Biting midge larva. Coloured scanning electron micrograph (SEM) of the head of a biting midge (family Ceratopogonidae) larva, showing its mouthparts (centre). Biting midges are small flies with painful bites. The larvae are found in damp areas, such as rotten wood, compost, mud, stream banks, tree holes and water-holding plants. The females suck blood from vertebrates and are major pests in late summer with horses and cattle as the normal hosts. They also potential transmitters of bluetongue disease, where a transmitted virus (Orbivirus sp.) causes fever, facial swellings and tongue cyanosis (blue colouring of the tongue) in ruminants. Magnification: x240, when printed 10 cm wide.