Research Paper

Lasianthus sondangii (Rubiaceae, Lasianthus section Nudiflorae), a new species with a unique spiciform inflorescence from Central Vietnam

Thi Thuy Nhan Tran, Van Canh Nguyen, Van Dung Luong, Thanh Nha Phan-Thi, Hoa Thi Nguyen, Ba Vuong Truong, Quoc Bao Nguyen

Published on: 26 May 2026

Page: 488 - 494

DOI: 10.6165/tai.2026.71.488

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    Abstract

    Lasianthus sondangii, a new species from Lasianthus section Nudiflorae, is described from Khanh Hoa Province, Central Vietnam. It can be distinguished from other Lasianthus species in Vietnam and surrounding countries by having narrowly triangular stipules, spiciform inflorescences with two or three reduced cyme secondary axes, purple flowers, and clavate calyx lobes with revolute margins. A detailed description of the new species, color plates, distribution, habitat and preliminary conservation assessment are provided.

    Keyword: Indochina, Khanh Hoa, Lasiantheae, plant conservation, plant diversity, sect. Nudiflorae

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