LAUSR

Abstract Although early microscopists first described meiobenthic-sized animals from fresh water, it is widely acknowledged that studies of the ecology of freshwater meiofauna have taken longer to emerge as an independent discipline than those of their marine counterpart. The early literature on this freshwater fauna used terms relating to habitat rather than size. Perhaps this is partly because the term meiofauna originated early in the marine literature that lacked the cognizance of freshwater scientists. However, it is also undoubtedly due to the fact that, in the sea, animals in the meiofaunal and macrofaunal size ranges comprise recognisably separate ecological and evolutionary units with bimodal size spectra, whereas the freshwater size spectrum is more continuous and the division between the two categories is more arbitrary. This is due to the contrasting size-related life-histories of metazoans in the two realms.