Acastoidea is a superfamily of trilobites. There are 23 species of Acastoidea, in 14 genera and 2 families. It includes groups like Acastidae and Calmoniidae.
Definition: overall repetitive or reflective pattern in the body of one individual of this taxon. eg: bilateral symmetry, rotational symmetry, radial symmetry
Definition: Component found in mineralized skeletal tissue, (a specialized form of biogenic tissue in which the extracellular matrix is mineralized, and which functions in mechanical and structural support.)