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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3.9 Clematis fawcettii F. Muell.3.9.1 SummaryClematis fawcettii is restricted to south-eastern Queensland and north-eastern New South Wales where it occurs from the Richmond River north to the Bunya Mountains in mostly closed forest communities on loam soils derived from basalts and mixed volcanic rocks at altitudes above 500 m. There is currently no data on population sizes. However the species is generally observed to be at low densities within the community in which it grows. Potential threats to the survival of the species are weed invasion of the habitat and an inappropriate fire regime. 3.9.2 Species description and identificationThe genus Clematis is placed in the family Ranunculaceae and is cosmopolitan with approximately 295 species chiefly in the temperate regions of the world (Mabberley 1997). There are 10 species presently recognised in Australia. Clematis fawcettii F. Muell. was formally described in 1876 from material collected near Lismore, northern New South Wales (Mueller 1876). The botanical description of Clematis fawcettii is as follows: Weak climber with stems 1-2 m long, dioecious. Leaves biternately or triternately divided or if ternate then with the ultimate segments strongly lobed or toothed; petioles 2-6 cm long, petiolules 2-5 mm long; leaflet blades ovate, apex acute, base cuneate, margin more or less serrate and deeply lobed 0.6-4 cm x 0.5-3 cm, often more or less pubescent. Sepals white becoming pinky-mauve with age, narrowly lanceolate, apex acute, 0.8-2.5 cm long, more or less pubescent outside; stamens with filaments 2-6 mm long, anthers 0.7-1 mm long, without appendages; ovary puberulent. Achenes approximately 4 mm long, slender, awn 2-2.5 cm long (Stanley & Ross 1983, Briggs & Makinson 1990). For an illustration see Briggs and Makinson (1990). Clematis fawcettii is distinguished from other Clematis species in the region by having biternately or triternately divided leaves or if ternately divided then the ultimate segments are strongly lobed or toothed, ultimate leaflets 3-75 mm wide, strongly reflexed sepals in male flowers and very narrow-ovate achenes less than 1 mm wide. 3.9.3 Current conservation statusClematis fawcettii 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. 3.9.4 Distribution and abundanceC. fawcettii is restricted to south-eastern Queensland and north-eastern New South Wales where it occurs from the Richmond River north to the Bunya Mountains. C. fawcettii was not surveyed during the present study. Details from Queensland Herbarium specimens of C. fawcettii are listed in Appendix 1.8. Collections have been made in the Tweed Range, New South Wales, McPherson and Great Dividing Ranges, and the Bunya Mountains in Queensland. There are records from Lamington National Park and from SF 151 Fty 824 while other possible sites are in the Main Range and Mt Barney National Parks and SF 750 Fty 1605, SF 327 Fty 1502, SF 401 Fty 1186, SF 661 Fty 1187, SF 735 Fty 1187 and SF 510 Fty 1416. There is no information available on population sizes. C. fawcettii is usually reported as having only isolated or a few individuals at the collection sites. Observations indicate that it prefers to grow in small canopy gaps (W. McDonald pers. comm.). 3.9.5 HabitatC. fawcettii has been reported growing on slopes at altitudes above 500 m in complex notophyll vineforest (warm and cool subtropical rainforest), on the margins of semi-evergreen vine thickets and at one site, in eucalypt open forest with scattered vine forest species. The species has been recorded on brown to chocolate loam soils derived from basalt and mixed acidic and volcanic rocks. Barry and Thomas (1994) noted C. fawcettii was usually found near streams in drier rainforests habitats. 3.9.6 Life history and ecologyC. fawcettii is a dioecious perennial, weak climber. The main method of reproduction is sexually produced seeds. It has been recorded flowering from October to December and fruiting in January, June and December. There is no information available about the viability or longevity of the seed. Elliott and Jones (1994) reported that seed of Clematis species is often difficult to germinate and that higher levels of germination are achieved with fresh seed. A single individual of Clematis fawcettii propagated from seed has been grown for 11 years (L. Bird pers. comm.). The plant continues to grow and flower every year. Another species of Clematis (C. glycinoides) has been found to be easily propagated from cuttings (K. Hall pers. comm.). There is no information on the response of adult plants to fire. However, C. fawcettii is suspected to be fire-sensitive and killed by fire. There is no evidence to suggest that it is capable of regenerating from the rootstock. Therefore, regeneration after fire would rely on the successful germination of seed and survival of seedlings. 3.9.7 ThreatsThe sites on rainforest margins may be susceptible to the invasion of exotic weed species such as lantana (Lantana camara) (W. McDonald pers. comm.). Weeds such as mist flower (Ageratina riparia) and crofton weed (Ageratina adenophora) may pose a threat to this species along creeks and canopy gaps within the rainforest communities. Fire may be a threat to those populations on the rainforest margins and in eucalypt open forest. However, the lack of information about the species’ response to fire makes it difficult to assess whether fire would be a significant threat. 3.9.8 Management, research and conservation measuresLittle information appears to be available about this species. Detailed surveys are needed to assess previously recorded localities and to collect information on habitat requirements. There is little information available on the ecology and reproductive biology of Clematis fawcettii. The response of this species to disturbance and fire should be thoroughly investigated. |