Hylocereus megalanthus

Hylocereus megalanthus.

The Yellow Dragon fruit is possibly a hybrid of Hylocereus and Selenicereus species.
It is also known as Selenicereus megalanthus.
It is rarely grown in Australia.

They can grow on the ground or climb using aerial roots.
The narrow, 3 ribbed stems can be up to 8 m long.
The segments can be over 1 m long and the edges are slightly wavy.
The areoles have white hairs and 1 to 3 spines that are 2 to 3 mm long.

The nocturnal, funnel-shaped flowers can be almost 40 cm long.
The roughly round basal section (pericarpel) has small bracteoles under the spiny areoles.
The tepal bases are fused into the tubular hypanthium.
The outer tepal lobes are green and the inner ones are wider and white.
The many yellow stamens insert into the tube.
The style holds the greenish stigma lobes.
Flowers are self fertile.

The ovoid, yellow fruit have large tubercles.
On the top of each is a spiny areole with a small bracteole below.
The spines rub off easily.
The flesh is white and the black seeds are larger than other species.