''Pecopteris'' is a very common

form genus Form classification is the classification of organisms based on their morphology, which does not necessarily reflect their biological relationships. Form classification, generally restricted to palaeontology, reflects uncertainty; the goal of sc ...

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

. Most ''Pecopteris'' leaves and fronds are associated with the marattialean tree fern ''

Psaronius ''Psaronius'' is an extinct genus Marattiales, marattialean tree fern which grew to 10m in height, and is associated with leaves of the Form taxon, organ genus ''Pecopteris'' and other extinct tree ferns. Originally, ''Psaronius'' was a name for ...

''. However, ''Pecopteris''-type foliage also is borne on several filicalean ferns, and at least one

seed fern In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be sown, which may include seed and husk or tuber. Seeds are the ...

. Pecopteris first appeared in the

Devonian The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian per ...

period, but flourished in the

Carboniferous The Carboniferous ( ) is a Geologic time scale, geologic period and System (stratigraphy), system of the Paleozoic era (geology), era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the ...

, especially the

Pennsylvanian Pennsylvanian may refer to: * A person or thing from Pennsylvania * Pennsylvanian (geology) The Pennsylvanian ( , also known as Upper Carboniferous or Late Carboniferous) is, on the International Commission on Stratigraphy, ICS geologic timesc ...

. Plants bearing these leaves became extinct in the

Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the s ...

period, due to swamps disappearing and temperatures on Earth dropping.

Etymology

''Pecopteris'' is derived from the Greek ''pekin'', (to comb), and ''pteris'', (a fern). This is because the leaflets of ''Pecopteris'' fronds are arranged like the teeth on a comb.

Species

As of 1997, there have been 250-300 species assigned to ''Pecopteris''. In

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

, fossil of

''Pecopteris'' was located in outcrop ''Morro Papalé'' in the city of

Mariana Pimentel Mariana Pimentel is a municipality in the state of Rio Grande do Sul, Brazil. It is located approximately 75 km from the state's capital, Porto Alegre. Geography Mariana Pimentel belongs to Porto Alegre Metropolitan Mesoregion and to Porto ...

. They are in the geopark Paleorrota in

Rio Bonito Formation The Rio Bonito Formation is a geological formation of the Paraná and Pelotas Basins of Permian age. It is represented by a succession of cyclic sedimentary packages of sandstones, siltstones and shales which bear extensive deposits of coal that ...

and date from

Sakmarian In the geologic timescale, the Sakmarian is an age or stage of the Permian period. It is a subdivision of the Cisuralian Epoch or Series. The Sakmarian lasted between 293.52 and million years ago (Ma). It was preceded by the Asselian and fo ...

.Afloramento Morro do Papaléo, Mariana Pimentel, RS
/ref> Image:Pecopteris unita.JPG, ''Pecopteris unita'' File:Pecopteris PAMuseum.jpg, ''Pecopteris'' on display at the

State Museum of Pennsylvania The State Museum of Pennsylvania is a non-profit history museum at 300 North Street in downtown Harrisburg, Pennsylvania, United States. It is run by the Pennsylvania Historical and Museum Commission to preserve and interpret the Commonwealth's h ...

File:Exhibit Museum of Natural History, Ann Arbor - IMG 9198.JPG, ''Pecopteris'' in the Exhibit Museum of Natural History, Ann Arbor

References

External links

Prehistoric plant genera Devonian plants Carboniferous plants Fossils of Georgia (U.S. state) Paleozoic life of New Brunswick Paleozoic life of Nova Scotia Paleozoic life of Prince Edward Island Prehistoric plants of North America {{Carboniferous-plant-stub