The molluscs compose the lairge phylum o invertebrate ainimals kent as the Mollusca. Aroond 85,000 extantspecies o molluscs are recognised. Molluscs are the lairgest marine phylum, comprisin aboot 23% o aw the named marine organisms. Numerous molluscs an aa live in freshwatter an terrestrial habitats. Thay are heichly diverse, nae juist in size an in anatomical structur, but an aa in behaviour and in habitat.