Genomic resources and reverse genetics methods presently available for representative model species of non-bilaterian Metazoa. Available methods for each group plotted on a cladogram (tree after [2, 17]). While EST and/or genomic data are available for many representatives of each clade, functional (transgenic and silencing) techniques have only been adapted to a few non-bilaterian groups. The present study provides the first RNAi silencing protocols for a part of the Porifera, i.e. the two cultivatable Demospongiae G4 species Ephydatia muelleri and Tethya wilhelma (asterisk). There are no species currently maintainable in laboratory cultures among the demosponge clades G1 to G3, which would be an important prerequisite for future extensive RNAi studies.