Minchinellidae

Minchinellidae is a family of calcareous sponges, members of the class Calcarea.

[4] Thanks to their hypercalcified structure, minchinellids have a fossil record reaching as far back as the Jurassic Period.

They have a robust skeleton of tetractine (four-rayed) calcareous spicules.

These spicules may be linked by their basal actines or cemented together by calcite.

The skeleton is reinforced with layers of loose diapason (tuning fork-shaped) spicules.