In Family Melastomataceae there are only 4 or 5 species.

They are perennials or bushy sub-shrubs.
The often coloured stems are winged or angled.
The leaves are opposite, ovate to lanceolate.
The blades are hairy and the tips are pointed.
The veins are prominent and the underside reddish.

The small clusters of flowers are terminal or along the branches.
There is a hypanthium with 4 sepals lobes on the rim.
There are 4 pink or mauve petals.
The 8 stamens are in 2 sets of 4 – one set without the connective appendage.
There are 4 locules in the white or pink ovary.

Available in Australia and used as garden ornamentals are:

Centradenia inaequilateralis ‘Cascade’.
Centradenia ‘Spanish Shawl’.
A ground cover up to 40 cm high with unequal, opposite bronze leaves.
Flowers are a bright pink, magenta to purple.

Centradenia x inaequilateris ‘Blushing Cascade’
A fairly dense ground cover up to 0.5 m high and wide.
Stems are red and the silverey-green leaves are bronze in the cooler months.
Flowers are pink to red.

Centradenia floribunda.
Centradenia floribunda ‘Cascade Purple’ and ‘Cascade Pink’.
Dense ground covers around 30 cm high with a wide spread.
They have masses of purple or deep pink flowers respectively.

Centradenia grandiflora.
Ground cover with purple to pink flowers.

Centradenia and Heterocentron.
Some species of these genera are very similar and frequently mis-identified as each other.
Adding to the confusion is that some cultivars of Centradenia, Heterocentron and
    Dissotis are all sold a ‘Spanish Shawl’.