SEM images of the spicules of Grantia compressa (ZMA Por. 4159, from Roscoff, W coast of France). a club-shaped cortical diactine a1 detail of head b cortical triactine c tubar triactine d subatrial triactine, e. atrial tetractines, f. atrial triactine.

 
 
  Part of: Van Soest RWM, Hoeksema BW, Reimer JD, De Voogd NJ (2015) New records of the rare calcareous sponge Paragrantia waguensis Hôzawa, 1940. ZooKeys 546: 1-20. https://doi.org/10.3897/zookeys.546.6122