雅砻粉背蕨 ya long fen bei jue

Rhizomes ascending, short; scales bicolorous, dark brown with lighter margins, linear-lanceolate. Fronds clustered. Stipe brown or reddish brown, lustrous, 18-25 cm. Lamina ovate-pentagonal, 15-24 × 12-18 cm, 3-pinnatifid, papery when dry, abaxially with white farina, adaxially glabrous; rachis and costae brown. Pinnae 5 or 6(-8) pairs, angled obliquely upward, decurrent at base, distal lobes linear to narrowly oblong, with broad U-shaped sinuses between lobes; basal pair largest, 8-12 × 4-9 cm, triangular, inequilateral, 2-pinnatifid, medial pinnae attenuate at tips; pinnules ca. 5 pairs, alternate, basal basiscopic pinnule largest, 5-7 × 1.5-2 cm, lanceolate, pinnatifid; second pinnae shorter than basal one and third one, 2-4 cm × 5-8 mm, other pairs gradually shortened distally, lanceolate, 1-pinnatifid or simple; ultimate segments distant from each other, lanceolate, narrow. Veins pinnate, obscure. Sori consisting of 3 to several sporangia, borne at vein tips. False indusia continuous, gray, membranous, margins entire.

● Rare; ca. 2000 m. SW Sichuan (Dechang).

Aleuritopteris yalungensis resembles A. tamburii but differs in its finely dissected fronds and lanceolate ultimate segments.