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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3.17 Leucopogon recurvisepalus C.T. White3.17.1 SummaryL. recurvisepalus occurs from north of Grafton, New South Wales to near Beerwah on the Sunshine Coast, Queensland. In Queensland, the species is known only from three sites over a range of approximately 110 km, encompassing an area of occurrence of approximately 1800 km2. Two of the three sites are within conservation reserves. It grows in hilly terrain on hillcrests or very gently to very steeply inclined hillslopes at elevations between 60 and 500 m above sea level and varying aspects. The soils are black light sandy clay loams to light clays on sandstones to brown to pale yellow clay loams and light clays developed from igneous rocks. The common feature of the sites is the pH of the surface soils ranging from 4.3 to 4.9. The vegetation community in which L. recurvisepalus is found varies in structure from low to tall closed heathland to mid-tall to tall woodland. Potential threats arise from inappropriate fire regimes and physical disturbance on freehold land. 3.17.2 Species description and identificationThe genus Leucopogon is placed in the family Epacridaceae. Leucopogon occurs in Australia, Malesia, Indo-China, Pacific and New Zealand, but is predominantly an Australian genus with approximately 200 of the 230 species endemic to the continent (Powell 1992). Approximately 22 species occur in Queensland. Leucopogon recurvisepalus was formally described in 1944 and based on material collected from the Plunkett area, approximately 40 km south of Brisbane (White 1944). A botanical description of Leucopogon recurvisepalus is as follows: Erect to spreading shrub to 110 cm high with villous branchlets. Leaves linear-oblong to very narrowly triangular, 4.0-8.5 mm long, 1.0-2.0 mm wide, apex acuminate, base truncate, margins recurved, minutely toothed; lamina more or less discolorous, upper surface convex, scabrous, lower surface slightly ribbed to grooved, often shortly pubescent, petiole 0.3-0.4 mm long. Inflorescences of 1 plus rudiment, 2 or 3 flowered dense axillary spikes; rhachis up to 1.5 mm long; bracteoles 1.2-1.5 mm long, broadly ovate. Flowers erect; sepals very narrowly ovate, apex attenuate, recurved abruptly 0.5-1.0 mm from tip, villous outside; corolla white, tube 2-2.5 mm long, lobes c. 2.5 mm long, densely bearded on lobes. Fruit ellipsoid, 2.8-3.2 mm long, ribbed, glabrous, brown (Powell 1992). (see Plate 7) L. recurvisepalus is closely related to and resembles the species L. ericoides but can be distinguished by its recurved sepals. They also differ in habitat with L. recurvisepalus occurring on sandstone ridges and stony hills while L. ericoides occurs on coastal sandy flats and offshore islands. 3.17.3 Current conservation statusLeucopogon recurvisepalus is currently listed on the schedule of the Queensland Nature Conservation Act 1992 as “endangered wildlife”. The species has not been assigned a national conservation status by ANZECC (1993) or listed on Schedules of the Commonwealth Endangered Species Protection Act 1992. 3.17.4 Distribution and abundanceDetails from Queensland Herbarium specimens of L. recurvisepalus are listed in Appendix 1.16. Altogether 9 specimens have been collected from three sites in south east Queensland. The original material was collected from the Plunkett area south west of Beenleigh from 1923 to 1930. In 1968 it was collected from Coochin Hills west of Beerwah and in 1995 from the D’Aguilar Range west of Mt Mee. L. recurvisepalus is also known to occur north of Grafton in northern New South Wales (Powell 1992). The Queensland distribution of L. recurvisepalus has a range of approximately 110 km and encompasses an area of occurrence of approximately 1800 km2. During the current study all three known sites were examined and it was observed that L. recurvisepalus was still present at all three. As far as can be ascertained, these three disjunct sites represent the natural distribution pattern in Queensland of this species and it is not related to habitat reduction or fragmentation from recent human activity. Appendix 2.4 gives a list of sites examined in the present survey, with locality and habitat data for those sites. At the Plunkett locality L. recurvisepalus was found to be locally common at a number of sites throughout the Plunkett Conservation Park. The park has recently incorporated a part of TR 766 (Fty 1420) which contained the largest proportion of the population in the Plunkett area. Two sites within the Plunkett Conservation Park were examined in detail. L. recurvisepalus extends outside the park onto adjacent freehold land to the west and a powerline corridor to the south of the conservation park. Potential habitat on freehold to the east of the conservation park has recently been cleared. Land to the west of the conservation park is presently mostly under pine plantation except for a small proportion of hilly terrain adjacent to the park. This land is partly freehold and partly State Forest land. The area still retains its natural vegetation and L. recurvisepalus has been observed to be present. At the Mt Coochin locality, the population was located on the slopes of the more easterly of the two peaks within the National Park. The Mt Mee locality is completely within the State Forest area (SF 893 Fty 1532). Three populations were located of which two were sampled. The populations in the Mt Mee locality are not in areas of high commercial timber values. The populations at all sites except for site 1 at Mt Mee were estimated using 50 random 1 m2 quadrats along a 100 m transect through the population. Table 3.17.1 presents the estimates of the area occupancy and abundance of L. recurvisepalus at each site examined. The total population of L. recurvisepalus was estimated with 95% confidence to be between 20000 and 1100000 individuals. Although the estimations are of limited value, it can be seen that L. recurvisepalus is presently very common where it occurs. Approximately half (42 %) of the estimated population is within conservation reserves with the remainder in a state forest area. Table 3.17.1. Estimated Abundance, area of occupancy and land tenure for Leucopogon recurvisepalus sites in Queensland surveyed in 1997. Where abundance was estimated by random transect sampling a mean value and lower and upper 95% confidence limits are given. Direct counts of plants have no estimate of error associated with them.
It is difficult to obtain an understanding of the age structure of a population from a brief survey. However, measurements of plant heights to the nearest 1 cm were used as a guide to the age structure within the population . The heights were grouped into classes of 5 cm intervals. Plants that were flowering or had evidence of recent flowering were also noted. A summary of this data is presented in Figures 3.17.1 and 3.17.2. The heights range from 5 to 110 cm with the most common size class varying from site to site. There was a lack of smaller size classes in 2 of the 4 sites examined. The proportion of reproductive individuals varied between populations from 84-100%. Flowering had occurred over a wide range of size classes. The smallest size class with flowering individuals was 2.5-7.5 cm. 3.17.5 HabitatIn New South Wales L. recurvisepalus is reported to grow in dry sclerophyll forest and heath on sandy soils (Powell 1992). The three Queensland sites observed vary substantially in physical characteristics from level or very gently inclined to very steeply inclined hillslopes at elevations between 60 and 500 m above sea level and varying aspects. The soil and the underlying geology varies from black light sandy clay loams to light clays on sandstones to brown to pale yellow clay loams and light clays developed from igneous rocks. The common feature of the sites is the pH of the surface soils ranging from 4.3 to 4.9. The vegetation community in which L. recurvisepalus is found varies in structure and floristics from low to tall closed heathland (Plate 8) dominated by Calytrix tetragona, Leptospermum microcarpum and Ptilothrix deusta to mid-tall to tall woodland with mid-dense, low to tall shrub layer and mid-dense ground layers (Plate 9). The tree species present in the woodland communities include: Mt Mee sites 1 & 2, Eucalyptus racemosa and Corymbia gummifera; Mt Coochin, C. trachyphloia, L. trinervium, E. curtisii and E. tindaliae; Plunkett site 1, E. planchoniana and Angophora woodsiana. All sites are relatively undisturbed and there is a noticeable absence of exotic weed species at all sites. Figure 3.17.1: size class distribution of leucopogon recurvisepalus population at Plunkett sites 1 and 2. 
Figure 3.17.2: size class distribution of leucopogon recurvisepalus population at mt coochin and Mt Mee site 2. 
3.17.6 Life history and ecologyLeucopogon recurvisepalus is a perennial shrub up to 110 cm high. The longevity of individual plants is unknown. The main method of reproduction is by sexually produced seeds. The bisexual flowers have been reported from June to July in New South Wales (Powell 1992). In Queensland flowering has been observed in January, March, April, June, August and September. It would appear that L. recurvisepalus may flower at most times of the year, but the principal flowering season is during August-September. The flowers are small and white. Although no pollinators have been reported or observed it is suspected to be insect pollinated. Each inflorescence has 1, 2 or 3 flowers each with the potential of producing seed. Although the ovary is 5-celled with 1 ovule per cell only single seeded fruit have been observed. The fruits form soon after flowering. The fruit fall from the plant soon after maturing. There does not appear to be any attractant to facilitate animal dispersal. Nothing is known about the germination and viability of seeds. It is believed that the seeds are in a dormant state and there would be an accumulation of seed in the soil. The response of L. recurvisepalus to fire is unknown but it is believed that above-ground parts are fire-sensitive and are killed by fire. Whether the plants are capable of regenerating from rootstock is unknown. It appeared from field observation that the species is not capable of resprouting from the stem base and is dependent on seedling recruitment for its continued existence after fire. 3.17.7 ThreatsThere appears to be no immediate threats evident to those populations within the areas reserved for conservation or those populations on State Forest areas. The populations that occur on freehold land around Plunkett Conservation Park are threatened by land clearing. A potential threat to L. recurvisepalus would be the application of an inappropriate fire regime to the populations. The lack of knowledge of the species’ response to management tools such as fire may lead to the application of a fire regime that is detrimental to the long term survival of the species. The species’ response to fire needs to be understood in the long term if successful management techniques are to be developed for the conservation of the species in the wild. 3.17.8 Management, Research and Conservation MeasuresFor the populations within the conservation reserves and state forest lands appropriate management practices need to be put into place to ensure the long-term survival of L. recurvisepalus in the wild. However, at present there is a lack of ecological information about L. recurvisepalus which makes it impossible to assess what would be appropriate for the management of the habitat for the long term benefit of the species. Research needs to be undertaken to understand the exact role of fire in the ecology of L. recurvisepalus. For those populations that extend outside the conservation reserve at Plunkett, liaison with land owners and local authorities should be undertaken to make them aware of the presence of the species and the importance of protecting the populations. Discussions should be undertaken with the land holders in regard to protecting the areas with Conservation Agreements under the Queensland Nature Conservation Act 1992. When assessed against the IUCN (1994) criteria for threatened wildlife L. recurvisepalus falls into the category of Vulnerable, ie. is facing a high risk of extinction in the wild in the medium-term future, as defined by criteria D.2. Its population is characterised by an acute restriction in its area of occupancy (typically less than 100 km2) or in the number of locations (typically less than 5). |