Curcuma deliniana, a Rare New Curcuma Species (Zingiberaceae) Previously Misidentified as C. wenyujin.

A new triploid Curcuma species from Guangxi in China, C. deliniana, is described and illustrated. It was previously misidentified as the valuable medicinal plant C. wenyujin but can be readily distinguished from the latter by its rarely branched rhizomes, slender shoots, narrow leaf blades, and small inflorescences. The species is used as a substitute or adulterant of another medicinal species, C. kwangsiensis, from which it differs in larger, nearly globose main rhizomes; green leaf blades that are glabrous adaxially and sparsely puberulent or glabrous abaxially; inflorescence with fewer, loosely arranged bracts; more broadly elliptic coma bracts, non-reflexed at tips; nearly rounded, whitish green fertile bracts with purple tips; white corolla lobes; and chromosome number 2n = 63. Phylogenetic analyses based on the plastid genomes recovered it as sister to C. aff. plicata while analyses based on single-copy orthologous genes placed it as sister to C. kwangsiensis with very weak support. Due to its limited populations and potential risk of continuing decline in the number of mature individuals, it is provisionally assessed as Endangered (EN) according to the IUCN Red List Guidelines. This discovery not only provides important insights into the species identification and evolutionary relationships within the economically important genus Curcuma but also highlights the importance of ensuring the authenticity of herbal raw materials.