Description from
Flora of China
Alsophila subglandulosa Hance, Ann. Sci. Nat., Bot., sér. 5, 5: 253. 1866; Aspidium intermedium Willdenow var. rhodolepis (C. B. Clarke) Christ; A. subtripinnatum Miquel; Ctenitis anyuanensis Ching & Chu H. Wang; C. calcarea Ching & Chu H. Wang; C. chungyiensis Ching & Chu H. Wang; C. costulisora Ching; C. dumrongii Tagawa & K. Iwatsuki; C. maolanensis P. S. Wang; C. membranifolia Ching & Chu H. Wang; C. rhodolepis (C. B. Clarke) Ching; C. subtripinnata (Miquel) H. Itô; C. yunnanensis Ching & Chu H. Wang; Cyathea subglandulosa (Hance) Copeland; Dryopteris maximowicziana (Miquel) C. Christensen var. rhodolepis (C. B. Clarke) Koidzumi; D. oldhamii (Baker) C. Christensen; D. rhodolepis (C. B. Clarke) C. Christensen; D. subglandulosa (Hance) Hayata (1917), not Kuntze (1891); D. subtripinnata (Miquel) Kuntze; Lastrea intermedia (Willdenow) C. Presl var. rhodolepis (C. B. Clarke) Beddome; Nephrodium rhodolepis C. B. Clarke; Polypodium oldhamii Baker.
Rhizomes erect, suberect, or prostrate; rhizome scales reddish brown, linear, 1.5-3 mm. Stipe dark stramineous, 40-50 cm; stipe scales appressed, reddish brown, lanceolate or ovate-lanceolate, 2-3 mm; scales on rachis and costae similar but smaller. Lamina 3-pinnate to 4-pinnatifid, ovate-triangular, 40-60 × 30-40 cm; pinnae 12-14 pairs; basal pinnae largest, triangular, 18-22 × 12-16 cm; pinnules 10-12 pairs; basal basiscopic pinnules of basal pinnae longest, 8-10 × 2.5-3.5 cm; bases of upper pinnae or lobes not obviously decurrent, without veinlets arising from rachis. Lamina herbaceous; veins free, distinct, no veinlets arising from costae. Sori medial or submedial, often near costae, indusiate; indusia usually fugacious, glabrous. Perispore coarsely echinate.
Ctenitis subglandulosa is a widespread and morphologically variable species. The indusia of this species are thin and colorless at an early stage but stop growing midway through its development. Therefore, in most herbarium specimens, the indusia are difficult to observe. However, sometimes the indusia are distinct and persistent. The size and abundance of the scales on stipes and rachises, the color and abundance of glands on the lamina beneath, as well as the abundance of hairs on the lamina are all variable characters. It is observed that when plants grow in open and dry habitats they develop hairs on the lower leaf surface, which are absent when growing in shade. Spore ornamentation of many samples of this species was examined, and we found most having echinate perispores, except one specimen from Hainan and one from Yunnan having folded perispores. The occurrence of these two different spore types may indicate that this is a species complex that needs more detailed taxonomic revision, preferably using molecular techniques.
Usually on limestone; sea level to 1700 m. Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hubei, Hunan, Jiangxi, Sichuan, Taiwan, Yunnan, Zhejiang [Bhutan, India, Malaysia, Philippines, Vietnam; SE Asia].