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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3.23 notelaea lloydii guymer3.23.1 SummaryNotelaea lloydii is endemic to south east Queensland where it occurs from Mt Brisbane, near Somerset Dam to just south of Beaudesert. The distribution of N. lloydii has a range of approximately 120 km and encompasses an area of occurrence approximately 3700 km2. It is recorded from one National Park (Moogerah Peaks) and from two State Forest areas (SF 494 Fty 1309 and SF 637 Fty 1613). The is no quantitative data on population size. It is most commonly found in open eucalypt forest near the margins of vine thickets, vine forests and softwood scrubs on gentle to steep dry slopes, rarely on rocky outcrops. The soils are generally well drained, shallow, stony to very rocky in texture and derived from sandstone or acid volcanic rocks. Current or perceived threats to the continued survival of N. lloydii in the wild are the loss of habitat through urban development, inappropriate fire regimes and invasion of the exotic species Lantana camara (lantana). 3.23.2 Species description and identificationThe genus Notelaea is placed in the Olive family (Oleaceae). Notelaea is endemic to Australia where there are approximately 9 species distributed throughout eastern Australia. Notelaea lloydii Guymer was formally described in 1987 from material collected by Mr L. Bird from Mt Crosby, a western suburb of Brisbane. The botanical description of Notelaea lloydii is as follows: Shrub to 4 m high with many stems arising from the base. The stems are covered with a smooth, pale grey bark. The hairless, discolorous, leathery leaves are linear or slightly falcate, 7-14 cm long, 2-5.5 mm wide, and arranged in opposite pairs along the branchlets. The main leaf veins are clearly visible and slightly raised on the upper leaf surface. Flowers are pale yellow or cream, up to 2 mm in diameter and grow on slender stalks 3-5 mm long. Up to 20 flowers may be grouped together on a stem that grows from the joint of a leaf with a branchlet, The fruits are spherical to ovoid, 6-8 mm long, 5-8 mm in diameter, and consist of a hard woody nut with a thin, dark blue skin. For a more detailed description of this species refer to (Guymer 1987). Illustrations of this species are published in Williams (1987) and Guymer (1987). N. lloydii may be confused with the closely related N. microcarpa but can be distinguished by its leaf shape and habit (W. Harris pers. comm.). The differences are set out in Table 3.23.1. Table 3.23.1. Characters distinguishing Notelaea lloydii and Notelaea microcarpa
3.23.3 Current conservation statusNotelaea lloydii is presently listed on the schedule of the Queensland Nature Conservation Act 1992 as “vulnerable wildlife”. The species has been assigned a national conservation status of V (vulnerable) by ANZECC (1993). It is also listed on Schedule 1 Part 2 (vulnerable) of the Commonwealth Endangered Species Protection Act 1992. 3.23.4 Distribution and abundanceNotelaea lloydii was not surveyed during the present study. Details from Queensland Herbarium specimens of N. lloydii are listed in Appendix 1.22. The species is known from thirty five collections. Notelaea lloydii has a distribution from Mt Brisbane, near Somerset Dam to just south of Beaudesert. Twenty three of the collections have been made either on private land or road sides within the western suburbs of Brisbane and Ipswich. It is recorded from one National Park (Moogerah Peaks) and from two State Forest areas (SF 494 Fty 1309 and SF 637 Fty 1613). There is no quantitative data available on population sizes, however, it has been reported as being rare or only a few plants seen at collection sites. The distribution of Notelaea lloydii has a range of approximately 120 km and encompasses an area of occurrence of approximately 3700 km2. 3.23.5 HabitatNotelaea lloydii is most commonly found in open eucalypt forest near the margins of vine thickets, vine forests and softwood scrubs at altitudes of 80 to 480 m. It occurs in undulating to hilly terrain on gentle to steep dry slopes, rarely on rocky outcrops. The soils are generally well drained, shallow, stony to very rocky in texture and derived from sandstone or acid volcanic rocks. The more frequent tree species recorded with this species are Eucalyptus crebra, Corymbia citriodora, E. acmenoides and Acacia concurrens. Other associated trees and shrubs are Brachychiton populneus, Alphitonia excelsa, Acacia aulacocarpa, A. falcata and Diospyros geminata. 3.23.6 Life history and ecologyThere have been no studies into the biology or autecology of N. lloydii. N. lloydii 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. The species has a underground lignotuber to which the plant may die back in times of drought or fire (W. Harris pers. comm.). N. lloydii has been recorded flowering from June to August and fruiting from October to December. Insects are suspected to be possible pollinators. The fruits of N. lloydii are 5-8 mm in diameter with a single seed enclosed in a hard woody nut with a thin dark blue skin. There is no mechanical mechanism for dispersal and no dispersal agents have been recorded. It is suggested that dispersal may be effected by animals, such as birds. The longevity and viability of the seed is unknown. However, the best level of germination is achieved from fresh seed which germinates rapidly without any pretreatment (K. Hall pers. comm.). This suggests that the species would not support a long term seed bank in the soil. The above-ground structures of N. lloydii are killed by fire. However, regeneration can occur from the lignotuber. It is suspected that seeds and the early stages of the seedling development are fire-sensitive. The time required before the seedling can tolerate fire is unknown. It has been estimated that a period of least 5 years between fires would be required to allow seed to germinate and reach a stage tolerant of fire (W. Harris pers. comm.). 3.23.7 ThreatsThere can be no doubt that habitat loss due to clearing, for urban and mining in this species geographical range has led to a decline in populations in the past. The conversion of habitat to urban developments is still continuing to occur and poses a major threat to the long term survival of the species in some areas. Mature N. lloydii plants generally cope with fire. However, fire can certainly affect the recruitment of new individuals because the seeds and young seedlings of N. lloydii are appear to be fire-sensitive. Too frequent a fire regime would certainly lead to a gradual decline in the population as mature plants became senescent and there was a lack of recruitment of new plants. The populations on vine forest margins may be susceptible to the invasion of exotic weed species such as lantana (Lantana camara) into the habitat. It is suspected that lantana could modify the habitat by decreasing light intensities and increasing fire intensities to the extent that N. lloydii could not survive. 3.23.8 Management, research and conservation measuresField investigations are required to determine what populations remain and what would be the appropriate course of action for conserving the species. Areas of likely habitat in the vicinity of the known populations should be searched for further occurrences of the species. There is little information available on the role of fire in the ecology and reproductive biology of N. lloydii. This needs to be understood if successful management techniques are to be developed for conservation of the species in the wild. Research into the effect of fire on mature plants and seedlings is required. Monitoring and control of the spread of weeds in the vicinity of populations should be undertaken. For those populations that occur on freehold land and road verges, 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. |