Family

Gleicheniaceae

Nomenclature

Sticherus truncatus (Willd.) Nakai, Bull. Natl. Sci. Mus. 29: 20. 1950. – Gleichenia truncata (Willd.) Spreng., Syst. Veg. 4: 25. 1827; Holttum, Fl. Males., Ser. II, Pterid. 1: 20, f. 7a–b & 9. 1959; Tagawa & K.Iwats., Fl. Thailand 3: 53. 1979; Boonkerd & Pollawatn, Pterid. Thailand: 81. 2000. – Mertensia truncata Willd., Kongl. Vetensk. Acad. Nya Handl. 25: 169, t. 5, f. A. 1804.

Mertensia laevigata Willd., Sp. Pl. ed. 4, 5(1–2): 75. 1810. – Gleichenia laevigata (Willd.) Hook., Sp. Fil. 1: 10. 1844; Christ, Bat. Tidsskr. 24: 112. 1901; C.Chr., Bot. Tidsskr. 32: 349. 1916; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 51. 1939; Holttum, Rev. Fl. Malaya ed. 1, 2: 71. 1955 [‘1954’].

Description

Terrestrial. Rhizome dichotomously branched, near the apex protected by peltate scales. Fronds of mature plants usually with indefinite growth in length, bearing primary branches in pairs. Main rachis high-climbing; resting buds covered with brown, short-fringed scales; stipular leaflets at base of primary branch and at its first fork, deltoid, deeply lobed or the basal lobes again lobed, up to 2.7 cm long; rachis branches repeatedly forked, all branches, except the basal segments, leafy throughout, each branch 7.5–12 cm long; lobes patent, adnate at base, hardly decurrent to the next ones, usually irregular in length even on the same branch, up to 3.5 cm long, 2 mm broad, the margin entire, revolute, not glaucous beneath; veins free. Sori exindusiate, with 3–5 sporangia, surrounded by stellate hairs, medial .

Distribution in Thailand

SOUTH-EASTERN: Trat.

Distribution in Cambodia

Kampot.

Wider Distribution

Vietnam and throughout Malesia.

Ecology

Climbing ferns growing on stream banks at about 50–600 m alt.

Proposed IUCN Conservation Assessment

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

Notes

The record for this species in Laos in Fl. Indo-Chine would appear to be a mistake as Blao is in Vietnam, not Laos.