The All Phyla Family Level  TCE will consist of image sets (3-5 images) for 40 taxa selected from an image database in a stratified random manner representing the relative frequency of occurrence of the groups representing families of insect adults (aquatic forms only) and larvae; orders of benthic insect pupae; families of Mollusca; and higher taxonomic levels of other invertebrate groups (Oligochaeta, Hirudinea, Crustacea, and Arachnida) found in North American lakes and streams. For a complete list of families and other groups in the test see this link.  While every attempt is made to keep these current they should be considered as a guide.