Cat Flea

Ctenocephalides felis — the cat flea — is the most cosmopolitan flea on Earth and the dominant flea species on cats, dogs, and many other domestic and wild mammals worldwide. Despite the common name, the species is not restricted to cats and is, in fact, the most common flea found on dogs (yes, the dominant flea on dogs is the CAT flea, not the much rarer dog flea Ctenocephalides canis). C. felis is a member of order Siphonaptera (the fleas, ~2,500 species worldwide) and shares the family-typical biology: laterally compressed wingless body, powerful spring-loaded jumping hind legs, piercing-sucking mouthparts adapted for vertebrate blood feeding, and a complex life cycle (egg, three larval instars, pupa, adult) that takes 2-4 weeks at room temperature. Cat fleas accelerate at approximately 100g during launch (Burrows 2009, Journal of Experimental Biology) — among the highest acceleration measurements in any animal — and routinely jump 100x their body length. The launch is powered by the resilin protein in the pleural arches (a rubber-like elastic material that stores energy across the legs and releases it explosively). Cat fleas are competent vectors of Bartonella henselae (the bacterium that causes cat-scratch disease in humans), Rickettsia felis (a typhus-related rickettsiosis), the dog tapeworm Dipylidium caninum (when accidentally ingested by humans, especially young children), and Yersinia pestis in some plague-endemic regions. The species is the reason flea-control products (fipronil, imidacloprid, selamectin, the modern isoxazolines) are a multi-billion-dollar global veterinary market.