Tags: Crustacean.
Tantulocarida is a highly specialised group of parasitic crustaceans that consists of about 33 species treated as a subclass of the class Maxillopoda (copepods and barnacles). They are typically ectoparasites that infest copepods isopods tanaids amphipods and ostracods. Members of this subclass are minute – less than 0.3 millimetres (0.012 in) in length and have a dramatic reduction in body form compared to other crustaceans with an unsegmented sac-like thorax and a much reduced abdomen.