They are eyeless, legless and sparsely covered with hairs. The larval body is translucent white with a dark-colored gut that can be seen through the skin. Cocoons are sticky, attracting dirt and debris. This camouflage may prevent them from being seen. Their powerful hindlegs are well adapted for jumping and running through hair and feathers.
Females require a fresh blood meal in order to produce eggs.
The smooth eggs easily fall from the pet onto the carpet, bedding, or lawn. Eggs hatch within 2 days, and the developing larvae feed on dandruff, food particles, and skin flakes found on the floor around them. Adult flea fecal matter consists of relatively undigested blood. This dried blood also falls from the pet and serves as food for the newly hatched larvae. This stage lasts 5-15 days.