''Atrypa'' is a genus of

brachiopod Brachiopods (), phylum Brachiopoda, are a phylum of trochozoan animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, w ...

with shells round to short egg-shaped, covered with many fine radial ridges (or costae), that split further out and growth lines perpendicular to the costae and 2-3 times wider spaced. The pedunculate valve is a little convex, but tends to level out or even become slightly concave toward the anterior margin (that is: opposite hinge and pedicle). The brachial valve is highly convex. There is no interarea (that is a flat area bordering the hinge line approximately perpendicular with the rest of the valve) in either valve. ''Atrypa'' was a cosmopolitan and occurred from the late Lower Silurian (

Telychian In the geologic timescale, the Telychian is the age of the Llandovery Epoch of the Silurian Period of the Paleozoic Era of the Phanerozoic Eon. The Telychian Age was between 438.5 ± 1.2 million years ago (Ma) and 433.4 ± 0.8 Ma. The Telych ...

) to the early Upper Devonian (

Frasnian The Frasnian is one of two faunal stages in the Late Devonian Period. It lasted from million years ago to million years ago. It was preceded by the Givetian Stage and followed by the Famennian Stage. Major reef-building was under way during th ...

). Other sources expand the range from the

Late Ordovician The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period million years ago (Mya) to the start of the Silurian Period Mya. ...

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 ...

, approximately from 449 to 336 Ma.''Atrypa''
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 A proposed new species, ''A. harrisi'', was found in the trilobite-rich

Floresta Formation The Floresta Formation ( es, Formación Floresta, Df) is a geological formation of the Altiplano Cundiboyacense in the Eastern Ranges of the Colombian Andes. The sequence of siltstones, shales, coquinas and sandstone beds dates to the Devonia ...

in Boyacá, Colombia.Floresta Series Fauna
at

.org

Reassigned species

As ''Atrypa'' was erected early on, many species have been reassigned since.

Organic content of ''Atrypa'' fossils

In some fossil material, organic compounds may be preserved. Only the more stable

amino acids Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...

tend to be preserved in very old fossils. In specimens of ''Atrypa reticularis'' from the Wenlock Shales (Lower Silurian),

alanine Alanine (symbol Ala or A), or α-alanine, is an α-amino acid that is used in the biosynthesis of proteins. It contains an amine group and a carboxylic acid group, both attached to the central carbon atom which also carries a methyl group side ...

glycine Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid (carbamic acid is unstable), with the chemical formula NH2‐ CH2‐ COOH. Glycine is one of the proteinogeni ...

, glutamic acid,

leucine Leucine (symbol Leu or L) is an essential amino acid that is used in the biosynthesis of proteins. Leucine is an α-amino acid, meaning it contains an α- amino group (which is in the protonated −NH3+ form under biological conditions), an α- ...

, isoleucine, proline,

valine Valine (symbol Val or V) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α- amino group (which is in the protonated −NH3+ form under biological conditions), an α- carboxylic acid group (which is in the deprotona ...

, and aspartic acid have been found.

Gallery

File:Atrypa devoniana pedunculate Rockford IO CRF.jpg, ''Atrypa devoniana'', pedicle valve File:Atrypa devoniana brachial Rockford IO CRF.jpg, ''Atrypa devoniana'', brachial valve File:Atrypa devoniana anterior Rockford IO CRF.jpg, ''Atrypa devoniana'', anterior view File:Atrypa devoniana posterior Rockford IO CRF.jpg, ''Atrypa devoniana'', posterior view File:Atrypa devoniana lateral Rochford IO CRF.jpg, ''Atrypa devoniana'', lateral view File:Atrypid dorsal.jpg, ''Atrypa'' sp.; Couvinian (Middle Devonian); El Pical, Leon, Spain. Eroded to show spiralia on the right.

References

Prehistoric brachiopod genera Silurian brachiopods Devonian brachiopods Paleozoic animals of Africa Paleozoic animals of Asia Paleozoic brachiopods of Oceania Paleozoic animals of Europe Paleozoic animals of North America Paleozoic brachiopods of South America Devonian Colombia Fossils of Afghanistan Fossils of Australia Fossils of Austria Fossils of Belarus Fossils of Belgium Fossils of Canada Fossils of China Fossils of Colombia Fossils of the Czech Republic Fossils of Estonia Fossils of France Fossils of Germany Fossils of Greenland Fossils of India Fossils of Iran Fossils of Ireland Fossils of Italy Fossils of Japan Fossils of Kazakhstan Fossils of Latvia Fossils of Lithuania Fossils of Mexico Fossils of Mongolia Fossils of Morocco Fossils of Myanmar Fossils of Norway Fossils of Peru Fossils of Poland Fossils of Russia Fossils of Spain Fossils of Sweden Fossils of Tajikistan Fossils of Thailand Fossils of Ukraine Fossils of the United States Fossils of Uzbekistan Fossils of Venezuela Fossils of Vietnam Silurian first appearances Frasnian extinctions Fossils of Georgia (U.S. state) Jeffersonville Limestone Paleontology in New Hampshire Paleozoic life of Ontario Paleozoic life of Alberta Paleozoic life of British Columbia Floresta Formation Paleozoic life of Manitoba Paleozoic life of New Brunswick Paleozoic life of the Northwest Territories Paleozoic life of Nova Scotia Paleozoic life of Nunavut Paleozoic life of Quebec Paleozoic life of Yukon Fossil taxa described in 1828 {{Brachiopod-stub

Reassigned species

Organic content of ''Atrypa'' fossils

Gallery

See also

References