Content
Mouthparts are long piercing and sucking tubular proboscis.
Labrum
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.
Labium-Epipharynx
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.
Hypopharynx
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
duct.
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.
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