''Zamites'' is a genus of fossil tree known from the
Mesozoic
The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceo ...
of
North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
,
Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...
and
India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
through the
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...
of North America. It was erected as a
form taxon for leaves that superficially resembled the extant
cycad
Cycads are seed plants that typically have a stout and woody (ligneous) trunk (botany), trunk with a crown (botany), crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants o ...
''
Zamia
''Zamia'' is a genus of cycad of the family Zamiaceae, native to North America from the United States (in Georgia and Florida) throughout the West Indies, Central America, and South America as far south as Bolivia. The genus is considered to be ...
'', however it is now believed to belong to a similar but phylogenetically different group, the cyacadeoids (
Bennettitales).
The fronds are linear or lanceolate in shape, and pinnately compound, with pinnae with parallel veins and smooth margins, and symmetrical and constricted at the base where they are attached obliquely to the upper surface of the
rachis. It has been interpreted as a Bennettitalean plant
[ in the family ]Williamsoniaceae
''Williamsoniaceae'' is a family within the Bennettitales, an extinct group of seed plants within the Cycadophyta subdivision. Members of this family are believed to have been around two meters tall and with widely serrate leaves along a central s ...
.''Zamites'' in IRMNG
/ref>
As explained by Zijlstra & van Konijnenburg-van Cittert (2020), the application of the genus name ''Zamites'' has over time drifted away from Brongniart's original concept to one where the species ''Z. gigas'' (Lindl. & Hutton) Morris has been treated as a ''de facto'' type, to the degree that none of Brongniart's four original species would now be assigned to it, instead being allocated to '' Otozamites'' and possibly elsewhere; this includes ''Z. bucklandii'', designated as the type of ''Zamites'' by Pfeiffer in a publication dating from 1871-1875, but now (as ''O. bucklandii'') the type of ''Otozamites''. Technically, unless otherwise addressed, this renders ''Otozamites'' a synonym of ''Zamites'' and would mean that ''Z. gigas'' plus all the species recognisably closer to it than to ''Z. bucklandii'' would require a new genus name. Zijlstra & van Konijnenburg-van Cittert chose to attempt to circumvent this situation by proposing that ''Zamites'' should be re-defined based on designating ''Z. gigas'' as a new type to replace ''Z. bucklandii'', a proposal that was recommended for acceptance by the Nomenclature Committee for Fossils in 2022.
Species
Species include:[
* '' Z. arcticus''
* '' Z. bayeri''
* '' Z. californica''
* '' Z. mariposana''
]
Distribution
Fossils of ''Zamites'' have been found in:[''Zamites'']
at Fossilworks
Fossilworks is a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database
The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals ...
.org
;Triassic (to Jurassic)
Antarctica, Austria, China, France, Germany, Honduras, Hungary, Italy, Japan, Mexico, Romania, Tajikistan, Ukraine, and the United States (New Mexico, North Carolina, Utah, Virginia, Virginia/North Carolina).
;Jurassic (to Cretaceous)
Antarctica, Argentina, Azerbaijan, Belarus, Chile, China, Colombia (Valle Alto Formation
The Valle Alto Formation ( es, FormaciĆ³n Valle Alto, Jva) is a geological formation of the Central Ranges of the Colombian Andes. The formation is composed of shales, sandstones and conglomerates and dates to the Late Jurassic period. Ammonit ...
, Caldas), Egypt, France, Georgia, Germany, Iran, Italy, Japan, Kazakhstan, Mexico, Mongolia, Portugal, Romania, the Russian Federation, Serbia and Montenegro, Switzerland, Tajikistan, Turkey, Ukraine, the United Kingdom, and the United States (Montana, Wyoming).
;Cretaceous
Canada (Alberta, British Columbia), Ecuador, Japan, Mexico, South Africa, Spain, and the United States (Montana, Virginia, Wyoming).
;Eocene
United States (California)
References
Bennettitales
Triassic first appearances
Triassic plants
Jurassic plants
Early Cretaceous plants
Late Cretaceous plants
Paleocene plants
Eocene plants
Eocene genus extinctions
Mesozoic trees
Mesozoic Antarctica
Mesozoic life of Asia
Mesozoic life of Europe
Mesozoic life of North America
Cretaceous Canada
Jurassic Mexico
Cretaceous Mexico
Jurassic United States
Cretaceous United States
Mesozoic life of South America
Prehistoric plants of South America
Jurassic Argentina
Fossils of Argentina
Jurassic Chile
Fossils of Chile
Jurassic Colombia
Fossils of Colombia
Cretaceous Ecuador
Fossils of Ecuador
Fossil taxa described in 1828
Fossils of Serbia
{{Paleobotany-stub