Impatiens ngariensis (Balsaminaceae), a new species from Xizang, China

A new species, Impatiens ngariensis (Balsaminaceae) from western Xizang, China, is described in this study. Morphological and phylogenetic evidence supports its taxonomic placement within I. sect. Racemosae. Phylogenetic analyses indicate that I. ngariensis forms a clade with I. thomsonii, I. bomiensis, I. fragicolor, I. edgeworthii and I. glandulifera. Morphologically, the new species closely resembles I. sulcata in petiole with 2 basal glands, subcorymbose-racemose inflorescences, lateral sepals ovate, dorsal petal suborbicular and capsule linear, but can be distinguished by several key characteristics, including a suborbicular dorsal petal with a cordate base and a shorter spur.