of the population is likely to consist of clones. Trudgen (1998) suggested that the number of distinct individuals may be as few as 300.

The Fringed Keraudrenia grows in pindan (red soil) heathland (Western Australian Herbarium 2006). Apart from one subpopulation which occupies a north-facing dune slope, the remaining six subpopulations occur on almost flat land and associated vegetation includes Feathertop Spinifex (Triodia schinzii) and scattered trees, under 7 m in height, of Soap Wattle (Acacia colei), Bloodwood (Eucalyptus dampieri) and several other common species with a variety of intermediate sized shrubs (Broome Botanical Society 1995).

The Fringed Keraudrenia has not been observed to set fruit (WA DEC 2006). This may mean that the species is sterile, or it may mean that fruit only sets in particularly good seasons, or that fruit production is extremely low (i.e. fruit does set, but so infrequently as to not have been observed) (TSSC 2009bu).

It has been suggested that the species may consist of one or a few large clones of self sterile (i.e. unable to self-fertilise) individuals (Trudgen 1998), that reproduce only by underground suckers (i.e. vegetatively) (Broome Botanical Society 1995). If the Fringed Keraudrenia is clonal, what were previously considered to be individual plants are likely to be clusters of stems arising from underground lateral roots from one or a few plants (WA DEC 2009a).

The Fringed Keraudrenia is closely related to Keraudrenia velutina, but differs in its shorter mature pedicels (4–9 mm long compared with 5–15 mm) and calyx lobes which are longer than they are wide (in contrast to wider than they are long or nearly the same width as length for K. velutina) (Wilkins 1999).

The main identified threats to the Fringed Keraudrenia are road maintenance works (WA DEC 2006) and competition from weeds (Broome Botanical Society 1995).

Road maintenance
All seven subpopulations occur on or close to a road verge, and are particularly vulnerable to road widening and maintenance works, such as grading and clearing, and soil compaction by vehicle movement (TSSC 2009bu).

Weeds
Weeds, including Birdwood Grass (Cenchrus setiger) and Kapok Bush (Aerva javanica), are known to have established adjacent to one of the subpopulations (Broome Botanical Society 1995). Both weed species have a well documented history of being invasive ecological weeds, and could spread into adjacent subpopulations and out-compete the Fringed Keraudrenia for resources (Broome Botanical Society 1995). Weeds suppress early plant growth by competing for soil moisture, nutrients and light. They also increase the fire hazard due to the easy ignition of high fuel loads, which are produced annually by many weed species (TSSC 2009bu).

In September 2007, a Western Australian Botanic Gardens and Parks Authority officer noted that the species is also under threat from an outbreak of native Dodder Vine (Cassytha sp.) which is smothering the Fringed Keraudrenia (WA DEC 2009a).

Development
A potential threat to the species may be the future development of the Port of Broome (Trudgen 1998). Depending on the nature of the development, this potential threat could have a direct impact (e.g. through the clearing of habitat) or an indirect impact (e.g. by affecting drainage, water availability or the introduction of pathogens) on the Fringed Keraudrenia (TSSC 2009bu).

Minister's Reasons for Recovery Plan Decision
A recovery plan is not considered to be necessary for this species as a recovery plan will have limited benefit for this species. The actions covered by the conservation advice are considered to be sufficient at this time.

The Commonwealth Conservation Advice on Keraudrenia exastia (Fringed Keraudrenia) (TSSC 2009bt) outlines the following research priorities:

  • Design and implement a monitoring program or, if appropriate, support and enhance existing programs.
  • More precisely assess population size, geographic distribution, ecological requirements, and the relevant impacts of threatening processes, including:
    • factors that influence the level of flowering, pollination and fruit development for the species
    • longevity of plants and time taken to reach maturity
    • the reproductive strategies, phenology and seasonal growth of the species
    • the species' response to disturbance (e.g. fire and slashing)
    • other relevant mortality and morphological data for the species.
  • Undertake survey work in suitable habitat and potential habitat during the April to December flowering period to locate any additional populations/occurrences/remnants.
  • Undertake vegetative propagation trials to determine the requirements for successful establishment.
  • Undertake genetic analyses to 1/ assess current gene flow (using markers and analyses capable of distinguishing population divergence on an evolutionary timescale, from that which might be due to more recent impacts), and 2/ identify populations with low genetic diversity that might benefit from artificial introduction of genetic material from other populations from which they have relatively recently diverged.

In addition, the Commonwealth Conservation Advice on Keraudrenia exastia (Fringed Keraudrenia) (TSSC 2009bt) outlines the following priority actions:

  • Monitor known populations to identify key threats.
  • Minimise adverse impacts from land use at known sites.
  • Ensure there is no disturbance in areas where the Fringed Keraudrenia occurs, excluding necessary actions to manage the conservation of the species.
  • Suitably control and manage access on private land and other land tenure.
  • Manage any disruptions to water flows.
  • Monitor the progress of recovery, including the effectiveness of management actions and the need to adapt them if necessary.
  • Develop and implement a management plan for the control of Birdwood Grass (Cenchrus setiger), Kapok Bush (Aerva javanica) and native Cassytha sp. (Dodder Vine) in the area.
  • Ensure chemicals or other mechanisms used to eradicate weeds do not have a significant adverse impact on the Fringed Keraudrenia.
  • Manage sites to prevent introduction of invasive weeds, which could become a threat to the Fringed Keraudrenia, using appropriate methods.
  • Raise awareness of the Fringed Keraudrenia within the local community through site visits, signage (e.g. roadside markers), and posters/information brochures to be distributed to local naturalist groups, relevant authorities and volunteer organisations.
  • Frequently engage with private landholders and land managers responsible for the land on which populations occur and encourage these key stakeholders to contribute to the implementation of conservation management actions.
  • Undertake appropriate collection of propagation material and storage.
  • Investigate options for linking, enhancing or establishing additional populations.
  • Implement national translocation protocols (Vallee et al. 2004) if establishing additional populations is considered necessary and feasible.

The Commonwealth Conservation Advice on Keraudrenia exastia (Fringed Keraudrenia) (TSSC 2009bt) provides a brief biological overview and management recommendations.

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
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or habitat degradation Cassytha pubescens (Hairy Devil's Twine, Hairy Dodder, Downy Dodder-laurel, Rusty Dodder-laurel, Spilled Devil's-twine, Blackfellow Twine) Commonwealth Listing Advice on Keraudrenia exastia (Fringed Keraudrenia) (Threatened Species Scientific Committee (TSSC), 2009bu) [Listing Advice].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or habitat degradation Aerva javanica (Kapok Bush) Commonwealth Listing Advice on Keraudrenia exastia (Fringed Keraudrenia) (Threatened Species Scientific Committee (TSSC), 2009bu) [Listing Advice].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or habitat degradation Cenchrus setiger (Birdwood Grass) Commonwealth Listing Advice on Keraudrenia exastia (Fringed Keraudrenia) (Threatened Species Scientific Committee (TSSC), 2009bu) [Listing Advice].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or habitat degradation by weeds Commonwealth Listing Advice on Keraudrenia exastia (Fringed Keraudrenia) (Threatened Species Scientific Committee (TSSC), 2009bu) [Listing Advice].
Residential and Commercial Development:Commercial and Industrial Areas:Recreational, commercial and industrial development Commonwealth Listing Advice on Keraudrenia exastia (Fringed Keraudrenia) (Threatened Species Scientific Committee (TSSC), 2009bu) [Listing Advice].
Transportation and Service Corridors:Roads and Railroads:Development and/or maintenance of roads Commonwealth Listing Advice on Keraudrenia exastia (Fringed Keraudrenia) (Threatened Species Scientific Committee (TSSC), 2009bu) [Listing Advice].

Broome Botanical Society (1995). Port of Broome Flora Survey, Keraudrenia species B. Unpublished report.

FloraBase (2012). Keraudrenia exastia C.F.Wilkins .

Threatened Species Scientific Committee (TSSC) (2009bt). Commonwealth Conservation Advice on Keraudrenia exastia (Fringed Keraudrenia). [Online]. Department of the Environment, Water, Heritage and the Arts. Canberra, ACT: Department of the Environment, Water, Heritage and the Arts. Available from: http://www.environment.gov.au/biodiversity/threatened/species/pubs/66301-conservation-advice.pdf.

Threatened Species Scientific Committee (TSSC) (2009bu). Commonwealth Listing Advice on Keraudrenia exastia (Fringed Keraudrenia). [Online]. Department of the Environment, Water, Heritage and the Arts. Canberra, ACT: Department of the Environment, Water, Heritage and the Arts. Available from: http://www.environment.gov.au/biodiversity/threatened/species/pubs/66301-listing-advice.pdf.

Trudgen, M. (1998). A review of the status of Keraudrenia species B with advice on an appropriate plan of management and assessment of the significance of a stand of Mangarr (Pouteria sericea) trees. Unpublished report prepared for ERM Mitchell McCotter.

Vallee, L., T. Hogbin, L. Monks, B. Makinson, M. Matthes & M. Rossetto (2004). Guidelines for the translocation of threatened plants in Australia - Second Edition. Canberra, ACT: Australian Network for Plant Conservation.

Western Australian Department of Environment and Conservation (WA DEC) (2006). Records held in DEC's Declared Flora Database and rare flora files. Perth, Western Australia: WA DEC.

Western Australian Department of Environment and Conservation (WA DEC) (2009a). Records held in DEC's Declared Flora Database and rare flora files. Perth, Western Australia: DEC.

Western Australian Herbarium (2006). Florabase - The Western Australian Flora. [Online]. Perth, Western Australia: Department of Conservation and Land Management. Available from: http://florabase.calm.wa.gov.au/.

Wilkins, C.F. (1999). Keraudrenia exastia and Keraudrenia katatona (Malvaceae: Byttnerioideae), new species from the Kimberley region of Western Australia. Nuytsia. 13 (1):233-242.

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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). Keraudrenia exastia in Species Profile and Threats Database, Department of the Environment, Canberra. Available from: http://www.environment.gov.au/sprat. Accessed Wed, 20 Aug 2014 22:53:24 +1000.