Family

Polypodiaceae

Nomenclature

Loxogramme lankokiensis (Rosenst.) C.Chr., Index Filic. Suppl. III: 125. 1934; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 464. 1941; Tagawa & K.Iwats., Acta Phytotax. Geobot. 24: 60. 1969; Tagawa & K.Iwats., Fl. Thailand 3: 580. 1989; Boonkerd & Pollawatn, Pterid. Thailand: 278. 2000; Newman et al., Checkl. Vasc. Pl. Lao PDR: 30. 2007. – Polypodium lankokiense Rosenst., Med. Rijks. Herb. 5: 31. 1917.

Loxogramme microphylla C.Chr., Dansk Bot. Ark. 6: 48, pl. 3, f. 6. 1929.

Description

Rhizome long creeping, slender, about 0.5 mm diam., densely scaly throughout; scales gradually narrowing from round base towards subulate apex, about 2 by up to 0.5 mm, entire, thin, brown, distinctly clathrate. Fronds remote, dimorphic. Sterile fronds orbicular, with stipes up to 2 mm long, about 1 cm long, nearly as long as wide, midrib visible only at the base, raised on upper surface, veins quite invisible; chartaceous. Fertile fronds with short stipes bearing narrow wings, oblanceolate, broadest at 1/5–1/7 way from apex, acute at apex, attenuate towards base, about 3 cm long including indistinct stipes, up to 5 mm broad; midrib distinct on lower half, margin a little involved. Sori oblique, confluent with the next ones at maturity, up to 7 by 1 mm.

Distribution in Thailand

NORTHERN: Nan; NORTH-EASTERN: Loei.

Distribution in Laos

Savannakhet.

Wider Distribution

N Vietnam and Laos.

Ecology

On stones in river-bed or epiphytic on trees in hill evergreen forests at 740–900 m alt.

Proposed IUCN Conservation Assessment

Least Concern (LC). Although rarely collected this species is widespread and not under any known threat.

Notes

This is a dwarf species of Loxogramme with dimorphic fronds. In appearance L. lankokiensis resembles L. conferta but is distinct from the latter in moderately acute apex of fronds, shortly stalked frond; smaller size, and finely clathrate brown rhizome scales.

Voucher specimens - Thailand

La-Ongsri & Norsaengsri 1808, Nan (QBG).