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Texigryphaea
''Texigryphaea'' is an extinct genus of oyster belonging to the order Ostreida and family Gryphaeidae. It dates to the Albian to Cenomanian Ages of the Cretaceous period 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 oysters that were often the dominant species in late Albian biomes of the Western Interior Seaway. Some limestone beds of the Muleros Formation near El Paso, Texas, 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 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 belv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Texigryphaea Belvederensis
''Texigryphaea'' is an extinct genus of oyster belonging to the order Ostreida and family Gryphaeidae. It dates to the Albian to Cenomanian Ages of the Cretaceous period 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 oysters that were often the dominant species in late Albian biomes of the Western Interior Seaway. Some limestone beds of the Muleros Formation near El Paso, Texas, 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 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 b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muleros Formation
The Muleros Formation is a geologic formation in New Mexico, which is particularly well exposed at Cerro de Cristo Rey near El Paso, Texas. It preserves fossils dating back to the early Cretaceous period. Descriptiom The formation consists of highly fossiliferous nodular argillaceous (clay-rich) limestone at its base and in its upper portion, with shale dominating the middle section and interbedding with the limestone towards the top of the formation. Total thickness is . The formation conformably overlies the Smeltertown Formation and grades into the overlying Mesilla Valley Formation. The formation is interpreted as an outer shelf formation that later experienced shallowing and deposition of limestone in an inner shelf environment subject to storm influence, then deepened again to deposit shale with some storm layers. Fossils The formation contains at least 20 genera and 23 species of fossils. These include the molluscs ''Lima wacoensis'' Roemer, ''Lima mexicana'' Bose, '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |