疏裂凤尾蕨 shu lie feng wei jue

Pteris finotii var. obtusa Tagawa.

Plants to 2.5 m tall. Rhizome erect, short and thick, ca. 2 cm in diam., apex with bright brown scales. Fronds clustered; stipe dark straw-colored to dark brown, ca. 100 cm, 7-12 mm in diam., glabrous; rachis straw-colored, glabrous; lamina with 3 pinnatisect divisions, ovate-triangular in outline, to more than 100 × 60 cm, central division ovate, columnar, to more than 80 × 35-40 cm, stalk 6-10 cm; two lateral branches smaller; lateral pinnules 6-8 pairs, opposite or subalternate, oblique, stalked (ca. 1 cm), upper ones sessile, broadly lanceolate, 20-27 × 6-10 cm, base rounded-truncate, apex caudate (4-8 cm); segments 13-20 pairs, alternate or basal pairs subopposite, linear-lanceolate, 25-70 × 4-7 mm, basally slightly enlarged, sterile margins slightly serrate, apex obtuse or acuminate; sterile pinnules with wider segments; terminal pinnule triangular, 20-25 × 15-18 cm, stalked (1.5-2 cm), base rounded-cuneate, along costule narrowly cuneate, pectinately divided with broadly winged costa, margins flat, obtusely serrate, apex linear-lanceolate (4-5 cm); costules prominent abaxially, straw-colored, glabrous, grooved adaxially, with inconspicuous spines or without spines; veinlets slender, conspicuous only abaxially, anastomosing to form a series of narrow areoles along costules and midvein, areoles along costules long and narrow, areoles along midvein irregularly polygonal, veins of segments free; lamina gray-green, herbaceous when dried, glabrous.

Forests, by small streams; 100-500 m. Guangdong, Hainan, S Yunnan (Hekou, Xishuangbanna) [N Vietnam].