Taxonomy of calcareous sponges (Porifera, Calcarea) sampled on artificial substrates of a recreational marina in the Tropical Northeastern Brazilian coast Author Chagas, Cléslei Author Cavalcanti, Fernanda F. text Zootaxa 2017 2017-12-11 4363 2 203 224 journal article 31204 10.11646/zootaxa.4363.2.2 4fa4fe99-5cb7-4433-86f4-3c9d97b5b9fd 1175-5326 1098676 7B5AC657-18B1-4A90-9268-FFAD49E1B9D0 Genus Sycon Risso, 1826 “ Sycettidae with radial tubes partially or fully coalescent; distal cones are decorated by tufts of diactines. The inhalant canals are generally well defined between the radial tubes and are often closed at the distal end by a membrane that is perforated by ostia, devoid of a skeleton. There is no continuous cortex covering to the distal ends of the radial tubes. Skeleton of the atrium and of the tubes is composed of triactines, tetractines and/or pentactines” ( Rossi et al. 2006 ).