Question: Which is a type of fern, Cibotium or Ecballium?
Context: Cibotium regale, common name royal cibotium or royal Mexican tree fern, is a species of tropical tree fern belonging to the family Cibotiaceae. Cibotium cumingii is a species of tree fern, of the genus "Cibotium".  It is named after the 19th century collector, Hugh Cuming.  Its apex and young fronds are covered with reddish hairs.  It can be found growing in open forest or in hilly areas in the Philippines and in Taiwan. The tree ferns are the ferns that grow with a trunk elevating the fronds above ground level.  Most tree ferns are members of the "core tree ferns", belonging to the families Dicksoniaceae, Metaxyaceae, and Cibotiaceae in the order Cyatheales.  In addition to those families, many ferns in other groups may be considered tree ferns, such as several ferns in the family Osmundaceae, which can achieve short trunks under a metre tall, and particularly ferns in the genus "Cibotium", which can grow ten metres tall.  Fern species with short trunks in the genera "Blechnum, Calochleana, Cnemedaria, Culcita" (Europe's only tree fern), "Cystodium, Leptopteris, Lophosoria, Sadleria, Thyrsopteris" and "Todea" could also be considered tree ferns in a liberal interpretation of the term. Georg Friedrich Kaulfuss (8 April 1786 – 9 December 1830) was a professor at Halle.  He described the pteridophytes collected by Adalbert von Chamisso, and named the fern "Cibotium chamissoi" after him.  The genus "Kaulfussia" is named for Kaulfuss. Lygodium microphyllum (commonly known as, variously, climbing maidenhair fern, Old World climbing fern, small-leaf climbing fern, or snake fern ) is a climbing fern originating in tropical Africa, South East Asia, Melanesia and Australia.  It is an invasive weed in the US States of Florida and Alabama where it invades open forest and wetland areas.  The type specimen was collected in the vicinity of Nabúa, on the Island of Luzon in the Philippines by Luis Née. Cibotium menziesii, the hāpuʻ u ʻ iʻ i or Hawaiian tree fern,) is a species of tree fern that is endemic to the islands of Hawaiʻ i.  It is named after the Scottish naturalist Archibald Menzies.  It is also known as the male tree fern, and "Cibotium glaucum" is deemed the female tree fern due to differences in color. Cibotium barometz, the golden chicken fern or woolly fern, is a species of tree fern native to parts of China and to the western part of the Malay Peninsula.  The fern's woolly rhizome was thought to be the inspiration for the mythical "Vegetable Lamb of Tartary". Ecballium is a genus of flowering plants in the family Cucurbitaceae containing a single species, Ecballium elaterium, also called the squirting cucumber or exploding cucumber (but not to be confused with "Cyclanthera explodens").  It gets its unusual name from the fact that, when ripe, it squirts a stream of mucilaginous liquid containing its seeds, which can be seen with the naked eye.  It is thus considered to have rapid plant movement. Cibotium (from the Greek "kibootion", meaning chest or box) is a genus of 11 species of tropical tree fern—subject to much confusion and revision—distributed fairly narrowly in Hawaiʻ i (four species, plus a hybrid, collectively known as hāpuʻ u), Southeast Asia (five species), and the cloud forests of Central America and Mexico (two species).  Some of the species currently listed in the literature seem to be synonyms or local-variant subspecies. " Cibotium glaucum", from Hawaiʻ i, is the most frequently encountered "Cibotium" species in the horticultural trade, together with its sibling species "Cibotium chamissoi" and the potentially huge "Cibotium menziesii".  The remaining Hawaiian "Cibotium", "C. nealiae", is a 1 m dwarf variety, restricted to the island of Kauaʻ i that is never seen in the horticultural trade.  Precise identification of "Cibotium" species is difficult, although all have shiny and rather waxy fronds when viewed from above, with varying degrees of powdery-pale blush when seen from underneath.  The natural habitat of "Cibotium" is among the dripping trees and stream gullies of the rainforests on Hawaiʻ i's windward volcanic slopes. Cibotium schiedei, common name Mexican tree fern, is a species of tree fern, of the genus "Cibotium".
Answer: Cibotium