Tetrastigma petraeum Jackes

Jackes, B.R. (1989) Austrobaileya 3(1): 153. Type: Queensland, Walleroo Hill, Herbert River, 18 08 S, 145 20 E, 30 March 1980, E. M. Jackes; holo: BRI; iso: CANB, L, NSW.

Vine stem diameters to 5 cm recorded.

Leaflet blades about 4.5-9 x 3-6.5 cm, the middle leaflet usually slightly larger than the lateral leaflets. Leaflet stalks about 5-20 mm long, the stalk of the middle leaflet usually longer than those of the lateral leaflets. Lateral veins about 4-7 on each side of the midrib. Stipules broad based, about 2-4 mm long. Tendrils simple (unbranched) leaf-opposed, often with a few thickened gland-like structures at the apex. Teeth usually 4 or 5 on each side of the leaflet blade.

Female flowers: Calyx lobes nil, not developed. Petals about 2.5 mm long, hooked or hooded at the apex. Outer surface clothed in short hairs or papillae. Stigma terminal, 4-part, cross-like.

Fruits depressed globular, about 8 x 14-16 mm, flesh about 3-5 mm thick. Seeds globose, about 9 x 6 mm diam. Testa with two longitudinal grooves on the convex side. Testa intruding into the endosperm from the flat side. Embryo about 2 mm long. Cotyledons wider than the radicle.

Cotyledons ovate to cordate, about 37 x 30-32 mm. First pair of true leaves usually simple but the second true leaf may sometimes be bifoliolate or trifoliolate. At the tenth leaf stage: leaflets ovate to elliptic, apex acuminate, base cuneate to obtuse. Margins with 3-5 teeth along each side. Midrib raised on the upper surface. Lateral veins 3-5 on each side of the midrib. Taproot thick and swollen, somewhat carrot-like. Seed germination time 119 days.

Endemic to Queensland, occurs in NEQ and CEQ. Altitudinal range from 400-800 m. Usually grows in rocky situations in open forest, vine thicket or monsoon forest.