Cyathea alderwereltii 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...

 endemic

Endemic (ecology)

Endemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, all species of lemur are endemic to the...

 to Mount Sago

Mount Sago

Sago is a mountain in West Sumatra, Indonesia. It is near to the city of Payakumbuh and the town of Batusangkar....

 in central 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...

, where it is nevertheless abundant and grows in forest at an altitude of 1000-1500 m. It has an erect trunch which may be 4 m tall or more. 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 long. 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....

 of this species is spiny at the base and covered with scattered 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 that are dark brown, glossy, and have a narrow paler margin. 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 near the fertile pinnule midvein and are covered by small, brown scale-like indusia.

C. alderwereltii is named after Cornelis Rogier Willem Carel van Alderwerelt van Rosenburgh (1863-1936), a Dutch

Netherlands

The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

 pteridologist who worked extensively in the Sunda

Sundaland

Sundaland is a biogeographical region of Southeastern Asia which encompasses the areas of the Asian continental shelf that was exposed during the last ice age. It included the Malay Peninsula on the Asian mainland, as well as the large islands of Borneo, Java, and Sumatra and their surrounding...

region.