华北粉背蕨 hua bei fen bei jue

Cheilanthes kuhnii Milde, Bot. Zeitung (Berlin) 25: 149. 1867; Aleuritopteris caesia (Christ) Ching; A. caesia var. efarinosa H. S. Kung, Li Bing Zhang & X. S. Guo; A. kuhnii var. brandtii (Franchet & Savatier) Tagawa; A. kuhnii f. efarinosa (Makino) Tagawa; A. tenella (Ching & S. K. Wu) Saiki; C. brandtii Franchet & Savatier; C. brandtii var. efarinosa Makino; C. caesia Christ; C. farinosa (Forsskål) Kaulfuss var. brandtii (Franchet & Savatier) C. Christensen; C. kuhnii var. brandtii (Franchet & Savatier) Tagawa; C. kuhnii var. caesia (Christ) C. Christensen; C. kuhnii f. gracilis Kitagawa; C. lanceolata C. Christensen; Leptolepidium caesium (Christ) K. H. Shing & S. K. Wu; L. kuhnii (Milde) K. H. Shing & S. K. Wu; L. kuhnii var. brandtii (Franchet & Savatier) K. H. Shing & S. K. Wu; L. tenellum Ching & S. K. Wu.

Rhizomes erect, short; scales bicolorous, black with reddish brown margins, broadly lanceolate. Fronds clustered. Stipe reddish brown, lustrous, 10-20 cm, scaly at base or to midpoint of stipe; scales bicolorous, brown with lighter margins, translucent, narrowly ovate to ovate-lanceolate. Lamina oblong-lanceolate, 15-30 × 5-13 cm, pinnate-bipinnatifid, herbaceous when dry, abaxially with white farina or rarely non-farinose and usually glabrous, adaxially glabrous; pinnae 8-12 pairs, sessile or subsessile, distinct along rachis, basal pair of pinnae slightly shorter than or equal to second pair, ovate-triangular to oblong-lanceolate, 2.5-4(-7) cm, bipinnatifid; pinnules 4-6 pairs, basal basiscopic pinnules longer than adjacent acroscopic ones, 1-1.5 cm × 5-7 mm, ovate-oblong, pinnatifid; second and upper pairs gradually shortened distally. Veins pinnate, obscure or more conspicuous on adaxial surface. Sori consisting of several sporangia, confluent at maturity. False indusia continuous, herbaceous, margins undulate.

Rock crevices on dry slopes, forests; 1000-3500 m. Gansu, Hebei, Henan, Jilin, Liaoning, Nei Mongol, Shaanxi, Shanxi, Sichuan, Xizang, Yunnan [Japan, Korea, Russia].

Aleuritopteris kuhnii is widely distributed and exhibits great variation in lamina form. Aleuritopteris caesia was based on large-fronded plants of A. kuhnii.