''Texigryphaea'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

oyster Oyster is the common name for a number of different families of salt-water bivalve molluscs that live in marine or brackish habitats. In some species, the valves are highly calcified, and many are somewhat irregular in shape. Many, but not al ...

belonging to the order

Ostreida The order Ostreida includes the true oysters. One superfamily (Ostreoidea) and two extant families are recognised within it. The two families are Ostreidae, the true oysters, and Gryphaeidae The Gryphaeidae, common name the foam oysters or ...

and family

Gryphaeidae The Gryphaeidae, common name the foam oysters or honeycomb oysters, are a family of marine bivalve mollusks. This family of bivalves is very well represented in the fossil record, however the number of living species is very few. All species ...

. It dates to the

Albian The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous Epoch/Series. Its approximate time range is 113.0 ± 1.0 Ma to 100.5 ± 0.9 M ...

Cenomanian The Cenomanian is, in the ICS' geological timescale, the oldest or earliest age of the Late Cretaceous Epoch or the lowest stage of the Upper Cretaceous Series. An age is a unit of geochronology; it is a unit of time; the stage is a unit in the s ...

Ages Ages may refer to: *Advanced glycation end-products, known as AGEs *Ages, Kentucky, census-designated place, United States * ''Ages'' (album) by German electronic musician Edgar Froese *The geologic time scale, a system of chronological measuremen ...

of the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...

period Period may refer to: Common uses * Era, a length or span of time * Full stop (or period), a punctuation mark Arts, entertainment, and media * Period (music), a concept in musical composition * Periodic sentence (or rhetorical period), a concept ...

and is primarily found in Texas and the southern Western Interior of North America. However, specimens have been identified from northern Spain. The genus were free-living

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "t ...

oysters that were often the dominant species in late Albian

biomes A biome () is a biogeographical unit consisting of a biological community that has formed in response to the physical environment in which they are found and a shared regional climate. Biomes may span more than one continent. Biome is a broader ...

of the

Western Interior Seaway The Western Interior Seaway (also called the Cretaceous Seaway, the Niobraran Sea, the North American Inland Sea, and the Western Interior Sea) was a large inland sea that split the continent of North America into two landmasses. The ancient sea, ...

. Some limestone beds of the Muleros Formation near

El Paso, Texas El Paso (; "the pass") is a city in and the county seat, seat of El Paso County, Texas, El Paso County in the western corner of the U.S. state of Texas. The 2020 population of the city from the United States Census Bureau, U.S. Census Bureau w ...

, consist almost entirely of fossil fragments of ''T. washitaensis''. Most species preferred soft substrates in quiet environments, but ''T. navia'' was adapted to firmer substrates in more energetic environments. The genus differs from

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The J ...

Gryphaeidae in possessing a vesicular shell structure and chomata (a fine set of parallel ribs found on the inner valves). ''T. tucumcarii'' is considered to be a synonym for ''T. pitcheri''.

Selected species

* '' Texigryphaea belvederensis'' (Hill & Vaughan 1898) * '' Texigryphaea corrugata'' (Say, 1823) * '' Texigryphaea gibberosa'' (Cragin, 1893) * '' Texigryphaea graysonana'' (Stanton, 1947) * '' Texigryphaea hilli'' (Cragin, 1891) * '' Texigryphaea marcoui'' (Hill and Vaughan, 1898) * '' Texigryphaea mucronata'' (Gabb, 1869) * '' Texigryphaea navia'' (Hall, 1856) * '' Texigryphaea pitcheri'' (Morton, 1834) * '' Texigryphaea roemeri'' (Marcou, 1862) * '' Texigryphaea washitaensis'' (Hill and Vaughan, 1898)

References

Paleozoic life Gryphaeidae Prehistoric bivalve genera {{Bivalve-stub