I decided not to include all the sub-this and infra-that taxonomic levels on this site and stick to the ones covered in high school biology, because it makes the navigation much easier and it's sufficient for anglers' purposes.
For the rare cases in which some well-known taxon falls on a more obscure level (like crustaceans, damselflies, and dragonflies), I've appended or prepended it to the listed taxon with a hyphen and explained the details in the corresponding description. It's not the most graceful system but it works.
Jason Neuswanger, Ph.D.
Troutnut and salmonid ecologist