Family

Pteridaceae, subfamily Cheilanthoideae

Nomenclature

Calciphilopteris ludens (Wall. ex Hook.) Yesilyurt & H.Schneid., Phytotaxa 7: 56. 2010. – Pteris ludens Wall. ex Hook., Sp. Fil. 2: 210. 1858. – Doryopteris ludens (Wall. ex Hook.) J.Sm., Hist. Fil.: 289. 1875; Bedd., Handb. Ferns Brit. India: 120, f. 61. 1883; C.Chr.,Contr. U.S. Natl. Herb. 26: 333. 1931; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 176, f. 21, 1. 1940; Tryon, Contr. Gray Herb. 143: 60, pl. 8 B, map 11. 1942; Holttum, Rev. Fl. Malaya ed. 1, 2: 594, f. 349. 1955 [‘1954’]; Holttum, Dansk Bot. Ark. 23: 243. 1965; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 109. 1967; Tagawa & K.Iwats., Fl. Thailand 3: 197. 1985; Boonkerd & Pollawatn, Pterid. Thailand: 101, 123. 2000.

Description

Terrestrial or lithophytic. Rhizome long creeping, about 3 mm diam., bearing distant stipes, covered with scales; scales linear-subulate, 3–4 mm long, distinctly bicoloured, entire, glabrous. Stipes nearly black, polished, scaly at base, sparsely hairy upwards, 20–50 cm long. Frond dimorphic; sterile lamina smaller and less lobed, 15–20 by 10–20 cm, pinnatifid with usually 5 lobes, the apical lobe the largest, or in larger fronds with a few pairs of lobes, the basal lobes the largest, with a few secondary lobes; lobes oblong-subdeltoid to triangular, acute at apex, entire or slightly waved, with distinct main veins; veins copiously reticulate without included veinlets; papyraceous, glabrous. Fertile lamina up to 20 cm long and wide, subdeltoid in outline, deeply pinnatisect, usually with three pairs of lobes, the lowest pair the largest, usually with one or two secondary lobes; lobes linear or linear subtriangular, caudately acuminate at apex, entire, 1–2 cm broad, up to 10 cm long; main veins distinct, black. Sori continuous along the margin of fronds, a very short interruption at apices of lobes, covered by thin reflexed margin .

Distribution in Thailand

NORTHERN: Mae Hong Son, Chiang Mai, Chiang Rai, Lampang, Phrae, Tak, Nakhon Sawan; NORTH-EASTERN: Loei; EASTERN: Nakhon Ratchasima; SOUTH-WESTERN: Kanchanaburi, Ratchaburi, Phetchaburi, Prachuap Khiri Khan; CENTRAL: Nakhon Nayok; SOUTH-EASTERN: Chon Buri, Chanthaburi; PENINSULAR: Chumphon, Surat Thani, Phangnga, Krabi, Nakhon Si Thammarat, Trang, Satun, Yala.

Distribution in Laos

Champasak, Luang Phrabang.

Distribution in Cambodia

Kampot, Mondulkiri.

Wider Distribution

N India, S China, Indochina and throughout Malesia.

Ecology

Terrestrial in tropical or evergreen forests at low or medium altitudes, or lithophytic especially on limestone rocks.

Proposed IUCN Conservation Assessment

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

Voucher specimens - Thailand

Middleton et al. 4261, Prachuap Khiri Khan, Khao Sam Roi Yot National Park (E).

Voucher specimens - Laos

Maxwell 98-425, Champasak (CMU).

Voucher specimens - Cambodia

Bouillod s.n., Cambodia Unspecified (P); Long et al. CL350, Mondulkiri (P).