the core of the bellerophon gastropod of the carboniferous period & x28;carbon& x29;

ancient animal background bellerophon bivalve brown cambrian closeup detail epifaunal evolution exoskeleton extinct extinction feeders find formation fossil fossilized fossils gastropod geologic geological geology island isolated klint limestone macro marine mollusc mollusk natural paleontology period russia saaremaa sea seashell shell silurian specimen spiriferida spiriferidae sprier suspension white