FIGURE 3 in A new Clathria (Demospongiae, Microcionidae) from Peru occurring on rocky substrates as well as epibiontic on Eucidaris thouarsii sea urchins

FIGURE 3. Transversal fracture of a spine of the sea urchin Eucidaris thouarsii (SEM) showing the structure of the skeleton of Clathria (Microciona) aculeofila sp. nov. MNRJ 13317. 1 = basal layer of spongin, 2 = echinated paucispicular fibres.Published as part of Aguirre, Karem, Hooker, Yuri, Willenz, Philippe & Hajdu, Eduardo, 2011, A new Clathria (Demospongiae, Microcionidae) from Peru occurring on rocky substrates as well as epibiontic on Eucidaris thouarsii sea urchins, pp. 41-54 in Zootaxa 3085 on page 49, DOI: 10.5281/zenodo.20553