Mouthparts are long piercing and sucking tubular proboscis.
The labrum forms the proboscis sheath. It is like a long gutter or a half tube,
ending in a pair of white, pointed lobes, the labellae, which bears tactile hair.
The labrum bears a dorsal groove, which lodges all the other mouthparts
modified into 6 needle-shaped piercing stylets, all finer than hair, meant for
puncturing the skin of the host.
The epipharynx, which is an outgrowth from the roof of the mouth, becomes
completely fused with the labrum to form the labrum-epipharynx. This compound
structure makes a long, pointed, and stiff rod, which closes above the dorsal
groove of the labium.
The ventral surface of the labrum-epipharynx also bears a groove, which is
closed below by a long, pointed and flattened plate, like a double-edged sword,
called the hypopharynx. It is traversed by a minute median channel, the salivary
Mandibles and Maxillae
The paired mandibles and the first maxillae form long and needle-shaped
stylets, the former ending in tiny blades and the latter in saw-like blades. A pair
of long tactile maxillary pulps projects from the sides at the base of the proboscis.
Only the females can suck the blood, as they possess well-developed,
piercing mouthparts. In the males, the piercing organs are reduced, and the
mandibles are absent, but the sucking mouthparts are well-developed so that
they can suck up only plant juices.