The Echinoid Directory

 Scutellidea with:

• internal buttressing in the form of stellate clusters with well-defined adradial bars and V-shaped interradial channels;
• four gonopores;
• petals well-developed, nearly closed distally; with accessory pores in perradial zone;
• basicoronal circlet with interambulacral elements pointed and projecting; interaambulacral zones disjunct with one pair of ambulacral plates separating basicoronal plate from succeeding interambulacral plates;
• Broad, open posterior notch;
• Periproct oral, opening between second pair of interambulacral plates.

  Miocene of North and South America.

Durham (1955) included only the genus Abertella in this family but Mooi et al. (2000) expanded it to include a second genus, Karlaster, which they treat as junior synonym of Abertella.

Durham, J. W. (1955) Classification of clypeasteroid echinoids. California University Publications in Geological Sciences 31, 73-198.

R. Mooi, S. Martinez & S. G. Parma 2000. Phylogenetic systematics of Tertiary monophorasterid sand dollars (Clypeasteroida: Echinoida) from South America. Journal of Paleontology 74, 263-281.