Cat flea

While grooming my cat, I noticed something in her hair, and I thought it was a little scab. It turned out it was a cat flea, Ctenocephalides felis. I held it between my fingers and thought how I would photograph it (live) without it jumping away. Fortunately, I found a little transparent plastic box which is part of the kids toys and put the flea on a white plate, and the box on top. The flea was very comfortable in this very narrow space, although it kicked its legs vigorously. I removed the clump of cat hair I had got it with and, voilà!  the flea was ready to photograph.

Cat flea photographic set up

Cat fleas actually infest a range of mammals, including dogs, racoons, sheep and many others. The adults live amongst the fur, feeding on blood. The eggs fall out of the cat and, those dropping on the animal usual sleeping places tend to be the ones developing successfully, and they are warmer and have the right humidity, as the larvae are very sensitive to cold temperatures and dry conditions. As for their food, they eat flea droppings, which are protein rich and contain only partially digested blood, so you could see this as a form of parental care, the parents providing food for the developing larvae in the form of droppings, which accumulate where the cat sleeps. 

More information
Rust, M. K., & Dryden, M. W. (1997). The biology, ecology, and management of the cat flea. Annual review of entomology, 42(1), 451-473. here.