The Echinoid Directory

Family Echinidae Gray, 1825, p. 426

Diagnosis	Echinoida with: ambulacra typically trigeminate (quadrigeminate in one genus) with pore-pairs arranged either as rather vertical arcs or a dense adradial band; interambulacral plates with relatively sparse or reduced tuberculation, often highly granulose; buccal notches extremely feeble; paired lateral teeth on narrow tubular blade of globiferous pedicellariae.
Range	Miocene to Recent, Atlantic, Antarctic.
Remarks	Echinidae are primarily distinguished on their globiferous pedicellarial structure. Compared to Strongylocentrotidae they have mostly trigeminate ambulacral plating. Gray, J. E. 1825. An attempt to divide the Echinida, or sea eggs, into natural families. Annals of Philosophy 26, 423-431.