Pycnodonte
Pycnodonte is a genus of extinct oysters, fossil marine bivalve mollusks in the family Gryphaeidae, the foam oysters or honeycomb oysters. Shells of species in this genus are found around the world in fossil shell beds from the Valanginian to the Early Pleistocene. They are a commonly found fossil in Cretaceous shellbeds of the Navesink Formation in New Jersey.Species
Species within the genus Pycnodonte include:
- Pycnodonte amakusensis Tashiro 1978 †
- Pycnodonte belli †
- Pycnodonte brongniarti †
- Pycnodonte callifera †
- Pycnodonte convexa †
- Pycnodonte costei Coquand 1869 †
- Pycnodonte heermanni Conrad 1855 †
- Pycnodonte kansasense Bottjer †
- Pycnodonte mutabilis †
- Pycnodonte newberryi †
- Pycnodonte percrassa Conrad 1840 †
- Pycnodonte roanokensis †
- Pycnodonte squarrosa de Serres 1843 †
- Pycnodonte taniguchii †
- Pycnodonte trigonalis†
- Pycnodonte vesicularis †
- Pycnodonte vesiculosa Sowerby 1822 †
- Pycnodonte wardi †
Fossils of species within this genus have been found all over the world in sediments from Cretaceous to Quaternary.
The fossils generally exist in large layers or beds. In Utah, in the Capital Reef National Park area, this layer of fossils is up to ten feet thick, and is present in the lower Tununk section of the Mancos Shale Fraction, just above the Dakota Sandstone and below the Blue Gate Shale layer. In the Hanksville, Utah area, the Pycnodonte newberryi'' oyster bed is exposed over a large area. Studies are currently being conducted to determine whether there is more than one species in these beds.Gallery
