Vincetoxicum is a genus of the milk weed family (Apocynaceae) which comprises 378 genera and about 5,350 species. Species of Vincetoxicum are shrubs, erect perennial herbs or herbaceous twiners. There are approximately 70 species of Vincetoxicum occurring in China, most of them are distributed in tropical or subtropical regions. 

During an expedition to Mount Emei, researchers from the Xishuangbanna Tropical Botanical Garden (XTBG) and their collaborators collected an unknown species of Vincetoxicum in May 2020 from the evergreen broad–leaved forest in Emeishan City. After literature review as well as morphological examination, they found it different from any other species of Vincetoxicum in morphological characters and confirmed it as new to science.  

The researchers named the new species as Vincetoxicum emeiense and got it published in Phytotaxa. 

Vincetoxicum emeiense is a twining plant. It is similar to V. hui and V. koi. in twining herbaceous life form, leaf, pleiochasium and corolla shape, but there are numerous features that can be used to distinguish them. 

Vincetoxicum emeiense has glabrous stem and adaxially puberulent leaf shape, and with adaxially puberulent and orange to purple corolla. 

The new species is so far only recorded from the type locality, Mount Emei, Sichuan Province at an elevation of about 757 meters, where it grows in evergreen broad–leaved forest. 

Since the investigation has not been thorough enough to fully understand the species natural distribution, the researchers regarded the conservation status of the new species as Data Dedicient according to the International Union for Conservation of Nature Red List categories and criteria. 

Flowering branch of Vincetoxicum emeiense. (Image by SHEN Jianyong)

Corolla lobes of Vincetoxicum emeiense. (Image by SHEN Jianyong)

Flowering branch of Vincetoxicum emeiense. (Image by SHEN Jianyong)

Inflorescence of Vincetoxicum emeiense. (Image by SHEN Jianyong)