Head louse, adult male (upper side), light micrograph. We can see the sucking mouth (the stylets are invaginated into the head, the sucked blood is visible), the two lateral ocelli and antennae, the thoracic and abdominal spiracles (perimetral holes to breathe), and the tactile hairs. It has highly specialized legs with a tibio-tarsal claw and a tibial spine, or spur. It cannot fly or jump but it moves quickly, climbing from hair to hair or from hair to fiber (towels, brushes, clothing, etc.) to infect a new host. The P. humanus capitis, order Phthiraptera, suborder Anoplura, is a wingless insect, an obligate hematophagic ectoparasite of humans which causes pediculosis capitis, more frequent in little girls, and spends its entire life on the human scalp. It is not a vector for any known diseases. Field of view size: 1.65 x 2.48 mm (0.065 x 0.098 in)