Cyathea glabra is a species of tree fern

Cyatheales

The order Cyatheales is a taxonomic division of the fern subclass, Cyatheatae, which includes the tree ferns. No clear morphological features characterize all of the Cyatheales, but DNA sequence data indicates that the order is monophyletic. Some species in the Cyatheales have tree-like growth...

 native to Borneo

Borneo

Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....

, western Java

Java

Java is an island of Indonesia. With a population of 135 million , it is the world's most populous island, and one of the most densely populated regions in the world. It is home to 60% of Indonesia's population. The Indonesian capital city, Jakarta, is in west Java...

, Sumatra

Sumatra

Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...

 and the Malay Peninsula

Malay Peninsula

The Malay Peninsula or Thai-Malay Peninsula is a peninsula in Southeast Asia. The land mass runs approximately north-south and, at its terminus, is the southern-most point of the Asian mainland...

, where it grows in lowland swamp

Swamp

A swamp is a wetland with some flooding of large areas of land by shallow bodies of water. A swamp generally has a large number of hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerates periodical inundation. The two main types of swamp are "true" or 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. Frond

Frond

The term frond refers to a large, divided leaf. In both common usage and botanical nomenclature, the leaves of ferns are referred to as fronds and some botanists restrict the term to this group...

s are bi- or tripinnate and 1-2 m in length. Characteristically of this species, the lowest pinnae may be significantly reduced. The stipe

Stipe (botany)

In botany, a stipe is a stalk that supports some other structure. The precise meaning is different depending on which taxonomic group is being described....

 is very dark and bears basal scale

Scale (zoology)

In most biological nomenclature, a scale is a small rigid plate that grows out of an animal's skin to provide protection. In lepidopteran species, scales are plates on the surface of the insect wing, and provide coloration...

s. These scales are dark, glossy and have a paler margin and fragile edges. Sori

Sorus

A sorus is a cluster of sporangia .In fungi and lichens, the sorus is surrounded by an external layer. In some red algae it may take the form of a depression into the thallus....

 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

Cyathea gigantea

Cyathea gigantea is a species of tree fern native to northeastern to southern India, Sri Lanka, Nepal to Myanmar, Thailand, Laos, Vietnam, the Malay Peninsula, as well as central Sumatra and western Java. It grows in moist open areas at an altitude of 600-1000 m. The trunk of this species is erect...

and appears to form part of a complex that also includes Cyathea podophylla

Cyathea podophylla

Cyathea podophylla is a widespread species of tree fern native to southern China, Taiwan, Vietnam, Laos, Thailand, Cambodia, and the Ryukyu Islands. It grows in forest by streams and in ravines at an altitude of 600-1000 m.-References:...

and Cyathea subdubia. Further study is needed to determine the nature of the relationship between these taxa

Taxon

|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...

.