Several people are now involved in genetically barcoding freshwater invertebrates of Australia. EPA Victoria has become involved to concentrate on the freshwater invertebrates of Victoria for biological monitoring purposes.

While this work has some way to progress for monitoring purposes, it is already producing information of wider interest. One aspect, large genetic variation within some species and genera, has big implications. Whilst for many taxonomic groups the gene sequences are confirming the morphological taxonomy, unexpected variation is occurring in others. Of the groups with larger genetic variation than expected, some are due to lack of existing morphological taxonomic research but others clearly represent variation that is not related to morphological variation. In some instances, a very large genetic distance can underlie very similar looking species, which may occur in close proximity.

Some examples of the groups with such variation are given from the Trichoptera, with barcodes for over 350 “species” now, to indicate the extent and significance of this problem. It seems that this type of variation exists particularly in taxonomic groups that are poor dispersers and have specific habitat requirements (e.g. Helicopsychidae, Antipodoeciidae) but this is not always the case (e.g. Leptoceridae: Notalina).

The implications of this variation are clearly important for ecological studies. Knowing which taxonomic groups include such large variation should be useful information to help select study species or understand population or trait variation. Taxonomic groups with such large variation within the Trichoptera will be detailed.