Rhopalostylidinae


Rhopalostylidinae is a botanical subtribe consisting of two genera of palms from Australia and New Zealand, Hedyscepe and Rhopalostylis. These two genera were formerly included in Archontophoenicinae, to which they are morphologically similar, until a recent revision.

Description

The palms in this subtribe are medium-sized palms, with well-developed, distinct crownshafts and strictly pinnate leaves with generally short and massive petioles. The inflorescences are branched to two or three orders, with the prophyll and penduncular bracts similar.

Genera

The genus Rhopalostylis contains two species, R. baueri, the Norfolk palm or Niau, from Norfolk Island, Australia, and Raoul Island in the Kermadec group north of New Zealand, and R. sapida, the Nikau palm, from New Zealand. The leaves of Rhopalostylis tend to be held rigidly upright, especially in R. sapida from the northern North Island, making the palm somewhat resemble a feather duster.
Hedyscepe contains a single species, H. canterburyana the Big Mountain palm, which grows on mountain cliffs overlooking the sea on Lord Howe Island, Australia. However some studies throw doubt on the inclusion of Hedyscepe as a member of the Rhopalostylidinae. In some molecular phylogenetic analyses, Hedyscepe is nested in the New Caledonia endemic Basselinia.