Sunday, April 14, 2024

[Botany • 2024] Cynanchum pingtaoi (Apocynaceae: Asclepiadoideae) • A New Species from Yunnan, China

 

Cynanchum pingtaoi S.Jin Zeng, G.D.Tang & Miao Liao, 

in Liao, S.-J. Zeng, L.-Y. Zeng, Yin, Yan, Zhang et Tang, 2024.
秉滔大花藤  ||  DOI: 10.3897/phytokeys.241.111499

Abstract
Cynanchum pingtaoi S.Jin Zeng, G.D.Tang & Miao Liao, sp. nov. (Apocynaceae) from Yunnan Province, China, is described and illustrated based on morphological and molecular evidence. Its deeply cordate to reniform leaves and campanulate, large flowers show that it is a member of former Raphistemma Wall., which has been included in Cynanchum L.. It is different from all former Raphistemma species by the broadly ovate corolla lobes, purple-red corolla and connivent corona tip slightly exceeding the corolla throat. Meanwhile, Cynanchum longhushanense G.D.Tang & Miao Liao, nom. nov. is proposed as replacement name for Raphistemma brevipedunculatum Y.Wan, which was considered a synonym of Cynanchum hooperianum (Blume) Liede & Khanum but is here reinstated as a distinct species because of significant morphological differences.

Key words: Cynanchum hooperianum, Cynanchum longhushanense, Cynanchum pingtaoi, morphology, phylogeny, Raphistemma, taxonomy

Cynanchum pingtaoi S.Jin Zeng, G.D.Tang & Miao Liao
 a habitat b inflorescence and leaf c inflorescence d flower buds e top view of flower f bracteoles at base of pedicel g side view of flower h corolla and corona separation, showing gynostegium, corona and corolla lobes (outer surface: upper right hand corner; inner surface: to the left of the outer surface) i pollinarium from dry specimen j young seeds k longitudinally opened half follicle showing seed arrangement l follicle, different views to show the three ribs m transverse section through follicle n follicle and leaves.
 All photos based on Si-Jin Zeng & Lin-Ya Zeng SJ4825 (IBSC).

 Cynanchum pingtaoi S.Jin Zeng, G.D.Tang & Miao Liao, sp. nov.
  
Diagnosis: Cynanchum pingtaoi resembles C. longhushanense, differing by its broadly ovate corolla lobes (vs. oblong), the purple-red inner surface of the corolla (vs. white), and the corona-scales apex connivent, slightly exceeding the corolla throat (vs. corona-scales apex connivent, not exceeding the throat of the corolla).

Etymology: The specific epithet pingtaoi honors the eminent botanist Ping-Tao Li (李秉滔), who is an expert in the Apocynaceae.
Chinese name: Bingtao Dahuateng (秉滔大花藤).


 Miao Liao, Si-Jin Zeng, Lin-Ya Zeng, Hai-Jun Yin, Mao-Lin Yan, Cai-Fei Zhang and Guang-Da Tang. 2024. A New Species and A replacement name in Cynanchum (Apocynaceae, Asclepiadeae) from China. PhytoKeys. 241: 49-63. DOI: 10.3897/phytokeys.241.111499