Sertularia_perpusilla

Sertularia perpusilla is a very small colonial species of hydroids with polyps arranged symmetrically. It was found growing on the leaf of Posidonia oceanica at 7m depth. It is an endemic Mediterranean species and grows exclusively on Posidonia oceanica.

This specimen was identified and described in more detail (p. 189 & Fig. 5f) in the following paper published (2013) by Soto Àngel and Peña Cantero.