Survey of threatened plant species in South East Queensland biogeographical region queensland cra/rfa steering committee survey of threatened plant species in
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3.16 Lasiopetalum sp. (Proston J.A. Baker 17)3.16.1 SummaryLasiopetalum sp. (Proston J.A. Baker 17) is endemic to south east Queensland and is restricted to a very small area north of Proston where it is known from four sites. The total population is estimated to be 1180 plants in an area of approximately 50 hectares. The largest population occurs on freehold land while the other three stands occur on road verges. It occurs in eucalypt open forest on red loamy soils at altitudes of approximately 500 m. A current threat to the species is the loss of habitat to agricultural development. 3.16.2 Species description and identificationThe genus Lasiopetalum is placed in the family Sterculiaceae. The genus is endemic to Australia where there are approximately 35 species distributed throughout the southern part of Australia with two species extending to south-east Queensland. Lasiopetalum sp. (Proston J.A. Baker 17) has not been formally described but has been recognised as a distinct taxon since 1994. The botanical description Lasiopetalum sp. (Proston J.A. Baker 17) is as follows: Erect shrub to 60 cm high; stems terete, densely stellate tomentose. Leaves with petioles 0.5-2 cm long; blades narrowly ovate to ovate, apex acute, base obtuse to subcordate, margin entire or almost so, 2.5-8 cm long, 0.8-3 cm wide, scattered stellate hairs above, densely stellate tomentose beneath. Inflorescences dense several-many-flowered leaf-opposed cymes, densely ferruginous tomentose; Calyx pinkish, 508 mm long, lobes narrowly ovate to ovate, stellate tomentose outside, glabrous except for margins inside, ovary densely pubescent. Fruits more or less ovoid, approximately 4 mm high, tipped by persistent style, loculicidally dehiscent (Stanley and Ross 1986) Lasiopetalum sp. (Proston J.A. Baker 17) can be distinguished from the other species of Lasiopetalum in Queensland by the colour, shape and indumentum of its calyx. These differences are set out in Table 3.16.1. Table 3.16.1. Characters distinguishing Lasiopetalum sp. (Proston J.A. Baker 17) and Lasiopetalum ferrugineum
3.16.3 Current conservation statusLasiopetalum sp. (Proston J.A. Baker 17) is presently not listed on the schedule of threatened wildlife of the Queensland Nature Conservation Act 1992 or the Commonwealth Endangered Species Act 1992. However its inclusion on the Queensland Schedule of threatened wildlife as ‘Endangered’ is currently pending. It is proposed to be added to the schedule because it has a very restricted distribution and is not in any formal conservation reserve. It is threatened by habitat loss for agriculture. 3.16.4 Distribution and abundanceDetails from Queensland Herbarium specimens of Lasiopetalum sp. (Proston J.A. Baker 17) are listed in Appendix 1.15. The species is restricted to a very small area north of Proston where it is known from four sites. There is no quantitative data available on population sizes. The following figures come from the Queensland Herbarium Rare and Threatened Database. The largest stand occurs on freehold land with an estimated population of approximately 1000 plants. The other three stands occur on road verges and are estimated to consist of 30, 50 and 100 plants. The four stands were probably remnants of a once continuous population that extended over an area approximately 4 km long but is now reduced to approximately 50 hectares of fragmented habitat. 3.16.5 HabitatLasiopetalum sp. (Proston J.A. Baker 17) has been recorded growing in eucalypt open forest on red loamy soils at altitudes of approximately 500 m. Associated species included Eucalyptus fibrosa, E. melanoleuca, E. apothalassica, Corymbia intermedia, Melaleuca groveana. 3.16.6 Life history and ecologyThere have been no studies into the biology or autecology of Lasiopetalum sp. (Proston J.A. Baker 17). The majority of the following information is extrapolated from our understanding of other species of Lasiopetalum. A number of the more common species of Lasiopetalum have been propagated by cuttings and seed. It is reported that the seed does not require any pretreatment but may take 40-90 days to germinate (Elliot and Jones 1993). Lasiopetalum sp. (Proston J.A. Baker 17) is a perennial shrub that reproduces by sexually produced seeds. There is no indication that the species can vegetatively reproduce. The longevity of the plants is unknown. Lasiopetalum sp. (Proston J.A. Baker 17) has been recorded flowering from September to November and fruiting has not been observed. However the fruit are suspected to mature soon after flowering. Pollinators are unknown but it is suspected to be insects. The seed would be released soon after maturity. There is no information about possible dispersal mechanisms. The longevity and viability of the seed is unknown. The response of Lasiopetalum sp. (Proston J.A. Baker 17) to fire is unknown and it is not known whether it has a lignotuber or similar root structures which would allow regeneration after fire. 3.16.7 ThreatsHabitat loss due to clearing for agriculture in this species’ narrow geographical range has undoubtedly led to a decline in populations in the past. Conversion of habitat to agricultural pursuits is still continuing to occur and poses a major threat to the long term survival of the species. The lack of ecological information about this species’ response to fire makes it impossible to assess how fire would impact on the long term survival of the species. 3.16.8 Management, research and conservation measuresOne of the first steps towards the protection of this species in the wild should be to protect the known populations and their habitat. The majority of the populations are on freehold land. Liaison with land owners and local authorities are required to make them aware of the presence of the species and the importance of protecting the populations from further decline. Discussions should be undertaken with the land holders in regard to protecting the areas with Conservation Agreements under the Queensland Nature Conservation Act 1992. Local authorities should be made aware of the populations on the road verge. Very little seems to be known about this species. Previously recorded sites should be examined to establish their size and extent. Areas of likely habitat in the vicinity of the known populations should be searched for further occurrences. Investigation of the ecology of Lasiopetalum sp. (Proston J.A. Baker 17) is warranted, particularly by monitoring population numbers over several years and investigating the impacts of burning and other land-use practices. |