Taxonomic novelties within a non-monophyletic lineage: a new Mexican species of Desmopsis (Annonaceae)

A new species of Annonaceae endemic to Mexico is described and illustrated. Desmopsis dubia sp. nov. is placed within the Desmopsis-Stenanona clade and is clearly different from all other species of Neotropical Miliuseae by the combination of lower surface of leaves pubescent; tertiary venation strongly percurrent; leafy bracts absent at the base of the pedicels; sepals connate at the base and persistent in fruit; petals fleshy and stiff, elliptic to ovate with food bodies at the base of the inner ones; and cylindrical monocarps with ligneous exocarp. We discuss its phylogenetic relationships and placement within the genus Desmopsis and a key to the Mexican species of Desmopsis and Stenanona with yellow or greenish petals is provided.