Hypocalymma longifolium, Long-leaved myrtle, is listed as Vulnerable under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and Vulnerable under the Wildlife Conservation Act 1950.
Potential threats include grazing and trampling by feral pigs and goats, which have been observed to be present where the species occurs.
While grazing on this species has not been observed, the impact that feral species may have on the surrounding habitat is a threat to the long-leaved myrtle. An additional potential threat to the species may be inappropriate fire regimes, as the species’ response to fire is uncertain.
Hypocalymma longifolium, family Myrtaceae, also known as the long-leaved myrtle, is a low hairless shrub, up to 20 cm tall, with rigid erect branches and pale pink to white flowers that have five petals. The leaves are held in opposite pairs and are 4–6 cm long, linear and triangular in cross-section, and taper to a slightly recurved point. The flowers are stalkless and are in pairs held on a short, thick inflorescence stalk.
The long-leaved myrtle is endemic to Western Australia, where it is known from one location near the Murchison River. It occurs in damp areas on the west-facing slopes of breakaways and grows amongst open, low scrub on white sand with sandstone. The species’ area of occupancy is estimated to be 0.25 km2.
The long-leaved myrtle is associated with Melaleuca uncinata, M. filifolia, Lechenaultia chlorantha and Acacia species. The known number of mature individuals has increased since 1992, with an estimated 500+ plants found at the site in November 2009. It is expected that this number will increase with further surveying.
The distribution of this species is not known to overlap with any EPBC Act-listed threatened ecological community.
Research priorities that would inform future regional and local priority actions include:
- Undertake seed germination and/or vegetative propagation trials to determine the requirements for successful establishment.
- Continue to monitor population size and distribution at the one known location.
- Undertake survey work in suitable habitat and potential habitat to locate any additional populations.
- Identify the appropriate intensity and/or interval of fire to promote seed germination and vegetation regeneration.
- Assess ecological requirements and the relative impacts of threatening processes, including inappropriate fire regimes.
Information Source: Government of Australia, Department of Environment and Department of Parks and Wildlife Western Australia.