Rubus phantasmaticus (Rosaceae), an overlooked new species of R. subg. Malachobatus from southwestern China

Rubus subg. Malachobatus is morphologically well-circumscribed at the subgeneric level, but its infrasubgeneric relationships remain unclear, and many taxa have been subject to significant taxonomic disputes. Based on molecular phylogenetic analyses of nuclear ribosomal ITS and complete plastome datasets, combined with comprehensive morphological comparisons, a new species from southwestern China is described here as R. phantasmaticus Q. P. Wang, X. Y. Dai & Huan C. Wang. Both datasets consistently resolve R. phantasmaticus as nested within R. subg. Malachobatus and most closely related to R. hypopitys . Morphologically, R. phantasmaticus clearly differs from R. hypopitys in its growth habit, leaf shape, and inflorescence architecture. Additionally, the two species are geographically adjacent but exhibit non-overlapping distributions. Rubus phantasmaticus has long been overlooked and was recently treated as a variety of R. chrysobotrys , but both morphological comparisons and molecular phylogenetic evidence indicate that R. phantasmaticus represents a distinct taxon with no close phylogenetic affinity to R. chrysobotrys .