Group including the Anostraca (brine shrimps, fairy shrimps), Notostraca (shield shrimps), and Diplostraca (water fleas).
Barnacles are a diverse taxon including free-living and parasitic groups. Barnacles are sessile and most are hermaphroditic. Most are suspension feeders but many are parasites and some are predators. The exoskeleton usually secretes heavy calcareous plates which grow with the animal and are not moulted, although the rest of the exoskeleton is.
Class containing the Decapoda (crabs, crayfish, lobsters, shrimp), Peracarida (amphipods, isopods, mysids), Euphausiacea (krill), Phyllocarida (sea fleas), Stomatopoda (mantis shrimp), and others.
If your website is about keeping these animals as pets, submit to http://dmoz.org/Recreation/Pets/Fish_and_Aquaria/ .
Crustacean group in the class Maxillopoda.