Articles

Lygodium microphyllum (Cav.) R. Br.

Lygodium microphyllum (Cav.) R. Br.

Family

Schizaeaceae

Synonyms

Lygodium scandens Swartz (excl. syn. L.).

Vernacular Names

Malaysia Ribu-ribu, selada, kapai alus (Malay).
English Small leaved climbing fern, climbing maidenhair.
Indonesia Paku tali (General), paku kawat (Western Sumatra), paku hata leutik (Sundanese).
Thailand Kachot nuu (South-eastern), ree-bun paa dee, liphao yung (Peninsular).
Philippines Nito, nitong puti (Tagalog), nitong parang (Rizal).

Geographical Distributions

Lygodium microphyllum is distributed in tropical Africa, throughout Southeast Asia to Bangladesh and Hong Kong, Australia and Melanesia. It has naturalised in the southern United States as a nuisance.

Description

Lygodium microphyllum is a wide-creeping rhizome, dichotomously branched, measuring 2.5 mm in diametre and densely clothed with short brown-black hairs.

The juvenile leaves are small, commonly once dichotomous (the stipe is distinctly winged below the dichotomy) and each branch bears a 4-lobed leaflet which is not jointed at the base. The lobes are thin, measuring 3-5 cm x 5 mm, hairless and with crenately-toothed margins. The rachis of climbing leaves is hairless. It is commonly 2-3 m long and hardly measuring up to 1.5 mm in diametre. The primary branches are about 4 mm long while the secondary rachis-branches are pinnate, in all measuring up to about 15 cm long, with 3-6 stalked leaflets on each side (with stalks 2-4 mm long) and a similar or geminate leaflet. The leaflets are quite smooth, mostly ovate (sterile leaflets are often elongated with broader base on young plants), measuring 1-4(-6) cm x 6-18 mm and the margins of sterile ones are minutely crenate. A joint is always present at the base of the lamina, where the wing, as in other species, connects the stalk and the lamina. The fertile leaflets are usually shorter than the sterile ones but the lamina is hardly narrowed.

The Sorophores are 4-6 mm long. The spores are faintly granulose with a raised reticulum on the outer surface.

Ecology / Cultivation

Lygodium microphyllum grows in edges of secondary forests or is a climber on woody plants, bushes or on branches of tall trees, usually on dry slopes in open areas. It prefers clay soils and frequently forms thickets in open, swampy locations in regions with a dry season, from sea level up to 1300 m altitude. Its naturalisation in south-eastern Florida (United States) was first detected in 1965. Growing in tropical and subtropical wetlands and areas with moist soils, it is well-adapted to most parts of Florida where its current rate of spread and environmental impact are serious. It has become an aggressive invader of natural vegetation in many different habitats that are frequently dominated by the species. Currently, increasing densities and continued expansion of its distribution are observed. Moreover, it has become a serious fire hazard.

Line Drawing / Photograph

Lygodium_microphyllum

References

  1. Plant Resources of South-East Asia No. 15(2): Cryptogams: Ferns and fern allies.