Abstract
Artabotrys pachypetalus sp. nov. is described from Guangdong, Guangxi, Guizhou, Hunan and Jiangxi in China. A detailed description, distribution data, along with a color plate and a line drawing are provided. In China, specimens representing this species were formerly misidentified as A. multiflorus or A. hongkongensis (= A. blumei). Artabotrys blumei typically has a single flower per inflorescence, whereas both Artabotrys pachypetalus and A. multiflorus have multiple flowers per inflorescence. In addition, A. pachypetalus is readily distinguished from A. multiflorus in having thicker and shorter petals, and connivent and somewhat trigonal or terete inner petal blades. Artabotrys pachypetalus is most similar to A. punctulatus because both have multi-flowered inflorescences and similar petal length, but A. pachypetalus differs in having cream petals in vivo, connivent inner petal blades, and a short, raised rim above the inner petal claw. Artabotrys multiflorus should be excluded from the flora of China because none of the Chinese specimens of Artabotrys collected so far fall within the variation of A. multiflorus.