Genus Lophostemon.

In Family Myrtaceae there are 4 species that are native to Australia (one is also in PNG).
They are almost always seen as trees with some up to 50 m high.
Juvenile leaves are opposite while adult ones are alternate.
Adult leaves are so crowded at the branch ends they may appear to be in whorls.

Axillary inflorescences are small clusters with up to 8 or so flowers.
Flowers have 5 green sepal and 5 white petal lobes on the rim of a hypanthium.

The prominent feature of the flowers are the many stamens that are fused into 5 tight
    bundles inserted opposite the petals.
The half-inferior ovary has 3 locules with a single style having a small capitate stigma.

The fruit are loculicidal capsules all or mostly surrounded by the hypanthium.
The 3 chambers have many small linear seeds.

South East Queensland has 2 species L. confertus and L. sauveolens the Swamp Mahogany.
Lophostemon confertus has narrower sepal lobes, longer petals (6 mm against 3 mm) and much
    longer stamen bundles at around 10 mm compared to 3 mm for L. sauveolens.