Angiopteris weimingii (Marattiaceae): a new endangered fern species from southern Yunnan, China, revealed by morphology and phylogeny

Angiopteris weimingii, a morphologically distinct new species of Angiopteris (Marattiaceae) from southern Yunnan, China, is described. Compared with A. itoi, the new species can be distinguished by a taller habit (1.2–2.5 m vs. 0.5–1.5 m), a greater number of pinnae pairs (8–13 pairs vs. 4–9 pairs), a caudate tip (1 cm vs. 2–4 cm), the position of sori from the leaf margin (2 mm vs. 3–5 mm), spore color (yellow vs. white), and spore ornamentation (densely verrucate vs. clavate-echinate).

Molecular phylogenetic analyses confirm its affinity with the Archangiopteris clade. With a single known population of approximately 30 adults and severe habitat destruction, the species is assessed as Critically Endangered (CR) under IUCN criteria.