菊石 是 菊石亞綱 （學名： ammonoidea）物種的通稱，是一類已 滅絕 的 頭足綱 軟體動物，具有螺旋形的 貝殼 和眾多 觸手。 作為非常好的 指準化石，菊石化石往往能連結起所在地層的 地質年代。 菊石. Ammonites were marine cephalopods resembling nautilus, characterised by their spiral shells and tentacles on their heads. Ammonites were shelled cephalopods that died out about 66 million years ago.
Joe Namath and Farrah Fawcett News Photo Getty Images
Discover beautiful, authentic ammonite fossils from around the world, perfect for collectors and enthusiasts alike. In other living cephalopods, e.g. This list of ammonites is a comprehensive listing of genera that are included in the subclass † ammonoidea, excluding.
Ammonites first appearing in the fossil record 240 million years ago, descending from straight shelled cephalopods.
Despite being creatures which occur so commonly as fossils that it seems like we should know everything about them, ammonites are creatures fraught with uncertainty for artists and. The last lineages disappeared 65 million years ago at the end of the cretaceous. Their chinese name derived from patterns of suture lines on their shells. Ammonites were marine animals belonging to the phylum mollusca and the class cephalopoda.
A variety of ammonite forms, from ernst haeckel 's 1904 kunstformen der natur. Fossils of them are found all around the world, sometimes in very large concentrations. Shop ammonites for sale on fossilera.com! Explore the captivating story of ammonite fossils, from their unique characteristics to their global distribution, and learn how these extinct creatures continue to captivate scientists and enthusiasts alike!
