Introduction

Welcome to the kingdom of the spiny underwater creatures

During our Professional practice, we studied two different species of sea urchins: Cidaris cidaris (Linnaeus, 1758) and Stylocidaris affinis (Philippi, 1845).

We obtained our samples from two different sites: the Ligurian sea and the Adriatic sea. The samples we examined were dry or conserved in ethanol. We performed an external observation using stereomicroscopes, optical microscopes and scanning electron microscope (SEM).

Stylocidaris affinis (Philippi, 1845)

Cidaris cidaris (Linnaeus, 1758)

We want to thank our fellow IMBRSea student Agathe Chomarat for these 3D models of the tests of our studied species.