There are many hundreds of species of fleas. Collectively, all of the species of fleas are categorized under the order name of Siphonaptera . The cat flea, Ctenocephalides felix , is the most commonly found flea in the US and infests cats, dogs, humans, and other mammalian and avian hosts. Fleas thrive in warm, moist environments and climates. The main flea food is blood from the host animal.
Host animals are many species - cats, dogs, humans, etc.
The total flea life cycle can range from a couple weeks to several months, depending on environmental conditions. The adult flea is very flat side to side. There are hair-like bristles on the flea body and legs to aid in their navigation through pet hair. Fleas have 3 pairs of legs, the hindmost pair designed for jumping. Fleas are well known for their jumping abilities .