Mouthparts
Mosquitoes are solenophages, meaning they feed directly from blood vessels by penetrating their mouthparts through the vertebrates skin (Lavoipierre 1967). Their long proboscis allows them to probe deep in search of capillaries (Gullan & Cranston 2010).
The mouthparts that form the proboscis are (see diagram at right): · Labium (lb) – a protective sheath surrounding the functional mouthparts (the stylet bundle) with two sensory labella (singular: labellum) on the end. The labella contain receptors for stimuli that can indicate suitable feeding sites. · Two mandibles (md) – sharply pointed appendages used to rupture the skin, creating an entry passage. · Two maxillae (mx) – have a serrate-edge, and are the main penetrative appendages. The teeth are used as anchors in the tissues. · Labrum (lr) – the food channel. · Hypopharynx (hp) – the salivary channel. (Becker et al. 2003; Gullan & Cranston 2010) |
When a female feeds, she will often probe her host’s skin with the labella, searching for a capillary (Becker et al. 2003). Once she locates a suitable site, she then punctures the skin, and begins feeding. Through this process, only the stylet bundle enters the host. The labium is bent backwards (or bowed), remaining outside the wound (Gullan & Cranston 2010). Saliva (containing anticoagulants) is also injected into the wound while she feeds, preventing the blood from thickening or clotting (Resh & Carde 2009). It can also cause the site to become itchy as it stimulates the immune system, causing an inflammatory response (Becker et al. 2003).