Sand Dollar Anatomy Diagram - Marine Biology Educational Illustration #1711 (License: Personal Use)

This minimalist line drawing depicts the dorsal (upper) surface of a sand dollar, emphasizing its characteristic five-rayed (pentaradial) symmetry formed by petal-like ambulacral areas. The central disc represents the madreporite, while the irregular outer edge outlines the test-the rigid, calcareous shell of this marine echinoderm. The style is educational, suitable for textbooks, field guides, or interactive marine biology resources.

Used in educational websites, K-12 science curricula, museum exhibits, and nature apps to teach echinoderm morphology; matches user intent for visual identification, anatomy study, or printable classroom material.