Dryopteris polita Rosenst.

Family

Dryopteridaceae

Nomenclature

Dryopteris polita Rosenst., Repert. Spec. Nov. Regni Veg. 13: 218. 1914; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 317. 1941; Holttum, Rev. Fl. Malaya ed. 1, 2: 492. 1955 [‘1954’]; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 96. 1967; Tagawa & K.Iwats., Fl. Thailand 3: 353, f. 32.9 & 32.11. 1988; Boonkerd & Pollawatn, Pterid. Thailand: 204. 2000. – Dryopteris chapensis auct. non C.Chr. & Ching: Holttum, Dansk Bot. Ark. 20: 30. 1961, p.p.

Description

Rhizome short, ascending or suberect, scales light brown, entire, up to 18 by 2 mm. Stipes stramineous, scaly at base with the scales similar to those on rhizome, more sparsely scaly upwards with smaller ones up to 50 cm long. Laminae oblong with acuminate apex, bipinnate, up to 35 by 28 cm; 5 or 6 lower lateral pinnae nearly equal in size or slightly smaller upwards, with stalks of 1–2.5 cm long, narrowly subtriangular with acuminate apex, unequally broadly cuneate at base, 10–12 by 5.5 cm, sometimes with a slightly enlarged basal basiscopic pinnule on one or more pinnae; upper pinnae rather suddenly shortened, very shortly stalked, sessile or adnate at base, oblong-subdeltoid with acute apex, shallowly lobed at margin; pinnules oblong-subdeltoid, rounded at apex, round or cuneate at base or acroscopically auricled in larger ones, up to 3 by 1.2 cm, serrate at margin; papyraceous, not very thick or harsh, deep green. Sori dorsal on veinlets, medial or just beyond midway from midrib to margin of pinnule, in one row, indusia minute, round reniform, glabrous, lost before sori mature (commonly and erroneously described as exindusiate ).

Distribution in Thailand

NORTHERN: Chiang Mai, Tak; NORTH-EASTERN: Loei; CENTRAL: Nakhon Nayok; SOUTH-EASTERN: Chanthaburi; PENINSULAR: Ranong, Nakhon Si Thammarat.

Distribution in Cambodia

"Pnom Chon"

Wider Distribution

Indochina, W Malaysia, Sumatra, Borneo, Taiwan, and northwards to southern edge of Japan.

Ecology

On mountain slopes in not very dense mountain forests at 100–1500 m alt.

Proposed IUCN Conservation Assessment

Least Concern (LC). This species is widespread and not under any known threat.

Voucher specimens - Thailand

Middleton et al. 5087, Phitsanulok, Phu Hin Rong Kla National Park (E); Suksathan 4434, Chanthaburi, Khao Soi Dao (E, QBG).

Habit

Habit

Frond

Frond

Transverse section through rhizome

Transverse section through rhizome

Stipe

Stipe

Pinna from beneath

Pinna from beneath

Junction of pinnae with rachis

Junction of pinnae with rachis

Venation

Venation

Lower surface of frond with young sori

Lower surface of frond with young sori

Young sori (with tiny indusia barely visible)

Young sori (with tiny indusia barely visible)

Older sori

Older sori

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