Lithonida

Minchinellidae is a family of calcareous sponges in the order Calcarea.^[1] It is the only family in the monotypic class Lithonida.

Description

Porosphaera globularis fossil from Cretaceous rocks in Germany

Calcaronea with reinforced skeleton consisting either of linked or cemented basal actines of tetractines, or of a rigid basal mass of calcite. Diapason spicules are generally present and the canal system is leuconoid.

References