Traditionally, the genus Aristolochia L. sensu lato is the largest genus of the family Aristolochiaceae. According to recent morphological and phylogenetic studies, Aristolochia subgen. Siphisia was reinstated as an independent genus Isotrema.
During botanical exploration, researchers from Xishuangbanna Tropical Botanical Garden (XTBG) collected an unknown species of Isotrema in the Menglai Grand Canyon, Cangyuan County, Yunnan Province. After careful morphological examination and literature review, they confirmed that it represented a new species.
The new species was named as Isotrema cangyuanense to refer its type locality, Cangyuan County and published in Taiwania on August 24.
Isotrema cangyuanense is a perennial, woody liana. It is morphologically similar to Isotrema kunmingense and I. moupinense, but easily distinguished by its densely villous leaf blade. The adaxial leaf surface is densely villous, the inside of calyx tube has dark reddish-brown papillae in upper portion, the calyx throat and adaxial surface of calyx limb are brownish, with densely dark reddish brown papillae.
The new species is also similar to I. moupinense, but easily distinguished by its both surface of densely villous leaf blade; shorter utricle; the inner surface of tube brownish, with densely dark reddish-brown papillae in the upper portion; throat brownish, with densely dark reddish-brown papillae,etc.
Isotrema cangyuanense is currently known only from Sigangli Village, Menglai Township, Cangyuan County, Yunnan Province, China, grows in limestone forest at ca. 1200 m high elevation, on the southern slope, and the soil type is red soil. The researchers proposed the conservation status of the new species as ‘Data Deficient’ (DD), since the field surveys are still limited.
Contact
SHEN Jianyong
Department of Gardening and Horticulture, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China
E-mail: sehnjianyong@xtbg.ac.cn
Isotrema cangyuanense (Image by MA Xingda)
Isotrema cangyuanense (Image by MA Xingda)
Isotrema cangyuanense (Image by MA Xingda)
