''Pecopteris'' is a very common form genus of

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

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

Psaronius ''Psaronius'' was a 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 the petrified ...

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

seed fern A seed is an Plant embryogenesis, embryonic plant enclosed in a testa (botany), protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, includ ...

. Pecopteris first appeared in the

Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, whe ...

period, but flourished in the

Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carbonifero ...

, especially the Pennsylvanian. Plants bearing these leaves became extinct in the

Permian The Permian ( ) is a geologic period and 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 251.9 Mya. It is the last period of the Paleoz ...

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 ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

, fossil of form genus ''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. 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 followed by t ...

.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 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 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 {{paleobotany-stub