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Venus (bivalve)
''Venus'' is a genus of small to large saltwater clams in the family Veneridae, which is sometimes known as the Venus clams and their relatives. These are marine bivalve molluscs. Etymology The genus ''Venus'' is named after Venus (mythology), Venus, the Roman goddess of love and sexuality. Taxonomy However, some bivalves are still called Venus clams because they used to be in the genus ''Venus'', though they are now placed in other genera: these include the species within the genus ''Mercenaria'', and ''Pitar dione'', the Venus shell described in sexual terms by Linnaeus. Fossil records The genus is known from the Cretaceous to the Holocene, recent periods (age range: from 136.4 Mya to now). Fossils shells have been found all over the world. About 20 extinct species are known. The family Veneridae The family Veneridae contains over 400 known species, many of which are attractive and popular with shell-collectors. The shells of venerids vary in shape, and include shells that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
