Volume 3 > Part 4 > Year 1989 > Page 501 > Polypodiaceae > Pyrrosia

10. Pyrrosia tonkinensis (Giesenh.) Chingwfo-0001125752

Bull. Chin. Bot. Soc. 1: 55. 1935; Tardieu & C.Chr. Fl. Indo-Chine 7(2): 506. 1941; Tagawa & K.Iwats., S.E. Asian Stud. 5: 45. 1967.— Niphobolus tonkinensis Giesenh., Nipholobus: 144. 1901.— Pyrrosia porosa var. tonkinensis (Giesenh.) Hovenkamp, Blumea 30: 208 (1984); Leiden Bot. Ser. 9: 229. 1986. Fig. 50. 6.

Accepted Name : This is currently accepted.

Description : Rhizome creeping, about 2 mm diam., bearing fronds rather closely, densely scaly except in older portion; scales oblong-subulate, long-tailed at apex, up to 4 by 1 mm, dark brown to nearly black in central portion, brown in other part, thin, entire, without marginal hairs. Stipes not distinct with wings decurrent from laminae. Laminae linear, up to 30 cm long, commonly up to 7 mm but rarely up to 10 mm broad, gradually narrowing towards both apex and base; midrib grooved on upper surface, raised beneath, glabrescent; freshy, rather leatherly, veins invisible, upper surface steallate hairy or glabrescent, lower surface covered with two kinds of hairs, the lower grey appressed hairs and the upper pale stellate hairs with short stalks. Sori on the whole lower surface of upper half of fronds, covered with stellate hairs when young.

Thailand : NORTHERN: Chiang Rai (Doi Tung), Chiang Mai (Doi Chiang Dao), Lamphun (Doi Khun Tan); EASTERN: Chaiyaphum (Nam Phrom, Chulaporn Dam), Nakhon Ratchsima (Khao Lotueng); NORTH-EASTERN: Loei (Phu Luang);SOUTH-WESTERN: Kanchanaburi (Si Sawat).

Distribution : S China (Kweichow, Kwangsi, Hainan), Laos, N Vietnam (type).

Ecology : On mossy tree-trunks or on rocks usually in mountain forests a high altitudes (600–1,600 m), rather rare.

Notes: Pyrrosia tonkinensis is distinguished from P. mollis by linear fronds, typically less than 7 mm broad, covered densely with greyish tomentum and rather sparsely with short-stalked stellate hairs.

E-version notes : For more details see Ferns of Thailand, Laos and Cambodia.