Endemic to SW Australia in low shrubland on sandplains. Increased frequency of fires and continued fragmentation of its habitat could result in sufficient reduction for it to qualify for listing in the future.
Description
Taxonomic Notes
Recent phylogenetic and taxonomic research suggests that the genus Actinostrobus is not distinct from Callitris (Piggin and Bruhle, 2010). This taxonomy has been adopted by the Western Australian Herbarium for the purposes of floristic work and conservation assessments. Under this taxonomy Actinostrobus acuminatus Parl. is a synonym of Callitris acuminata (Parl.) F.Muell. Currently the IUCN Redlist maintains both genera, pending a review of similar research into other groups.
Distribution
Endemic to southwestern Australia, mainly from Eneabba south to the Perth district but with a few outlying localities as far south as Argyle and Bunbury. The total extent of occurrence is estimated to be about 7,500 km2. A comparison of recent and historic herbarium specimens indicates that this species still occurs within its historic range despite losing considerable areas of its habitat to agriculture, pastoralism and urban expansion.
Habitat and Ecology
Usually a small erect or decumbent shrub in low shrubland on sandplains, often in areas subject to inundation. Occurs at low altitudes from just above sea level up to 100 m. Annual rainfall is usually less than 600 mm, mostly in the winter. Cones tend to produce few viable seeds but the ability to resprout gives it some fire resistance. are not serotinous but this and this species has little fire resistance
Human Uses
No specific uses have been recorded
Conservation Status
Global Status
Near Threatened
Global Rationale
Actinostrobus acuminatus has a relatively restricted extent of occurrence (EOO) that is within the threshold for Vulnerable (B1). Although many areas within its EOO have been converted or modified by agriculture, pastoralism or urban development, it is still relatively widespread and frequent (occurs at many more than ten locations and is not severely fragmented). An increase in fire frequencies could eventually result in sufficient decline for this species to be assessed as Vulnerable under either criteria A or B. Until then, it is assessed as Near Threatened (almost qualifies for listing under criterion B1ab(iii)).
Global threats
Increased frequency of fires and continued fragmentation of its habitat (by e.g. expanding agriculture and urban expansion) could result in sufficient reduction for it to qualify for listing in the future.
Conservation Actions
This species is not currently listed as threatened under Western Australian state legislation or as part of any threatened plant community under Australian Federal legislation. Several subpopulations occur within national parks.
References and further reading
Farjon, A. 2005. A Monograph of Cupressaceae and Sciadopitys. The Royal Botanic Gardens, Kew.
Ladd, P.G., Midgley, J.J. and Nield, A.P., 2013. Serotiny in southern hemisphere conifers. Australian Journal of Botany, 61(6), pp.486-496
Marchant, N.G. et al. 1987. Flora of the Perth Region. Department of Agriculture, Perth, Western Australia
Piggin, J. and Bruhl, J. 2010. Phylogeny reconstruction of Callitris Vent. (Cupressaceae) and its allies leads to inclusion of Actinostrobus within Callitris. Australian Journal of Botany 23: 69-93
Pye MG, Gadek PA, Edwards KJ. 2003. Divergence, diversity and species of the Australasian Callitris (Cupressaceae) and allied genera: evidence from ITS sequence data. Australian Systematic Botany 16: 505–514.