Primula maershanensis (Primulaceae), a new species in Primula sect. Auganthus from Sichuan, China

Primula maershanensis J.L.Gu & Z.K.Wu, a new species of Primulaceae from Sichuan, China, is described and illustrated. Morphological evidence supports the placement of P. maershanensis within Primula sect. Auganthus, a section characterized by leaves that are shallowly to deeply lobed and covered with hairs and by a distinctively broad calyx with a flattened base. The new species is distinguished from other species in this section by its short rhizome and nearly fleshy roots; subpurple petioles and scapes; leaf blade suborbicular, wider than long, margin palmately 5–9-lobed to the middle of the blade; and a bright yellow corolla associated with long-homostylous flowers. Information on the distribution, morphological comparisons with closely related species, and the conservation status of the new species is also provided, along with a key to the known species of Primula sect. Auganthus.