卵果双盖蕨 luan guo shuang gai jue

Basionym: Allantodia ovata W. M. Chu ex Ching & Z. Y. Liu, Bull. Bot. Res., Harbin 4(3): 12. 1984, not Diplazium cavalerianum (Christ) M. Kato, Bot. Mag. (Tokyo) 90: 31. 1977 [Allantodia cavaleriana Christ, Bull. Acad. Int. Géogr. Bot. 16: 243. 1906]; Allantodia cavaleriana (Christ) Ching (1964); Athyrium cavalerianum Christ.

Plants medium-sized. Rhizome creeping, ca. 1 cm in diam., apex densely scaly; scales brown, lanceolate, ca. 1 cm, membranous, margin entire; fronds distant to caespitose. Fertile fronds up to 1.1 m; stipe dark brown at base, upward light brown to dark stramineous, up to 50 cm, up to 5 mm in diam., base densely scaly, upward glabrous; lamina 2-pinnate with pinnatipartite pinnules, deltoid, ca. 40 cm, apex acuminate; pinnae 10-15 pairs, mostly opposite or subopposite, shortly stalked, slightly ascending, lower pinnae broadly oblong-lanceolate or slightly asymmetrical (basiscopic pinnules longer), up to 25 × 13 cm, upper pinnae lanceolate, 3-10 cm × 7-30 mm; pinnules ca. 15 pairs, mostly alternate, spreading, contiguous, sessile or subsessile, lanceolate, up to 7 × 1.8 cm, base broadly cuneate or slightly shallowly cordate, apex acuminate; basal 1 or 2 pairs of pinnules short, sometimes quite short, 1-pinnatipartite to 2/3-3/4 to costule; pinnule lobes up to ca. 15 pairs, contiguous, ascending, oblong or rectangular, slightly oblique, margin sparsely serrate or subentire, apex rounded to truncate; veins pinnate, prominent abaxially, veinlets up to 7 pairs per lobe, simple or forked, ascending. Lamina thinly herbaceous when dry, green, glabrous; rachis and costa light brown to dark stramineous, glabrous, shallowly grooved adaxially. Sori elliptic-orbicular, slightly longer than wide, up to 6 pairs, costular; indusia gray, thinly membranous, vaulted when mature, irregularly ruptured at back. Spores bean-shaped, perispore not prominent, with ridge-shaped ornamentation.

Evergreen broad-leaved forests in valleys, beside streamlets; 800-2400 m. Chongqing, Guizhou, Sichuan, Yunnan [Vietnam].