Research Paper

Aristolochia pendulistoma, a new species of Aristolochiaceae from Nujiang Canyon, Yunnan, China

Xinjie Zhao, Jidong Ya, Zirui Guo, Cheng Liu, Wei Zhang, Qi Peng, Hui Yang, Ting Zhang, Yifan Wang

Published on: 09 June 2026

Page: 531 - 537

DOI: 10.6165/tai.2026.71.531

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    Abstract

    Aristolochia pendulistoma is described and illustrated herein as a new species of Aristolochia subg. Siphisia from Nujiang Lisu Autonomous Prefecture, Yunnan, China. The species is readily recognized by its pendulous, bright orange, tridentate calyx limb, a striking floral configuration not documented in any other members of the subgenus. It is currently known from only two extant populations occurring on opposite slopes of the Nujiang River valley, indicating a high degree of regional endemism. Owing to its extremely restricted distribution and small population size, the species is preliminarily assessed as Critically Endangered under the IUCN Red List criteria and qualifies as a Plant Species with Extremely Small Populations (PSESP). Detailed morphological descriptions, comparative analyses with allied species, illustrations, and a distribution map are provided to clarify its taxonomic placement and to further document the diversity of Aristolochia in this region.

    Keyword: Aristolochia obliqua, Aristolochia sanheensis, Critically Endangered, extremely small populations, Salween, vine

    Literature Cited

    Buchwalder, K., Samain, M.-S., Sankowsky, G., Neinhuis, C., Wanke, S. 2014 Nomenclatural updates of Aristolochia subgenus Pararistolochia (Aristolochiaceae). Aust. Syst. Bot. 27(1): 48–55.
    DOI: 10.1071/SB13042View Article Google Scholar

    Do, T.V., Luu, T.H., Wanke, S., Christoph, N. 2015 Three new species and three new records of Aristolochia subgenus Siphisia from Vietnam including a key to the Asian species. Syst. Bot. 40(3): 671–691.
    DOI: 10.1600/036364415X689140View Article Google Scholar

    Gonz?lez, F. 1999 Inflorescence morphology and the systematics of Aristolochiaceae. Syst. Geogr. Pl. 68(1/2): 159–172.
    DOI: 10.2307/3668598View Article Google Scholar

    Gonz?lez, F., Stevenson, D.W. 2000a Gynostemium development in Aristolochia (Aristolochiaceae). Bot. Jahrb. Syst. 122: 249–291.
    DOI: 10.1007/s12228-022-09704-0View Article Google Scholar

    Gonz?lez, F., Stevenson, D.W. 2000b Perianth development and systematics of Aristolochia. Flora 195(4): 370–391.
    DOI: 10.1016/S0367-2530(17)30995-7View Article Google Scholar

    Gonz?lez, F., Wagner, S.T., Salomo, K., Symmank, L., Samain, M.-S., Isnard, S., Rowe, N.P., Neinhuis, C., Wanke, S. 2014 Present trans-Pacific disjunct distribution of Aristolochia subgenus Isotrema (Aristolochiaceae) was shaped by dispersal, vicariance and extinction. J. Biogeogr. 41(2): 380–391.
    DOI: 10.1111/jbi.12198View Article Google Scholar

    Guo, Z., Wang, Y., Onyenedum, J.G., Li, J. 2025 Aristolochia geantha (Aristolochiaceae), a new species from Yunnan, China. Taiwania 70(2): 293–300.
    DOI: 10.6165/tai.2025.70.293View Article Google Scholar

    Hwang, S.M. 1981 Materials for Chinese Aristolochia. Acta Phytotax. Sin. 19(2): 222–231.

    IUCN 2012 IUCN Red List Categories and Criteria: Version 3.1. Second edition. IUCN, Gland, Switzerland and Cambridge, [iv+] 32 pp.

    IUCN 2024 Guidelines for Using the IUCN Red List Categories and Criteria Version 2024-3. Standards and Petitions Committee of the IUCN Species Survival Commission. 122 pp.

    Lu, C.T., Yang, C.L., Hung, Y.L., Chen, P.H., Wang, J.C. 2022 A taxonomic revision on Isotrema (Aristolochiaceae) in Taiwan, including one new species. Taiwania 67(3): 391–407.
    DOI: 10.6165/tai.2022.67.391View Article Google Scholar

    Lu, Z., Qin, H., Jin, X., Zhang, Z., Yang, Q., Hong, D., Li, D., Li, K., Yuan, L., Zhou, Z. 2021 On the necessity, principle, and process of updating the list of national key protected wild plants. Biodivers. Sci. 29(12): 1577–1582.
    DOI: 10.17520/biods.2021394View Article Google Scholar

    Ma, Y., Chen, G., Edward Grumbine, R., Dao, Z., Sun, W., Guo, H. 2013 Conserving plant species with extremely small populations (PSESP) in China. Biodivers. Conserv. 22(3): 803–809.
    DOI: 10.1007/s10531-013-0434-3View Article Google Scholar

    Mo, M.-L., Wu, Y.-D., Huang, Y.-S., Lu, Z.-C. 2025 Isotrema jinquanii (Aristolochiaceae), a new species from limestone areas of Guangxi, China. Nord. J. Bot. 2025(6): e04667.
    DOI: 10.1002/njb.04667View Article Google Scholar

    Ohi-Toma, T., Sugawara, T., Murata, H., Wanke, S., Neinhuis, C., Murata, J. 2006 Molecular phylogeny of Aristolochia sensu lato (Aristolochiaceae) based on sequences of rbcL, matK, and phyA genes, with special reference to differentiation of chromosome numbers. Syst. Bot. 31(3): 481–492.
    DOI: 10.1600/036364406778388656View Article Google Scholar

    Ohi-Toma, T., Murata, J. 2016 Nomenclature of Isotrema, Siphisia, and Endodeca, and their related infrageneric taxa of Aristolochia (Aristolochiaceae). Taxon 65(1): 152–157.
    DOI: 10.12705/651.11View Article Google Scholar

    Shao, S.-C., Xie, X.-T., Liu, H.-M., Schneider, H., Li, B. 2025 Recommendations to Reinforce the Implementation of China’s Updated National Key Protected Wild Plants List. Integr. Conser. 4(4): 527–533.
    DOI: 10.1002/inc3.70061View Article Google Scholar

    Wagner, S.T., Hesse, L., Isnard, S., Samain, M.-S., Bolin, J., Maass, E., Neinhuis, C., Rowe, N.P., Wanke, S. 2014 Major trends in stem anatomy and growth forms in the perianth-bearing Piperales, with special focus on Aristolochia. Ann. Bot. 113(7): 1139–1154.
    DOI: 10.1093/aob/mcu044View Article Google Scholar

    Wang, Y., Liao, S., Landrein, S., Nguyen, K.S., Onyenedum, J.G., Guo, Z. 2026 Aristolochia ferox, a new species of subg. Siphisia (Aristolochiaceae) from Guangxi, China. PhytoKeys 273: 171–183.
    DOI: 10.3897/phytokeys.273.169468View Article Google Scholar

    Wang, Y.F., Guo, Z.R., Landrein, S., Onyenedum, J.G., Liao, S. 2025 Aristolochia zhuhaiensis, a self-supporting new species of Aristolochiaceae from Guangdong, China and notes on Aristolochia thwaitesii. PhytoKeys 254: 61–76.
    DOI: 10.3897/phytokeys.254.139616View Article Google Scholar

    Wanke, S., Gonz?lez, F., Neinhuis, C. 2006 Systematics of pipevines: combining morphological and fast?evolving molecular characters to investigate the relationships within subfamily Aristolochioideae (Aristolochiaceae). Int. J. Plant Sci. 167(6): 1215–1227.
    DOI: 10.1086/508024View Article Google Scholar

    Wanke, S., Granados Mendoza, C., M?ller, S., Paizanni Guill?n, A., Neinhuis, C., Lemmon, A.R., Lemmon, E.M., Samain, M.-S. 2017 Recalcitrant deep and shallow nodes in Aristolochia (Aristolochiaceae) illuminated using anchored hybrid enrichment. Mol. Phyl. Evol. 117: 111–123.
    DOI: 10.1016/j.ympev.2017.05.014View Article Google Scholar

    Yang, J., Cai, L., Liu, D., Chen, G., Gratzfeld, J., Sun, W. 2020 China’s conservation program on Plant Species with Extremely Small Populations (PSESP): Progress and perspectives. Biol. Conserv. 244: 108535.
    DOI: 10.1016/j.biocon.2020.108535View Article Google Scholar

    Yang, J.-M., Huang, R.Z., Liu, J.Z., Zhang, C.J., Yang, Y.R., Yin, L. 2024 Aristolochia sanheensis (Aristolochiaceae), a new species from Yunnan, Southwest China. Phytotaxa 666(3): 223–228.
    DOI: 10.11646/phytotaxa.666.3.6View Article Google Scholar

    Ying, S. 2025 New Taxa and New Names. 8. Research Center of Flora of Taiwan, Taipei. 572 pp.

    Zhang, H.L., Wang, Y.F., Guo, Z.R., Zhu, T., Yang, H.H., Yin, Z.J. 2024 Aristolochia pulvinata, a new species of Aristolochiaceae from Yunnan, Southwest China. Phytotaxa 675(3): 261–272.
    DOI: 10.11646/phytotaxa.675.3.5View Article Google Scholar

    Zhu, X.X., Li, X.Q., Liao, S., Du, C., Wang, Y., Wang, Z.H., Yan, J., Zuo, Y.J., Ma, J.S. 2019a Reinstatement of Isotrema, a new generic delimitation of Aristolochia subgen. Siphisia (Aristolochiaceae). Phytotaxa 401(1): 1–23.
    DOI: 10.11646/phytotaxa.401.1.1View Article Google Scholar

    Zhu, X.X., Zheng, H.L., Wang, J., Gao, Y.Q., Ma, J.S. 2019b Taxonomic studies on the genus Isotrema (Aristolochiaceae) from China: I. I. cangshanense, a new species from Yunnan. PhytoKeys 134: 115–124.
    DOI: 10.3897/phytokeys.134.37243View Article Google Scholar

    Zhu, X.X., Ma, J.S. 2022 Aristolochia and Isotrema of Aristolochiaceae in China. In: Ma, J.S. et al., (eds.), China, Mother of Gardens, in the Twenty-First Century, 1st ed. 2: 190–330. China Forestry Publishing House, Beijing, China.