How do sexual fleas bite? - briefly
Sexual fleas bite only to feed on blood, which supplies the nutrients required for reproduction. They puncture the host’s skin with their proboscis and inject saliva containing anticoagulants to facilitate blood intake.
How do sexual fleas bite? - in detail
Fleas locate a host through heat, carbon‑dioxide, and movement cues. Once contact is made, the insect anchors its hind legs and extends the piercing‑sucking apparatus located in the head. The mouthparts consist of a pair of slender stylets that act as a miniature drill. The inner stylet penetrates the epidermis, while the outer sheath guides it, creating a narrow channel through which blood is drawn.
During insertion, the flea injects saliva that contains anticoagulant proteins such as apyrase and anticoagulin. These compounds prevent clotting, maintain fluid flow, and reduce the host’s immediate pain response. Blood is then drawn up the pharyngeal canal by capillary action and stored in the midgut.
Female fleas require a blood meal to develop eggs; after engorgement they expand the abdomen and begin oviposition within 24–48 hours. Male fleas also possess functional mouthparts and may feed opportunistically, but their primary role is mating. After copulation, the female often seeks a new host to complete the blood‑feeding cycle, increasing the likelihood of multiple bites on the same individual.
The biting sequence can be summarized:
- Detection of host cues (heat, CO₂, movement).
- Jump onto host surface and secure position with hind legs.
- Extension of proboscis and penetration of skin using stylets.
- Injection of anticoagulant‑rich saliva.
- Ingestion of blood into the midgut.
- Detachment and relocation to a feeding site or new host.
The combination of mechanical piercing, biochemical saliva, and rapid blood uptake enables fleas to obtain the nutrients necessary for reproduction while minimizing detection by the host.