Grevillea curviloba subsp. curviloba, also known as the Narrow Curved-leaf Grevillea, is listed as Endangered under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (EPBC) and as Declared Rare Flora under the WA Wildlife Conservation Act 1950.
The first collection of Grevillea curviloba subsp. incurva, was gathered in 1927 near Muchea. Further specimens were found near Badgingarra in 1960, and in 1992 a single plant was found at a mining rehabilitation site south of Eneabba.
Grevillea curviloba subsp. incurva is now confined to an area between Muchea and Badgingarra, and grows in open heath in winter-wet areas on sand over limestone or over ironstone at sites with a high water table.
It is associated with the ‘Shrublands and Woodlands on Perth to Gingin Ironstone’ and the ‘Shrublands and Woodlands on Muchea Limestone’ communities. These are both listed as threatened ecological communities (TECs).
Grevillea curviloba subsp. incurva grows as a vigorous, sprawling shrub to a height and width of 2.5m, and features greyish-green leaves. The leaves are 1.8-5.2 cm long, with 3-5 strongly incurved, narrowly-linear lobes.
Inflorescences occur on short stalks and usually occur in the leaf axils, while Individual flowers are creamy white. Flowering occurs from September to October.
Like many other grevilleas, the subspecies regenerates from soil-stored seed, but has been observed to re-sprout from root stock after fire or loss of foliage by other means – such as grazing and slashing. It is pollinated by insects, possibly native bees or wasps.
Grevillea curviloba subsp. incurva has been cultivated by the horticultural industry and, as it forms a dense, attractive ground cover, has been planted extensively throughout the Perth metropolitan area, particularly in rehabilitation areas.
This species is under threat from a number of causes including the severe fragmentation of populations, and a decline in the area and quality of habitat.
Weeds, accidental destruction from road, track and rail maintenance, rabbit warren construction, fire, and chemical drift have also been named as causes, while impacts of the plant pathogen Phytophthora spp. (dieback) on the habitat may also be a possible cause.
Information Source: Government of Australia, Department of Environment, and Department of Parks and Wildlife Western Australia