Indicative distribution
The areas shown in pink and/purple are the sub-regions where the species or community is known or predicted to occur. They may not occur thoughout the sub-region but may be restricted to certain areas.
(
click here to see geographic restrictions).
The information presented in this map is only indicative and may contain errors and omissions.
Scientific name: Grevillea parviflora subsp. supplicans
Gazetted date:
24 Dec 1999
Profile last updated:
30 Jul 2019
Description
A low shrub less than 1 m tall with arching branches, adopting a semi-prostrate form in exposed, shallow-soil situations. Branchlets are usually arranged on one side of the branch, with the leaves mostly held skywards. Leaves, 15 – 60 mm long, 0.6 – 2 (rarely up to 3) mm wide, are much shorter than in G. parviflora subsp. parviflora or G. linearifolia, and they are strongly curled under at the margins. Flowers usually white (though can be purple to pink) and are similar to those of G. linearifolia (with which it grows) and G. sericea; stipe of ovary 0.5 – 0.6 mm long. The species is differentiated from G. parviflora and G. linearifolia in Olde & Marriott (1995), p.80, and illustrated in fig. 58B as G. parviflora.
Distribution
Has a very restricted known distribution (approximately 8 by 10 km) and is confined to the north-west of Sydney near Arcadia and the Maroota–Marramarra Creek area, in Hornsby and Baulkham Hills local government areas. It is known from only a few locations, one of which is in the southern portion of Marramarra National Park.
Habitat and ecology
- Occurs in heathy woodland associations on skeletal sandy soils over massive sandstones. Local observations (by Douglas) do not support the description by Olde & Marriott (1995) of its habitat as "wet heath", rather that this taxon is strongly associated with clay-capped ridged of the Lucas Heights and Faulconbridge soil landscapes, but that it is quite restricted within these areas, suggesting it has a preference for yellow clays with periodically impeded drainage.
- This plant may have an affinity with disturbance margins such as trail and road verges where soils are suitable and the availability of light due to clearing has promoted its growth.
- May be associated with the margins of the Sydney Turpentine Ironbark Forest endangered ecological community and, to a greater extent, with Shale/Sandstone Transition Forest endangered ecological community.
- Regenerates from seed and possibly also suckers.
- Flowering is from August to November. Probably pollinated by insects.
Regional distribution and habitat
Click on a region below to view detailed distribution, habitat and vegetation information.
Threats
- A frequent fire regime: if the fire interval is shorter than the period between germination and seed production, recruitment to the seedbank will be limited or not occur at all and post-fire regeneration will deplete the existing seedbank. Three or more fires in close succession may therefore result in population decline or extinction.
- Road use and management, including mechanical methods for roadside vegetation management or bushfire fuel hazard reduction where populations are proximate to roads, utilities and other assets.
- Legal or illegal bush rock removal may destroy plants and degrade the habitat, as it occurs in areas where Hawkesbury sandstone outcrops.
- Rubbish dumping.
- Weed invasion including African lovegrass (Eragrostis curvula) and other persistent perennial grasses and forbs.
- With a restricted distribution and small and fragmented populations, the species is susceptible to extinction from random natural and human-induced events because of the small size and limited genetic base of its single population. Is also susceptible to reductions in the bioclimatic range caused by climate change.
- The species is potentially susceptible to phytophthora fungal disease if it is introduced to locations where it occurs.
- Uncontrolled road/power line maintenance.
- Potential for development in the sites with lack of secure tenure.
- Fragmentation and probably direct loss of habitat has occurred, and is likely to continue to occur, as a result of native vegetation clearing or modification for semi-rural and urban development expansion and agricultural and industrial activities.
- This species need more knowledge about its distribution.
Recovery strategies
Priority actions are the specific, practical things that must be done to recover a threatened species, population or ecological
community. The Office of Environment and Heritage has identified
13 priority actions
to help recover the Grevillea parviflora subsp. supplicans in New South Wales.
Activities to assist this species
- Prevent frequent fires from impacting on the populations. In the absence of more specific information a minimum fire-free interval of seven years, plus an additional three years in each of which seed production occurs, is consistent with the fire interval guidelines vegetation types in which this species occurs (NSW NPWS 2002).
- At appropriate intervals, fires of moderate to high intensity, or fires of low intensity that move slowly and fully combust a high proportion of ground fuels, should be planned and implemented to generate a level of heat suitable to break seed dormancy.
- Minimise habitat loss, fragmentation or disturbance by retaining native vegetation containing the species and maintaining connectivity between populations.
- Seek conservation agreements with land owners.
- In potential habitat, conduct surveys prior to roadside, powerline or infrastructure maintenance and weed control activities. Ensure that such activities are planned and implemented to take account of the presence of the species and to avoid damaging individual plants or degrading habitat for the species.
- Survey potential habitat for new populations.
Information sources
- Australian Biological Resources Study (2000) Flora of Australia, vol. 17A.: Proteaceae 2: Grevillea. ABRS/CSIRO, Canberra.
- NSW National Parks and Wildlife Service (2002) Fire interval guidelines for broad vegetation types. NSW National Parks & Wildlife Service. Unpublished.
- NSW Scientific Committee (1999) Grevillea parviflora subsp. supplicans (a low shrub) - Endangered species determination - final. DEC (NSW), Sydney.
- Olde, P.M. and Marriott, N.R. (1995) The Grevillea Book Vol. 3, Kangaroo Press, NSW.
|
IBRA Bioregion
|
IBRA Subregion
|
Known or predicted
|
Geographic restrictions region
|
|---|