Anatomy Pteraspidiformes



rhinopteraspis fossil


a pteraspidiform heterostracan has cephalothorax enclosed in armor, formed several plates, including dorsal, ventral, rostral, pineal plates, dorsal spine derived scale, , large, scale-covered tail. many genera benthic, others apparently active swimming nekton. delicate, finger-like components of anterior end of ventral plate forming edges of mouth suggest pteraspidiform heterostracans filter-feeders selectively filtered specific sized plankton water column.








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