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.
Comments
Post a Comment