FIGURE 28 in Calcareous sponges of the Western Indian Ocean and Red Sea

FIGURE 28. Ernstia arabica Voigt et al. 2017, ZMA Por. 13640, from the Gulf of Aqaba, a, habitus in situ (photo M. Wunsch), b–e, SEM images of sections of the cormus, b, overall section showing tightly anastomosed tubuli, c, cross section of tubuli showing apical actines of tetractines protruding in the tubar lumen, d, cross section of the surface region, e, detail of tubar lumen and protruding apical actines.