Cycadales

Cycadales Temporal range: Early Permian–Recent PreЄ Є O S D C P T J K Pg N
Cycas rumphii with old and new male cones.
Scientific classification
Kingdom:	Plantae
Division:	Cycadophyta
Class:	Cycadopsida
Order:	Cycadales Pers. ex Bercht. & J. Presl
Families
Cycadaceae Cycas family Stangeriaceae Stangeria family Zamiaceae Zamia family
Approximate world distribution of living Cycadales

Cycadales is an order of seed plants that includes all the extant cycads. These plants typically have a stout and woody (ligneous) trunk with a crown of large, hard and stiff, evergreen leaves. They usually have pinnate leaves. The individual plants are either all male or all female (dioecious). Cycads vary in size from having trunks only a few centimeters to several meters tall. They typically grow very slowly and live very long, with some specimens known to be as much as 1,000 years old. Because of the superficial resemblance, they are sometimes confused with and mistaken for palms or ferns, but are only distantly related to either.

Cycadales are found across much of the subtropical and tropical parts of the world. They are found in South and Central America (where the greatest diversity occurs), Mexico, the Antilles, southeastern United States, Australia, Melanesia, Micronesia, Japan, China, Southeast Asia, India, Sri Lanka, Madagascar, and southern and tropical Africa, where at least 65 species occur. Some can survive in harsh semidesert climates (xerophytic), others in wet rain forest conditions, and some in both. Some can grow in sand or even on rock, some in oxygen-poor, swampy, bog-like soils rich in organic material, and some in both. Some are able to grow in full sun, some in full shade, and some in both. Some are salt tolerant (halophytes).