Researchers from the Wuhan Botanical Garden of the Chinese Academy of Sciences have discovered a new species of the Impatiens during a plant diversity survey in the Ngari Prefecture of Xizang Autonomous Region, China. The study, published in PhytoKeys, describes the species as Impatiens ngariensis S. Peng, G. W. Hu & Q. F. Wang.

The newly discovered species was found in 2023 during field investigations in Zanda County, Ngari Prefecture, where it was initially noted for its resemblance to Impatiens sulcata. Through detailed morphological comparisons and molecular phylogenetic analyses based on nuclear nrITS and plastid atpB-rbcL sequence data, the researchers confirmed that the plant represents a new species belonging to the Impatiens section Racemosae. Phylogenetic analyses indicate that it forms a well-supported monophyletic lineage with species such as I. thomsonii.

The genus Impatiens comprises more than 1,000 species worldwide and mainly distributed in the tropical and subtropical regions of the Old World, including tropical Africa, Madagascar, southern India-Sri Lanka, the Eastern Himalayas, and Southeast Asia. In China, approximately 360 species of Impatiens have been recorded, most of which occur in southwestern China, including Yunnan, Sichuan, Xizang, and Guizhou. As of 2025, more than 70 species have been documented in Xizang, all belonging to Impatiens subgenus, with the majority assigned to section Racemosae. In 2024 alone, about eight new species of this genus were described worldwide, indicating that many potential new taxa remain to be discovered within this diverse lineage.

Impatiens ngariensis is an annual herb reaching 30-66 cm in height, bearing white to pale pink flowers. It inhabits in streamside wetlands under forest at an elevation of approximately 3,090 meters. Currently, the species is only known from a single population discovered in Zanda County, Ngari Prefecture. However, its potential distribution range and population size remain insufficiently investigated, the species has been preliminarily assessed as Data Deficient (DD) according to the IUCN Red List Categories and Criteria.

The discovery of this new species not only enriches the species diversity of Impatiens in Xizang, but also provides new material for studying the evolutionary history, adaptive radiation, and biogeographic patterns of the genus on the Qinghai-Tibetan Plateau.

This study was supported by the Science and Technology Major Project of Xizang and the Second Tibetan Plateau Scientific Expedition and Research programme.

Impatiens ngariensis (Image by LI Ruping)

Impatiens ngariensis (A1-H1), I. thomsonii (A2-H2) and I. sulcata (A3-H3) (Image by LI Ruping)