Gymnosphaera glabra

Cyathea glabra
Scientific classification
Kingdom:	Plantae
Division:	Pteridophyta
Class:	Pteridopsida
Order:	Cyatheales
Family:	Cyatheaceae
Genus:	Cyathea
Subgenus:	Cyathea
Section:	Alsophila
Species:	C. glabra
Binomial name
Cyathea glabra (Blume) Copeland, 1909
Synonyms
Alsophila glabra (Blume) W. J. Hooker, 1844 Alsophila reducta Alderwerelt van Rosenburgh, 1918 Cyathea reducta (Alderwerelt van Rosenburgh) Domin, 1930 Gymnosphaera glabra Blume, 1828 Polypodium giganteum Wallich, 1828 (non Polypodium giganteum Desvaux, 1827)

Cyathea glabra is a species of tree fern native to Borneo, western Java, Sumatra and the Malay Peninsula, where it grows in lowland swamp forest and montane forest at an elevation of up to 1500 m. The trunk of this plant is erect and 2–4 m tall. Fronds are bi- or tripinnate and 1–2 m in length. Characteristically of this species, the lowest pinnae may be significantly reduced. The stipe is very dark and bears basal scales. These scales are dark, glossy and have a paler margin and fragile edges. Sori are produced in groups of one to three on fertile pinnule veins. They lack indusia.

Large and Braggins (2004) note that C. glabra is very similar to Cyathea gigantea and appears to form part of a complex that also includes Cyathea podophylla and Cyathea subdubia. Further study is needed to determine the nature of the relationship between these taxa.

References

• Braggins, John E. & Large, Mark F. 2004. Tree Ferns. Timber Press, Inc., pp. 136–137. ISBN 0-88192-630-2
• The International Plant Names Index: Cyathea glabra