Fleas make up the taxonomical order ''Siphonaptera'' containing approximately 2500 species all of which are very similar in morphology. All are obligate blood feeders, which is apparent in the morphology of the mouthparts. Though they are all small, between 1 and 6mm, there is considerable sexual dimporphism, the females being larger than the males. The body of the flea is laterally flattened | Fleas make up the taxonomical order ''Siphonaptera'' containing approximately 2500 species all of which are very similar in morphology. All are obligate blood feeders, which is apparent in the morphology of the mouthparts. Though they are all small, between 1 and 6mm, there is considerable sexual dimporphism, the females being larger than the males. The body of the flea is laterally flattened |