Research Paper

Ryticaryum kaorahai (Icacinaceae s.str.), a new species from Halmahera, and the first new species in the genus for over one hundred years

Timothy M.A. Utteridge, Deby Arifiani, Wahyudi Santoso

Published on: 07 January 2026

Page: 49 - 54

DOI: 10.6165/tai.2026.71.49

Abstract

A new species of Ryticaryum, Ryticaryum kaorahai Utteridge & Arifiani, collected from Weda Bay, Halmahera, is described as new to science here. This species is unique in the relatively large oblong-elliptic leaves with unequal bases, and the large fruits to 4.5 cm long. It is the first arborescent member of the Icacinaceae s.str., to be described from Malesia in over a century.

Keyword: Icacinales, Indonesia, Malesia, Maluku, Moluccas, Ryticaryum macrocarpum, Ryticaryum purpurascens, Wallacea

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