雪白粉背蕨 xue bai fen bei jue

Cheilanthes niphobola C. Christensen, Acta Horti Gothob. 1: 88. 1924; Aleuritopteris niphobola var. concolor Ching; A. niphobola var. pekingensis Ching & Y. P. Hsu.

Rhizomes erect, short; scales concolorous or often bicolorous, uniformly reddish brown or with dark central stripe and lighter margins, lanceolate. Fronds clustered. Stipe reddish brown or ebony, 4-13 cm, glabrous or occasionally with sparse scales as those of rhizome. Lamina dark green, pentagonal, nearly as long as broad, 1.5-4 cm, tripinnatifid, papery or herbaceous when dry, abaxially with snow-white farina, adaxially glabrous; rachis and costae of same color as stipe. Pinnae 2 or 3 pairs, connected to rachis by narrow wings; basal pair largest, triangular, inequilateral, bipinnatifid; basal basiscopic pinnule largest, pinnatifid; ultimate segments narrowly oblong, margins entire; second pinnae oblong-lanceolate or lanceolate, pinnatifid or entire. Veins pinnate, obscure. Sori consisting of 1-3 sporangia, discrete. False indusia continuous, pale green, broad, margins entire.

● Rock crevices; 300-3400 m. Gansu, Hebei, Nei Mongol, Ningxia, Shaanxi, Shanxi, Sichuan, Xizang.

Aleuritopteris niphobola var. concolor was based on a specimen from Gansu apparently lacking abaxial frond farina. Examination of the type specimen at PE reveals that it possesses dense farinose glands abaxially but that the farina were lost during the drying process.