Neitheaとは 意味・読み方・使い方

Neithea is an extinct genus of bivalve mollusk that lived from the Early Jurassic to the early Paleocene with a worldwide distribution. Neithia sp. have inequivalve. That means, both valve is nonequivalent, the right valve is strongly concave and the left is flattened or concave. Sculpturing consist of alternating strong and weaker radiating ribs. Based on Fossil Invertebrates book, which written by Lehmann & Hillmer, Neithea occurred in Cretaceous