Coralline algae preparation for scanning electron microscopy and optical microscopy

Coralline algae (CA) are habitat builders with a worldwide distribution in benthic ecosystems from the intertidal to the lower boundaries of the euphotic zone, fulfilling a paramount role as substrata for other organisms, and promoting biodiversity. Here, we describe the protocols for sample preparation for scanning electron microscopy (SEM) and thin sections of optical microscopy (OM), which allow acquiring the anatomical features relevant for CA taxonomic identification. The same procedures can be also useful in energy dispersive spectrometry (SEM–EDS) analyses.