Atrypa
Encyclopedia
Atrypa also known as lamp shell is an extinct genus
of brachiopod
that lived from the Late Ordovician (444 million years ago) to the Carboniferous
(318 million years ago) and occurs abundantly as fossils in marine rocks. It has a wide distribution on all the continents except Antarctica.
The genus has distinctive concentric growth lines and is unusual in that in some Devonian
beds there are numerous remains of the pedicle
valve, but extremely few of the brachial
valve.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of brachiopod
Brachiopod
Brachiopods are a phylum of marine animals that have hard "valves" on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, while the front can be opened for feeding or closed for protection...
that lived from the Late Ordovician (444 million years ago) to the Carboniferous
Carboniferous
The Carboniferous is a geologic period and system that extends from the end of the Devonian Period, about 359.2 ± 2.5 Mya , to the beginning of the Permian Period, about 299.0 ± 0.8 Mya . The name is derived from the Latin word for coal, carbo. Carboniferous means "coal-bearing"...
(318 million years ago) and occurs abundantly as fossils in marine rocks. It has a wide distribution on all the continents except Antarctica.
The genus has distinctive concentric growth lines and is unusual in that in some Devonian
Devonian
The Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya , to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya...
beds there are numerous remains of the pedicle
Pedicle (zoology)
In zoology, the pedicle refers to a fleshy line brachiopods and some bivalve mollusks use to attach and anchor to a substrate. In brachiopods, the pedicle emerges from a pedicle opening. Some brachiopods do not have a functional pedicle, and thus do not have this pedicle opening....
valve, but extremely few of the brachial
Brachial
Brachial means "pertaining to the arm," and may refer to:*Brachial artery, in anatomy*Brachial valve, the upper valve in Brachiopods...
valve.
External links
- Atrypa in the Paleobiology DatabasePaleobiology Database' is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms.-History:The Paleobiology Database was founded in 2000. It has been funded by the National Science Foundation and the Australian Research Council...