Mahoe tiny flowers ( Melicytus )
Possibly Melicytus macropyhllus
It is a small tree of the family Violaceae endemic to New Zealand.
Despite being a long-lived tree and having white flowers, you get a hint from the purple fruit of Mahoe that it is a member of that family, best known for the popular purple-flowered violet garden plant.
The plant is dioecious - it has male and female flowers on separate plants. . The flowers on the photo are male.
A characteristic of the the New Zealand flora is the high % of plants that have the sexes on separate plants (dioecious). Approx 12-13% of our flora are dioecious. (Britain 2-5%, South Australia , 3.9%., Hawaii 5%).
Dioeciousness is related to unspecialised pollinators as in order to avoid self pollination, that is likely to occur if many insects can effect pollination, separation of the sexes is encouraged.
Example: Coprosma, Melicytus
Location: Waitakere Ranges Regional Park, west Auckland, New Zealand
Related websites about New Zealand flora: