cephalaspid การใช้

• Ostracoderms existed in two major groups, the more primitive cephalaspids.
• The shells of the Volvatellidae and Oxynoidae somewhat resemble those of the Cephalaspid bubble snails.
• The cephalaspids were more advanced than the heterostracans in that they had lateral stabilizers for more control of their swimming.
• Most biologists regard this taxon as extinct, but the name is sometimes used in the classification of lampreys, because lampreys were once thought to be related to cephalaspids.
• At present, the oldest known " Undichna " were made by Cephalaspids, that only had presumptive motion scenarios, due to the mya, in an ancient riverbed environment.