taxonID	type	description	language	source
C2A34EBEE7005F18812E08D6F9B48F4F.taxon	description	Figs 2, 3 “ 山柰菖蒲 ” (Shan Nai Chang Pu)	en	Cheng, Zhuo, Liu, Xinyu, Yu, Nianting, Chen, Weizhe, Zhao, Haofeng, Li, Feifei, Long, Chunlin (2025): Acorus shannai (Acoraceae), a new species from Southern China. PhytoKeys 251: 175-188, DOI: 10.3897/phytokeys.251.139141
C2A34EBEE7005F18812E08D6F9B48F4F.taxon	diagnosis	Diagnosis. The strong fennel aroma of the plant, distinct dorsal sutures on the fruit, and a spathe length 2 – 3 times that of the spadix are diagnostic features that differentiate A. shannai from other species in the A. gramineus group. The new species belongs to the A. gramineus group based on the following characteristics: Leaves without conspicuous marginal swellings of the lamina and a distinct midrib (Li 1979). According to the key to the species of Acorus occurring in China (Li 1979; Li et al. 2010), the morphology of A. shannai is similar to “ A. tatarinowii ” and A. gramineus. However, A. shannai can be clearly distinguished by the following features: the whole plant emits a strong fennel odor (vs. aromatic in “ A. tatarinowii ” and A. gramineus), the fruit has distinct dorsal sutures (vs. inconspicuous dorsal sutures in “ A. tatarinowii ” and A. gramineus), and the leaf-shaped spathe is approximately 2 – 3 times longer than the spadix (vs. more than 3 times in “ A. tatarinowii ”).	en	Cheng, Zhuo, Liu, Xinyu, Yu, Nianting, Chen, Weizhe, Zhao, Haofeng, Li, Feifei, Long, Chunlin (2025): Acorus shannai (Acoraceae), a new species from Southern China. PhytoKeys 251: 175-188, DOI: 10.3897/phytokeys.251.139141
C2A34EBEE7005F18812E08D6F9B48F4F.taxon	description	Description. Herbs, perennials, helophyte plants. Plants 40 – 80 cm, without indumentum. Rhizome recumbent and stout, 10 – 20 × 0.5 – 0.8 (- 1.2) cm, strong Foeniculum vulgare – like aroma with fleshy fibrous roots, internodes, 0.6 – 0.7 cm. Leaf sheath, 0.7 – 1.5 cm, purple. Leaves several, about ten, light green, ensiform, 30 – 60 × 0.7 – 1.5 cm, midrib lacking, apex acuminate. The leaf base is folded in half, the middle is flat above, without distinct midrib, parallel veins up to 15 cm, and exceedingly slender but raised. Peduncles compressed triangular, 8 – 25 cm. Spadix is green and leaf-like, 10 – 41 cm., 2 – 3 times longer than Spadix. Spadix is straight or slightly curved, narrowly cylindrical to subcylindric, 5 – 13 × 0.5 – 0.7 cm, densely flowered, 3 – 4 flowers in one cross-section. Flowers are white, 1.5 – 1.7 mm. Infructescence, up to 1 cm thick, fruit sub oblong, yellow-green, 4 – 4.5 × 2 – 3 mm. Seeds oblong-ellipsoid to ovoid, 2.5 – 3 × 1 – 1.2 mm. Flower, May-June. Fruit, July-August. 2 n = 24.	en	Cheng, Zhuo, Liu, Xinyu, Yu, Nianting, Chen, Weizhe, Zhao, Haofeng, Li, Feifei, Long, Chunlin (2025): Acorus shannai (Acoraceae), a new species from Southern China. PhytoKeys 251: 175-188, DOI: 10.3897/phytokeys.251.139141
C2A34EBEE7005F18812E08D6F9B48F4F.taxon	etymology	Etymology. The specific epithet is derived from the local name “ shannai ”.	en	Cheng, Zhuo, Liu, Xinyu, Yu, Nianting, Chen, Weizhe, Zhao, Haofeng, Li, Feifei, Long, Chunlin (2025): Acorus shannai (Acoraceae), a new species from Southern China. PhytoKeys 251: 175-188, DOI: 10.3897/phytokeys.251.139141
C2A34EBEE7005F18812E08D6F9B48F4F.taxon	distribution	Distribution, habitat, and phenology. The locality of this taxon is Leishan County, located in the Qiandongnan Miao and Dong Autonomous Prefecture of Guizhou Province. Specimen records indicate this species is also distributed in Guangxi, Hunan, and surrounding areas (Fig. 4). A. shannai exhibits a preference for moist mountain slopes and brook-adjacent habitats, distinguishing it ecologically from other Acorus species. It typically grows at an elevation of less than 1,500 m a. s. l. The species has been observed flowering in May to June and fruiting in July to August.	en	Cheng, Zhuo, Liu, Xinyu, Yu, Nianting, Chen, Weizhe, Zhao, Haofeng, Li, Feifei, Long, Chunlin (2025): Acorus shannai (Acoraceae), a new species from Southern China. PhytoKeys 251: 175-188, DOI: 10.3897/phytokeys.251.139141
