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| Aristolochia zhuhaiensis Y.Fan Wang & Z.R.Guo, in Wang, Guo, Landrein, Onyenedum et Liao. 2025. |
Abstract
A self-supporting new species of Aristolochiaceae, Aristolochia zhuhaiensis Y.Fan Wang & Z.R.Guo, is described and illustrated from Zhuhai City, Guangdong Province, China. Morphologically, this species exhibits vegetative characters, including leaf blade shape and growth form, that are similar to Aristolochia thwaitesii Hook., the only other known taxon in Aristolochia subg. Siphisia in Asia that is non-twining and self-supporting, native to southern Guangdong, particularly the Hong Kong Special Administrative Region. However, A. zhuhaiensis can be readily distinguished from A. thwaitesii by its unique floral morphology. The new species features a campanulate to funnel-shaped calyx limb densely covered with porcelain-white granular pustules. In contrast, A. thwaitesii has an elongated, concave tubular calyx limb with an adaxial surface that transitions from purple to pale yellow or white towards the apex, densely covered with recurved fleshy prickles. Aristolochia zhuhaiensis is endemic to Zhuhai City and has not been observed elsewhere. Detailed illustrations, photographic plates, a distribution map, a digitized holotype voucher specimen, a comparative table, and an identification key are provided to facilitate the differentiation of A. zhuhaiensis from A. thwaitesii.
Key words: Aristolochia subg. Siphisia, conservation status, fieldwork, morphology, taxonomy
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| Line drawing of Aristolochia zhuhaiensis by Ms. Yushan Cai A habit, showing a subshrubby growth form with basal inflorescences B roots fusiform or globose C, D front and lateral view of the flower E bud F bud sprouts in early development G, H gynostemium I adaxial side of the leaf J abaxial view of the leaf, pinnate venation. |
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| Illustration of Aristolochia zhuhaiensis A habit in situ B inflorescence in early development C inflorescence D lateral view of the flower E longitudinal section of the flower F front view of the bud G, H front view of the flower, showing the adaxial side of the calyx limb covered with porcelain-white granular pustules I–J gynostemium, from female stage (I) to male stage (J) K leaves (adaxial), L. Leaves (abaxial). Images B–E, I were provided by Mr. Yiwen Jiang. |
Aristolochia zhuhaiensis Y.Fan Wang & Z.R. Guo, sp. nov.
Diagnosis. Aristolochia zhuhaiensis shares morphological similarities with A. thwaitesii, both of which are distributed in neighboring regions and represent the only two known self-supporting, non-twining Aristolochia subg. Siphisia species in Asia. In terms of vegetative characteristics, these two congeners are highly similar; however, they can be readily distinguished by their markedly different floral morphologies. Aristolochia zhuhaiensis is characterized by a campaniform-infundibuliform calyx limb densely covered with porcelain-white granular pustules. It also features a conspicuous platform-shaped area beneath the perianth throat, which is white, glabrous, waxy, and slightly elevated upward. In contrast, A. thwaitesii possesses an elongated, concave tubular calyx limb with an adaxial surface that transitions from purple to pale yellow or white towards the apex. This species is entirely covered with recurved fleshy prickles and lacks the distinctive platform structure found in the calyx of A. zhuhaiensis. Detailed morphological comparisons between the new species and A. thwaitesii are shown in Figs 4, 5 and Table 1.
Yi-Fan Wang, Zi-Rui Guo, Sven Landrein, Joyce G. Onyenedum, Shuai Liao. 2025. Aristolochia zhuhaiensis, A self-supporting New Species of Aristolochiaceae from Guangdong, China and Notes on Aristolochia thwaitesii. PhytoKeys. 254: 61-76. DOI: doi.org/10.3897/phytokeys.254.139616
