Taxonomic revision of Leucascus Dendy, 1892 (Porifera: Calcarea) with revalidation of Ascoleucetta Dendy & Frederick, 1924 and description of three new species Author Cavalcanti, Fernanda F. Author Rapp, Hans Tore Author Klautau, Michelle text Zootaxa 2013 3619 3 275 314 journal article 10.11646/zootaxa.3619.3.3 2719c069-24fe-4cd6-967d-aea11f80e344 1175-5326 221852 92C07D63-F2F5-4898-A7FE-4937F4D5A043 Genus Leucascus Dendy, 1892 Diagnosis: Copiously branched and anastomosed choanocyte tubes covered by a continuous membrane. The exhalant aquiferous system is represented by a well-developed atrium delimited by a membrane with no choanoderm, supported by a specific skeleton of triactines and/or tetractines. The size of the spicules of the choanocyte tubes and of the cortical and atrial membranes is very similar. Apical actine of the tetractines ornamented with spines. Solenoid aquiferous system.