NSW Scientific Committee - final determination
The Scientific Committee has found that:
1. Xanthosia scopulicola J.M. Hart & Henwood (family Apiaceae) is described by Hart, J.M. & Henwood, M.J. (2000) Systematics of the Xanthosia pilosa Complex (Apiaceae: Hydrocotyloideae). Australian Systematic Botany 13, 245-266. as: an ascending perennial subshrub to 20 cm high. Taproot woody with a flaky or corky surface. Plants stellately tomentose on young stems and leaves; the mature stems excorticating. Leaves grey-green, cauline, juvenile leaves trifoliolate, adult leaves simple. Petiole 2-15mm long, angular, grooved above, sheathing shortly at the base, sheaths 1-2mm long. Leaflets of the trifoliate leaves ovate, the terminal leaflet longer than the lateral leaflets, terminal leaflet 5-20mm long, 5-25mm wide, lateral leaflets 3-5mm long, 3-4mm wide, petiolulate or sessile. Simple leaves ovate, 5-20mm long, 5-25mm wide. Leaf margins flat to slightly recurved, crenate; apex obtuse. Inflorescence a compound umbel with two or three rays, 1-4 flowers per ray; flowers bisexual or rarely male. Rays terete, 2-4mm long. Involucral bracts 2 or 3, triangular, foliaceous, green, longer or shorter than the rays, 2-3mm long, c. 1mm wide, apex acute. Bracteoles 3, elliptic to obovate, petaloid, yellow, shorter or longer than flowers, 3-5mm long, 1-3mm wide, apex acuminate or obtuse. Inflorescences pedunculate; peduncles 5-25mm long. Flowers pedicellate; pedicels 1-2mm long. Sepals ovate, 1-1.2mm long, c. 0.7mm wide, green or yellow, base truncate, apex obtuse, glabrous. Petals longer than sepals, 1.0-1.2mm long, c. 0.5mm wide, white, midrib adaxially keeled and bridged with the inflexed appendage, apex obtuse, appendage smooth. Nectaries raised and prominent, c. 0.9mm high, white or yellow, hirsute. Styles 1.3-2.3mm long. Ovary hirsute. Male flowers having an undeveloped inconspicuous ovary, with the styles barely protruding above the nectaries. Fruit brown, ovate, 2.0-2.2mm long, 2.0-2.2mm wide, c. 0.5mm deep. Monocarps hirsute on the summit, elliptic in transverse section, 7-9-ribbed; ribs keeled.
2. Xanthosia scopulicola is restricted to the Jamison Valley in the Blue Mountains between Kings Tableland and the Megalong Cleft. It grows in cracks and crevices of sandstone cliff faces or on rocky outcrops above the cliffs (Hart & Henwood 2000). Small numbers of individuals grow in crevices on dry rock faces at scattered locations along the National Pass walking track and along Leura Falls Creek from Leura Cascades to the base of the escarpment (J. Smith pers comm.)
3. The total population is unknown but likely to be small due to its very restricted habitat and distribution. Most populations are within Blue Mountains National Park, though only near the boundary of the reserve.
4. Xanthosia scopulicola is threatened by track maintenance, disturbance by walkers, urban runoff and weed encroachment, and demographic and environmental stochasicity due to its small population and localised extent.
5. In view of the above the Scientific Committee is of the opinion that Xanthosia scopulicola J.M. Hart & Henwood is likely to become endangered in New South Wales unless the circumstances and factors threatening its survival or evolutionary development cease to operate.
Associate Professor Paul Adam
Chairperson
Scientific Committee
Proposed Gazettal date: 07/11/03
Exhibition period: 07/11/03 - 19/12/03