山东肿足蕨 shan dong zhong zu jue

Hypodematium cystopteroides Ching, Icon. Filic. Sin. 3: t. 123. 1935, not Kuhn (1889).

Plants 17-45 cm tall. Rhizomes creeping, slender, densely scaly together with swollen stipe base; scales reddish brown, lanceolate, 8-15 × 2-3 mm, margin entire or sometimes crenulate, apex acuminate. Fronds approximate; stipe stramineous, 10-25 cm × ca. 1.3 mm, thin, glabrous; lamina ovate-pentagonal, 7-10 × 6-18 cm, herbaceous, both surfaces with sparse, golden, rod-shaped, glandular hairs, glandular hairs much more dense along rachis, costae, and veins, lamina cordate and 4-pinnatifid at base, acuminate and pinnatifid at apex; pinnae ca. 8 pairs, oblique, lower 1 or 2 pairs opposite, 3-4 cm apart, upper pairs alternate; basal pair largest, ovate-triangular, up to 10 cm, up to 6 cm wide at base, base broadly cuneate, with a 7-15 mm stalk, 3-pinnatifid, apex acuminate; ultimate pinnules ca. 7 pairs, subopposite, anadromous, oblique, oblong-lanceolate; proximal basiscopic one largest, 1-1.5 cm × 4-6 mm, base cuneate and decurrent, pinnatifid, apex shortly acuminate; segments 4-6 pairs, oblong, entire or with 1 or 2 crenations at margins; second and upper pairs of pinnae gradually shorter, oblong-lanceolate, base rounded-cuneate, apex acuminate. Veins obvious on both surfaces, oblique, ending at margin. Sori orbicular, 1 per segment, at middle of veinlets; indusia persistent, grayish white, reniform, medium-sized or small, with sparse glandular hairs. Spores ellipsoid, bearing inflated folds, with granular ornaments.

● Limestone crevices in shaded places. Shandong.