Search results
Results from the WOW.Com Content Network
Tuarangia is a Cambrian shelly fossil interpreted as an early bivalve, [1] though alternative classifications have been proposed and its systematic position remains controversial. [2] It is the only genus in the extinct family Tuarangiidae [ 3 ] and order Tuarangiida . [ 1 ]
Neithea is an extinct genus of bivalve molluscs that lived from the Early Jurassic to the early Paleocene, with a worldwide distribution. [1] Neithia sp. are inequivalve. That means that the two valves are not the same shape, the right valve being strongly concave and the left valve being flattened or concave.
Bivalve fossils can be formed when the sediment in which the shells are buried hardens into rock. Often, the impression made by the valves remains as the fossil rather than the valves. During the Early Ordovician, a great increase in the diversity of bivalve species occurred, and the dysodont, heterodont, and taxodont dentitions evolved.
Of Campanian age, this genus is widespread as a fossil in Cameroon, France, Poland, Austria, Germany and the United States. Fossils up to the Neogene have been found in Belgium , the United Kingdom , and Venezuela ( Pliocene Mare and Playa Grande Formations ) and Miocene Bulgaria , Chile , Colombia , Cyprus , Germany, India , Japan , Malta ...
Anadara is a genus of saltwater bivalves, ark clams, in the family Arcidae. It is also called Scapharca. [1] This genus is known in the fossil record from the Cretaceous period to the Quaternary period (age range: 140.2 to 0.0 million years ago). These fossils have been found all over the world. [2]
Entobia in a bivalve shell, Florida.. Entobia is a trace fossil in a hard substrate (typically a shell, rock or hardground made of calcium carbonate) formed by sponges as a branching network of galleries, often with regular enlargements termed chambers.
This genus is known in the fossil record from the Carboniferous period to the Eocene period (from about 313.8 to 37.2 million years ago). Fossils of species within this genus have been found in marine sediments all over the world.
Requienia is an extinct genus of fossil saltwater clam, a marine bivalve molluscs in the order Hippuritida, family Requieniidae. These rudists lived in the Cretaceous period, from the Valanginian age (136.4–140.2) to the Campanian age (70.6–83.5 mya). They were stationary intermediate-level suspension feeders.