Acorus shannai (Acoraceae), a new species from Southern China

By

Cheng, Zhuo
Liu, Xinyu
Yu, Nianting
Chen, Weizhe
Zhao, Haofeng
Li, Feifei
Long, Chunlin

Type

Article

Date of Publication

2025

Original Publication

PhytoKeys

Volume

251

Pages

175--188

Subjects

Acorus gramineus&gt , Acorus macrospadiceus , Guizhou Province , new taxon , taxonomy , var. macrospadiceus

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers [2010]-

Identifiers

DOI: https://doi.org/10.3897/phytokeys.251.139141

 

Abstract

Acorus shannai (Acoraceae) is a commonly used seasoning in southern China. It was previously misidentified as A. macrospadiceus (Yamam.) F. N. Wei & Y. K. Li before. Through comparison of morphological characteristics, distribution locations, and type specimen, we determined that the elevation of A. gramineus var. macrospadiceus Yamam to species status was incorrect. Therefore, we propose a formal description of a new species following nomenclature regulations. Based on morphological and plastid genomic data, this study formally describes and illustrates Acorus shannai, distributed in the Qiandongnan area of Guizhou Province and its surroundings, confirming it as a new species within the genus Acorus. This species is morphologically and phylogenetically distinct from other members of the A. gramineus group. Key distinguishing features include a strong fennel odor (vs. aromatic in “A. tatarinowii” and A. gramineus), fruit with prominent dorsal sutures (vs. inconspicuous dorsal sutures in “A. tatarinowii” and A. gramineus), and a leaf-shaped spathe that is about 2–3 times as long as the spadix (vs. more than 3 times in “A. tatarinowii”). Phylogenetic analysis showed that A. shannai is closely related to the other species in the A. gramineus group. The recognition of A. shannai is not only important for the species diversity and phylogenetic relationship of Acorus, but also can avoid the drug safety caused by using other Acorus species as A. shannai to eat and promote the conservation of A. shannai resources.