The Role of Sponges in Coralligenous Dynamics
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Fig. la-f. Section of a coralligenous ledge showing its structure mainly consisting of irregular layers of coralline algae. Under
higher magnification, the absence of any sponge boring activity in the upper side of the ledge (c) and a layer of boring chambers immediately under the lower surface (e) can be observed. The boring chambers (arrows) penetrate from the substrate into
the calcareous skeletons of Leptopsammia pruvoti (d) and Madracis pharensis (e). Large crevices of coralligenous structure are
occupied by endobiotic sponge species like Geodia cydonium (arrow) (f)