Kingdom: Animalia (Latin root: animalis- "animal, living creature") (Memidex 2012)
-Some characteristics of this kingdom include multicellularity, heterotrophic, typically reproduce sexually, cells do not contain cell walls, are capable of motion in some stage of their lives, and are able to use nerve cells, muscle or contractile tissue, or both to respond to external stimuli. (University of Arizona 2004)

Phylum: Arthropoda (Latin/Greek roots: arthro- "joint" & poda- "foot") (Memidex 2012)
-Some characteristics of this phylum include a segmented body, segmented appendages, bilateral symmetry, chitnous exoskeleton, tubular alimentary canal with a mouth and anus, open circulatory system, a coelom, nervous system, striated muscles in skeletal system, and respiration through gills, tracheae, or spiracle (University of Minnesota 2009)

Class: Insecta (Latin/Greek root: insectum- "cut up/segmented") (Memidex 2012)
-Some characteristics of this class include a body divided into three parts/tagmata (head, thorax, and abdomen), a pair of compound eyes, usually three ocelli located on the head, a pair of antennae located on the head, mouthparts consisting of a labrum, two mandibles, two maxillae, a labium and a "tongue-like" hypopharynx, two pairs of wings that are outgrowths of the body wall, and three pairs of legs. (Myers 2001)

Order: Siphonaptera (Latin/Greek roots: siphon- "hollow tube" & apteros- "wingless") (Memdiex 2012)
-Some characteristics of this order are that they are parasites that live on other creatures without killing them, their bodies are hard and are flattened from side to side, are dark colored, 1-9 mm in length, wingless, and great jumpers (Amateur Entomologists' Society 2012)

Family Pulicidae
-Also referred to as the family of the "common flea", characteristics include being 1-2.5 mm in length, having one row of bristles on each abdominal segment, and most attach to humans and/or domestic animals. (McLeod 2005)

Genus: Ctenocephalides
-This genus includes both the species that commonly infect dogs and cats. (Richards and Davies 1977)

Species: Ctenocephalides felis (Latin root: felis- "cat") (McLeod and Moisset 2009)