''Claraia'' is an extinct
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
of
scallop-like
bivalve molluscs that lived from the
Capitanian
In the geologic timescale, the Capitanian is an age or stage of the Permian. It is also the uppermost or latest of three subdivisions of the Guadalupian Epoch or Series. The Capitanian lasted between and million years ago. It was preceded by ...
stage of the
Late Permian
Late may refer to:
* LATE, an acronym which could stand for:
** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia
** Local-authority trading enterprise, a New Zealand business law
** Local average treatment effect, ...
to the
Anisian
In the geologic timescale, the Anisian is the lower stage or earliest age of the Middle Triassic series or epoch and lasted from million years ago until million years ago. The Anisian Age succeeds the Olenekian Age (part of the Lower Triassic ...
stage of the
Middle Triassic
In the geologic timescale, the Middle Triassic is the second of three epochs of the Triassic period or the middle of three series in which the Triassic system is divided in chronostratigraphy. The Middle Triassic spans the time between Ma and ...
, 266-237 million years ago. Fossils have been found worldwide in North America, Europe, Asia, Africa, and Australia. These are common fossils subsequent to the Permian-Triassic boundary, suggesting that the genus experienced rapid diversification during and after the
Permian–Triassic extinction event
The Permian–Triassic (P–T, P–Tr) extinction event, also known as the Latest Permian extinction event, the End-Permian Extinction and colloquially as the Great Dying, formed the boundary between the Permian and Triassic geologic periods, as ...
, around 251.4 million years ago.
Ecology
''Claraia'' may have been an
opportunistic
Opportunism is the practice of taking advantage of circumstances – with little regard for principles or with what the consequences are for others. Opportunist actions are expedient actions guided primarily by self-interested motives. The term ...
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
that filled the
niche
Niche may refer to:
Science
*Developmental niche, a concept for understanding the cultural context of child development
*Ecological niche, a term describing the relational position of an organism's species
*Niche differentiation, in ecology, the ...
of many
benthic invertebrate
Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...
s such as
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 ...
s that were heavily impacted by the extinction. A narrowing of the
byssal notch and a trend towards a smoother shell in species of ''Claraia'' over time may have led to increased mobility. This increase in mobility may have been an advantage over more
sessile
Sessility, or sessile, may refer to:
* Sessility (motility), organisms which are not able to move about
* Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant
* Sessility (medicine), tumors and polyps that ...
animals during the extinction event.
[Feng, Qinglai; Gu, Songzhu; He, Weihong; Meng, Youyan; Weldon, Elisabeth A.; Wu, Shunbao; & Zhang, Fan (2007) A Late Permian to Early Triassic bivalve fauna from the Dongpan Section, Southern Guangxi, South China. '']Journal of Paleontology
The ''Journal of Paleontology'' is a peer-reviewed scientific journal covering the field of paleontology. It is published by the Paleontological Society.
Indexing
The ''Journal of Paleontology'' is indexed in:
*BIOSIS Previews
*Science Citation ...
'' 81: 1009–1019. It is thought to have lived in
anoxic waters
Anoxic waters are areas of sea water, fresh water, or groundwater that are depleted of dissolved oxygen. The US Geological Survey defines anoxic groundwater as those with dissolved oxygen concentration of less than 0.5 milligrams per litre. Anoxic ...
at great depths, and therefore may have been better adapted for the
anoxic event
Oceanic anoxic events or anoxic events ( anoxia conditions) describe periods wherein large expanses of Earth's oceans were depleted of dissolved oxygen (O2), creating toxic, euxinic (anoxic and sulfidic) waters. Although anoxic events have not ...
that may have occurred during the Permian–Triassic extinction event.
References
External links
Claraiaat
The Paleobiology Database
The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms.
History
The Paleobiology Database (PBDB) originated in the NCEAS-funded Phanerozoic Marine Pale ...
Pectinida
Prehistoric bivalve genera
Permian bivalves
Triassic bivalves
Permian animals of Africa
Permian animals of Asia
Permian animals of Oceania
Permian animals of Europe
Permian animals of North America
Triassic animals of Africa
Triassic animals of Asia
Triassic animals of Oceania
Triassic animals of Europe
Triassic animals of North America
Capitanian genus first appearances
Wuchiapingian genera
Changhsingian genera
Induan genera
Olenekian genera
Anisian genus extinctions
Anisian life
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