Ctenitis subobscura (Christ) Holttum

Family

Dryopteridaceae

Nomenclature

Ctenitis subobscura (Christ) Holttum, Fern Gaz. 12: 320. 1984; Tagawa & K.Iwats., Fl. Thailand 3: 620. 1988; Holttum, Fl. Males., Ser. II, Pterid. 2: 31. 1991; Boonkerd & Pollawatn, Pterid. Thailand: 201. 2000. – Phegopteris subobscura Christ, Bull. Herb. Boiss. 6: 836. 1898. – Type: G.Schneider 35, Sumatra (P).

Ctenitis mannii auct. non (C.Hope) Ching: Tagawa & K.Iwats., Fl. Thailand 3: 357. 1988.

Description

Rhizome short, erect; scales linear, thin, light brown, up to 20 by 1.5 mm, entire. Stipes 20–50 cm long, dark brown, densely scaly throughout; scales linear, up to 8 mm long, 2–3 cells broad near base, dark brown, like bristles. Laminae oblong-lanceolate, gradually narrowing from the broadest part at base towards acuminate apex, 35–45 by up to 20 cm, tripinnatifid at base; pinnae more than 15 pairs below bipinnatifid indistinct apical portion; basal pinnae the largest, asymmetrically oblong-subtriangular, acuminate at apex, truncate to broadly cuneate at base, stalked, about 12 by 6 cm; middle pinnae oblong-lanceolate, ascending, acuminate at apex, subtruncate or very broadly cuneate at base, pinnatifid or deeply lobed, very shortly stalked or subsessile, up to 10 by 3 cm; posterior pinnules larger, pinnatifid, up to 5 by 1.5 cm, other pinnules slightly oblique, moderately acute at apex, subentire or very slightly crenate at margin; herbaceous, deep green, rachis and costa densely scaly underneath, densely hairy above with Ctenitis-hairs; veins simple or forked. Sori medial; indusia so small that they appear absent.

Distribution in Thailand

SOUTH-WESTERN: Phetchaburi; PENINSULAR: Phangnga, Nakhon Si Thammarat, Satun, Yala.

Wider Distribution

NE India and Malesia.

Ecology

Terrestrial on mountain slopes in dense evergreen forests at medium altitudes.

Proposed IUCN Conservation Assessment

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

Voucher specimens - Thailand

Middleton et al. 5340, Satun, Thale Ban National Park (E).

Habit

Habit

Habit

Habit

Habit

Habit

Rhizome

Rhizome

Unfurling frond

Unfurling frond

Lamina

Lamina

Basal pinnae

Basal pinnae

Lower surface of lamina

Lower surface of lamina

Upper surface of lamina

Upper surface of lamina

Sori

Sori

Site hosted by the Royal Botanic Garden Edinburgh. Content managed by Stuart Lindsay, Gardens by the Bay, Singapore and David Middleton, Singapore Botanic Gardens. Last updated 16 November 2016.