Family Annonaceae > Subfamily Annonioideae.
Flora of Australia Vol. 2 has it under Melodorum leichhardtii and
The Plant List site has both names as ‘unresolved’.
It is commonly known as the zigzag or knot vine.
It is a woody vine (liana) which initially grows as a bushy scrambler.
Where there is support it begins to climb when a few years old and,
in a rainforest can reach the canopy.
It is a stem twiner and the loops it forms give the appearance of knots.
Glossy green leaves are alternately arranged along the zig-zag stem.
They are elliptic to oblong with short, grooved petioles.
The blades are up to 19 cm long and 6 cm wide.
New growth is covered with minute, rust coloured stellate hairs.
This includes the twigs, petioles and the lower surface of the leaf blades.
Older leaves are smooth and shinny on both surfaces.
Flowers, on short stalks, are usually in pairs.
They appear to be leaf opposed but are actually terminal due to the manner of branching.
There are 1 or 2 bracts that are 4 mm long.
The flowers, over 2 cm wide, open in the evening.
Sepals are brown, 3 mm long and persist in the fruit.
There are usually 6 thick, fleshy, yellow-brown petals in 2 whorls.
The outer 3 are concave, broadly ovate, with hairs on the outside.
The inner 3 are slightly shorter and with a long claw at the base.
Stamens are only 2-3 mm long.
The approximately 20 carpels, 5-6 mm long, are covered in short, brown hairs.
The orange fruit, on short stalks, are up to 40 mm long.
Each has up to 5 seeds with constrictions between them.