Polystichum deltatum Li Bing Zhang, M.Q. Han & Yan Liu
Ha Giang Prov., Quan Ba Distr., Can Ty Commune, Sin Suoi Ho Village, around point 23.09566ºN 105.02142ºE. Very steep mountain slopes composed of solid highly eroded karstic limestone at elevation 800–1000 m a.s.l. Remnants of primary evergreen broad-leaved and coniferous (with Calocedrus rupestris and Xanthocyparis vietnamensis) humid forest. Lithophytic fern on steep rocky slope. Very common. 11 October 2019, L. Averyanov, Nguyen Sinh Khang, T. Maisak, VR 1583.
Coordinates (geographic position):23° 5′ 44.38″ N, 105° 1′ 17.11″ E ±1000 mRecord creation: 2019-12-31, Leonid Averyanov, PhotoScan D1Citation: Specimen LE 01067069 // Virtual herbarium of Komarov Botanical Institute RAS — http://re.herbariumle.ru/01067069