About Austrocallerya megasperma (F.Muell.) J.Compton & Schrire
Austrocallerya megasperma is a woody climbing vine with stems that reach up to 20 metres (66 feet) in length, and its stems are covered in flaky bark. Its leaves are 15–30 centimetres (5.9–11.8 inches) long, pinnately compound, and carry 7 to 19 leaflets. The leaflets are oblong to egg-shaped, with the narrower end at the base, and measure 4–10 centimetres (1.6–3.9 inches) long by 2–3.5 centimetres (0.79–1.38 inches) wide. The entire leaf is borne on a petiole 4–6 centimetres (1.6–2.4 inches) long. Flowers are arranged in racemes 100–250 millimetres (3.9–9.8 inches) long, with each individual flower held on a pedicel 10–20 millimetres (0.39–0.79 inches) long. The sepals are 3–5 millimetres (0.12–0.20 inches) long, and the petals are 15–20 millimetres (0.59–0.79 inches) long. Flowering takes place from July to October. The fruit is a woody, velvety pod that measures 100–180 millimetres (3.9–7.1 inches) long and 30–50 millimetres (1.2–2.0 inches) wide, containing up to four more or less oval seeds.
This species grows in rainforest on coastal areas and nearby inland ranges of south-eastern Queensland and north-eastern New South Wales, with its range extending south as far as the Richmond River.
In ecological terms, this vine acts as a valuable indicator species, because it often grows alongside Aristolochia praevenosa, the birdwing butterfly vine. Aristolochia praevenosa is one of the only food plants for caterpillars of the rare Richmond birdwing butterfly, Ornithoptera richmondia. Austrocallerya megasperma itself serves as a food plant for the caterpillars of two other butterfly species: the pencilled blue (Candalides absimilis) and the narrow-banded awl (Hasora khoda).
Commonly called native wisteria, this species is grown in horticulture as an attractive garden plant. However, it grows very quickly when young, requires plenty of space to develop, and needs a sturdy structure capable of supporting its weight. It also requires well-drained growing conditions. It has been successfully cultivated in Melbourne, where cultivated individuals took 20 years to produce their first flowers.
