Lignicolous on rotting nikau (Rhopalostylis baueri).
On dead log
Growing on a log on the forest floor, maybe Mahoe.
Stemonitis is a distinctive genus of slime moulds found throughout the world (except Antarctica). They are characterised by the tall brown sporangia, supported on slender stalks, which grow in clusters on rotting wood. Identification within the genus is difficult, and can only be performed with confidence using a microscope.