Tennessee

=**Tennessee**=

====**Description:** They have two-p//a//rt shells, with both being symmetrical, also having wedge-shaped shell and prominent ribs. It is in the class Bivalvia (known as bivalves) and are small invertebrate. It was one of the most common species during its time.====

**Pictures:**
====**Time Existed:** During the Cretaceous Period, around 73 million years ago. Lived at the floor of a shallow ocean that west Tennessee was covered by during the break up of the super continent Pangaea.====

====**Reason for it being the state fossil:**It is the state fossil because in 1996, a geological and geographical club at the University of Tennessee began a campaign to select the suitable fossil to represent the state of Tennessee. In 1998, //Pterotrigonia// //thoracica// was named the state fossil by the Tennessee legislature====