Ctenitis dumrongii Tagawa & K.Iwats.

Family

Dryopteridaceae

Nomenclature

Ctenitis dumrongii Tagawa & K.Iwats., Acta Phytotax. Geobot. 23: 115, f. 11. 1968; Tagawa & K.Iwats., Fl. Thailand 3: 357, f. 33, 1–3. 1988; Boonkerd & Pollawatn, Pterid. Thailand: 200. 2000.

Description

Rhizome short, erect. Stipes densely scaly at base, about 40 cm long, dark brown; scales at base of stipe linear, up to 25 by 1 mm, brown or paler on basal part, entire, thin, those on the upper part linear-lanceolate, up to 10 by 0.6 mm, dark brown, clathrate, gradually becoming smaller upwards. Laminae narrowly oblong-subtriangular, gradually narrowing towards acuminate apex, about 60 by 35 cm, quadripinnatifid in basal part; pinnae about a dozen pairs below an indistinct apical pinna, the lower pinnae 8–12 cm apart; basal pinnae the largest, stalked, asymmetrically oblong-subdeltoid, acuminate at apex, cuneate at base, up to 20 by 12 cm; posterior pinnules of the basal pinna like the upper pinnae; pinnules of middle pinna sessile, oblong, rounded or moderately acute at apex, 2.5–5 by 0.8–1.5 cm; papyraceous or thicker, green, midrib of pinnules scaly beneath, densely hairy above with articulated hairs, main veins hairy above, veinlets 3–6 pairs, simple or forked. Sori costular to medial, indusiate; indusia fringed in matured sori but persistent, thin, glabrous .

Distribution in Thailand

NORTHERN: Chiang Mai, Chiang Rai.

Wider Distribution

Endemic to Thailand.

Ecology

On moist banks of streamlets in dense evergreen forests at medium altitudes.

Proposed IUCN Conservation Assessment

Data Deficient (DD). This species has a relatively narrow distribution but the exact distribution and current threats to its population are unknown.

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