Figure 1. A in Calcareous sponges of the genera Clathrina and Guancha (Calcinea, Calcarea, Porifera) of Norway (north-east Atlantic) with the description of five new species

Figure 1. A, holotype of Clathrina corallicola sp. nov. Scale bar = 1 cm. B, spicules of C. corallicola. lte = large tetractines, ste = small tetractines and str = small triactines. Scale bar = 200 µm. C, SEM photo of spicules of C. corallicola. ap = apical actine of sagittal tetractine. Scale bar = 200 µm. D, distribution of spicules seen from the atrial side of the tube wall. Note that the apical actines of the tetractines are orientated towards the interior of the tube. Scale bar = 200 µm.