Pteris longipes D.Don
Pteridaceae, subfamily Pteridoideae
Pteris longipes D.Don, Prodr. Fl. Nepal.: 15. 1825; Bedd., Handb. Ferns Brit. India: 115. 1883; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 154. 1940; Tagawa & K.Iwats., SouthE Asian Stud. 3(3): 83. 1965; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 81. 1967; Tagawa & K.Iwats., Fl. Thailand 3: 235. 1985; Boonkerd & Pollawatn, Pterid. Thailand: 129. 2000.
Rhizome erect, sometimes more than 10 cm tall, bearing a few fronds in a tuft, scaly at apex; scales about 7 by 0.8 mm, concolorously brown to darker, entire. Stipes up to 1 m long, stramineous throughout, glabrescent upwards. Laminae tripartite, middle branch longer, 35–55 cm long, up to 20 cm wide, deeply bipinnatisect, lateral branches smaller, up to 30 by 12 cm, bearing no secondary branch; pinnae linear-lanceolate, broadly cuneate at sessile base, caudately acuminate at apex, deeply pinnatisect nearly to costa, up to 10 cm long; fertile pinnae usually about 1.5 cm wide, sterile ones sometimes more than 2 cm; ultimate segments oblong, oblique, round to moderately acute at apex, serrate near tip, papyraceous, green, glandular hairy on upper surface; veins forked, all free, visible on both surfaces. Sori along margin of segment, from base nearly to apex; indusia brown, rather firm , up to 1 mm in breadth.
Distribution in Thailand
NORTHERN: Chiang Mai, Chiang Rai, Phrae, Tak; NORTH-EASTERN: Loei; EASTERN: Chaiyaphum; SOUTH-WESTERN: Kanchanaburi; SOUTH-EASTERN: Chanthaburi.
Distribution in Laos
N India, S China, Vietnam and Taiwan, southwards to the Philippines.
On mountain slopes usually in dense thickets in dry evergreen or lower montane forests at 700–1600 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. 4868, Chiang Mai, Doi Suthep-Doi Pui National Park (E); Van Beusekom et al. 4143, Chaiyaphum, Nam Phrom (P); Middleton et al. 4751, Kanchanaburi, Khao Laem National Park (E).
Voucher specimens - Laos
Poilane 28356, Champasak, Boloven Plateau (P).
Upper surface of lamina
Spines on costa above
Lower surface of lamina