Fleas are a type of wingless insect which feed of the blood of their hosts using a tube which pieres the skin. They are classified in the order “Siphonaptera” (Siphon – tube, a-ptera – wingless) Flea species include:Species of flea are often identified by the presence or absence of combs made of spines found in two places on the head.Scientific classification of the Dog FleaCtenocephalides canis