Mosquito pupae and larvae. Light microscope footage of mosquito pupae (family Culicidae) at the surface of water, with mosquito larva feeding and swimming in the foreground. Mosquito larvae are aquatic and breathe through spiracles located on their abdomen, or through a siphon (breathing tube) on the end of the abdomen as seen here. They feed by wafting algae and other detritus suspended in the water into their mouths, using the beating hairs of their mouth brushes to create a current. After one to two weeks the larvae pupate. Each pupa has a fused head and thorax (cephalothorax) and segmented abdomen. After a few days, depending on the water temperature, the pupae rise to the surface of the water, their cephalothoraxes split and the adults emerge.