Exogyra is an extinct
genus of
fossilmarineoysters in the family
Gryphaeidae, the foam oysters or honeycomb oysters.[1] These bivalves were cemented by the more cupped left valve. The right valve is flatter, and the beak is curved to one side. Exogyra lived on solid
substrates in warm seas[citation needed] during the
Jurassic and
Cretaceous periods.[2]
Taxonomy
The former
subgenusExogyra (Aetostreon) Bayle, 1878,[3] is sometimes considered a separate genus due to a lack of the fine set of parallel ribs (chomata) separated by pits on the inner surface of the valves (which is present in the nominate subgenus).[4]
Afghanistan, Chile, China, Eritrea, Ethiopia, France, Germany, India, Kenya, Poland, Portugal, Somalia, Spain, Tanzania, the United Kingdom, and Yemen.
Cretaceous
Afghanistan, Algeria, Argentina, Brazil, Bolivia, Canada (British Columbia), Bulgaria, Chile, Colombia (
Hiló Formation,
Tolima,
Macanal and
Chipaque Formations,
Eastern Ranges),[12][13] Cuba, the Czech Republic, Egypt, Ethiopia, France, Germany, Greenland, Hungary, India, Iran, Israel, Italy, Jordan, Lebanon, Libya, Madagascar, Mexico, Morocco, Mozambique, New Zealand, Nigeria, Oman, Pakistan, Peru, Poland, Portugal, Serbia and Montenegro, Slovakia, South Africa, Spain, Sweden, Switzerland, Tanzania, Trinidad and Tobago, Tunisia, Turkey, USSR, Ukraine, the United Kingdom, United States (Alabama, Arizona, Arkansas, California, Colorado, Delaware, Georgia, Maryland, Minnesota, Mississippi, Missouri, Montana, New Jersey, New Mexico, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Utah, Wyoming), Venezuela, and Yemen.
Acosta, Jorge E., and Carlos E. Ulloa. 2002. Mapa geológico del Departamento de Cundinamarca 1:250,000 - Memoria Explicativa, 1–108.
Colombian Geological Survey.