Cyclosorus dentatus (Forssk.) Ching

Family

Thelypteridaceae

Nomenclature

Cyclosorus dentatus (Forssk.) Ching, Bull. Fan Mem. Inst. Biol. 8: 206. 1938; Holttum, Dansk Bot. Ark. 20: 22. 1961; Holttum, Dansk Bot. Ark 23: 233. 1965. – Polypodium dentatum Forssk., Fl. Aegypt.-Arab.: 185. 1775. – Thelypteris dentata (Forssk.) St. John, Amer. Fern J. 26: 44. 1966; Tagawa & K.Iwats., SouthE. Asian Stud. 3(3): 79. 1965; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 65. 1967; Tagawa & K.Iwats., Fl. Thailand 3: 427. 1988. – Christella dentata (Forssk.) Brownsey & Jermy, Brit. Fern Gaz. 10: 338. 1973; Holttum, Kew Bull. 31: 314. 1976; Holttum, Fl. Males., Ser. II, Pterid. 1: 557, f. 1p & 20a. 1982 [‘1981’]; Boonkerd & Pollawatn, Pterid. Thailand: 220. 2000. – Type: Forsskal, Arabia (C).

Cyclosorus subpubescens auct. non (Blume) Ching: Holttum, Rev. Fl. Malaya ed. 1, 2: 273, f. 157. 1955 [‘1954’].

Description

Rhizome short, erect, ascending, or shortly creeping, with a tuft of fronds; scales narrow, about 8 by 1.5 mm, pale brown, with few hairs at margin. Stipes 13–30(–51) cm long, bearing reduced pinnae on upper portion, scaly at base, hairy throughout. Laminae narrowly oblong, acute at apex, gradually narrowing downwards, 30–75(–90) by 8.5–26.5 cm; lateral pinnae 12–25 pairs, patent to ascending, sessile, linear-lanceolate, more or less auricled at base, gradually narrowing towards long-acuminate apex, 4–14 by 1–2 cm, lobed 1/3 to 2/3 way to costa; lower pinnae hardly to gradually becoming smaller downwards but rarely reduced to mere auricles; segments oblong-subdeltoid, oblique, rounded at apex, entire; herbaceous to softly papyraceous, yellow-green to green, densely pubescent on both surfaces, not glandular or with extremely sparse tiny yellow glands; basal veinlets and basal second anterior ones uniting below callous-membrane. Sori medial, round; indusia large, densely hairy .

Distribution in Thailand

NORTHERN: Mae Hong Son, Chiang Mai, Chiang Rai, Lamphun, Lampang, Phrae, Tak, Phitsanulok; NORTH-EASTERN: Phetchabun, Loei, Khon Kaen; SOUTH-WESTERN: Kanchanaburi, Phetchaburi, Prachuap Khiri Khan; CENTRAL: Saraburi, Nakhon Nayok, Bangkok; SOUTH-EASTERN: Prachin Buri, Chanthaburi, Trat; PENINSULAR: Surat Thani, Phangnga, Nakhon Si Thammarat, Trang, Satun.

Wider Distribution

Pantropical.

Ecology

Usually on rather dry ground in light shade or in forests at low or medium altitudes.

Proposed IUCN Conservation Assessment

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

Voucher specimens - Thailand

Middleton et al. 4788, Phetchaburi, Kaeng Krachan National Park (E); Middleton et al. 5127, Loei, Phu Suan Sai National Park (E); Middleton et al. 5493, Trang, Ton Tok Waterfall (E).

Habit

Habit

Rhizome

Rhizome

Crozier

Crozier

Venation

Venation

Pinnae from above

Pinnae from above

Pinnae from beneath

Pinnae from beneath

Basal pinnae

Basal pinnae

Upper surface of rachis and pinnae

Upper surface of rachis and pinnae

Sori

Sori

Sori

Sori

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