Cyclosorus interruptus (Willd.) H.Ito




Cyclosorus interruptus (Willd.) H.Ito, Bot. Mag. Tokyo 51: 714. 1937, nom. tant.; Holttum, Fl. Males., Ser. II, Pterid., 1: 386, f. 1r, 7a–c. 1982 [‘1981’]; Boonkerd & Pollawatn, Pterid. Thailand: 223. 2000. – Pteris interrupta Willd., Phytogr. 1: 13, t. 10. 1794. – Thelypteris interrupta (Willd.) K.Iwats., J. Jap. Bot. 38: 314. 1963, nom. tant. ; Fosberg & Sachet, Smithsonian Contr. Bot. 8: 8. 1972; Tagawa & K.Iwats., Fl. Thailand 3: 400, f. 38.8–9. 1988. Type: Klein, S. India (B; Herb. Willd. 19, 770).

Cyclosorus gongylodes auct. non (Schkuhr) Link: Holttum, Rev. Fl. Malaya ed. 1, 2: 261, f. 148. 1955 [‘1954’]; Holttum, Dansk Bot. Ark. 20: 23. 1961.

Thelypteris goggilodus auct. non (Schkuhr) Small: Tagawa & K.Iwats. SouthE. Asian Stud. 3(3): 79. 1965; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 68. 1967.


Rhizome long creeping, up to 4 mm diam., usually dark; scales caducous, subdeltoid, pale brown, thin, up to 2.5 by 1.5 mm, glabrous. Stipes 24–70 cm long, stramineous with dark base, glabrous. Laminae stiff, oblong-lanceolate, acute at apex, 22.5–60 by 8–22 cm, 14–25 pairs of pinnae; basal pinnae hardly reduced, larger pinnae sessile, linear-lanceolate, gradually narrowing towards acute apex, rounded at base, 6–15 by 0.9–1.8 cm, lobed to 1/4 way towards costa, 1.8–3.5 cm apart; costa hairy, rarely glabrous, bearing scales sparsely; segments oblong-subdeltoid with aciculate apex; pubescent on lower surface, sometimes only with minute glands on veins so appearing glabrous; veins pinnate, usually 1.5 pairs of basal veinlets uniting with those of the adjacent groups, hairy as well as glandular. Sori confined to segments, usually confluent at maturity; indusia glabrous or hairy, caducous .

Distribution in Thailand

NORTHERN: Chiang Mai, Phayao, Lampang; SOUTH-WESTERN: Kanchanaburi, Phetchaburi, Prachuap Khiri Khan; CENTRAL: Bangkok; PENINSULAR: Surat Thani, Phuket, Krabi, Nakhon Si Thammarat, Phatthalung, Songkhla, Yala.

Distribution in Laos


Distribution in Cambodia

Kampot, Kompong Speu, Siem Reap

Wider Distribution



On grassy banks along streams or in open marshy places at low altitudes.

Similar species

Cyclosorus aridus (D.Don) Ching

IUCN Conservation Assessment

Least Concern (LC) as listed on the IUCN Red List at

Voucher specimens - Thailand

Middleton et al. 4782, Kanchanaburi, Thong Pha Phum National Park (E); Newman et al. 1141, Prachuap Khiri Khan, Sam Roi Yot National Park (E).

Voucher specimens - Laos

Maxwell 07-169, Savannakhet (CMU)





Unfurling fromd

Unfurling fromd

Young sori

Young sori



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