The Brittle Star Ophiocoma Wendtii

Scanning electron micrograph (SEM) of a part of the skeleton of a brittlestar Ophiocoma wendtii (Ophioroidea, Echinodermata). The entire structure (the mesh and the array of microlenses) is composed of a single calcite crystal used by the organism for mechanical and optical functions.

Joanna Aizenberg, David A. Muller, John L. Grazul, D. R. Hamann. Science 299, 1205 (2003).

Image courtesy: Dr. Joanna Aizenberg, Harvard.