![]() ![]() Sponges feed by filtering bacteria and organic particles out of the water. ![]() Most Australian species are thought to reproduce by asexual reproduction. If sexual reproduction is occurring, parenchymella larvae are produced and disperse before developing into the mature sponge. A vegetative growth phase is followed by gemmulation (asexual reproduction) or sexual reproduction, cryptobiosis (resting phase), the hatching of gemmules, and finally regeneration. Two families (Spongillidae and Metaniidae) consisting of 11 genera and 27 species are reported from Australia.Ī generalised life cycle of a freshwater sponge can consist of five stages that can be repeated several times a year. There are approximately 220 species of freshwater sponge from 45 genera in six families worldwide. The freshwater sponges have colonised a wide range of environments and substrates at all latitudes. The oldest fossil evidence of freshwater sponges is from the Cretaceous. Gremmules are internal buds which form through asexual reproduction and are resistant to harsh conditions, allowing the sponge to resist hostile environments in a resting phase and re-establish when conditions are more suitable. The key character that is thought to have enabled the diversification of sponges into inland waters is the presence of gremmules. Freshwater sponges show a high diversity of colours, sizes, body shapes and textures and are found worldwide. The phylum Porifera contains predominantly marine sponges it is only in the suborder Spongillina within the order Haplosclerida that the freshwater species are found. Order Haplosclerida, Suborder Spongillina
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