How does a tick look in close-up? - briefly
Under magnification, a tick appears as a tiny, oval arachnid with a hardened dorsal shield (scutum) covering the back and six-legged front segment visible. Its mouthparts form a protruding, barbed hypostome, while the body exhibits segmented legs and a smooth, dark exoskeleton.
How does a tick look in close-up? - in detail
A tick observed at high magnification measures approximately 2–5 mm in length when unfed, expanding to 10 mm or more after engorgement. The body consists of two distinct regions: the anterior capitulum, housing the chelicerae and hypostome, and the posterior idiosoma, covered by a hardened scutum in males and partially in females.
The capitulum appears as a compact, dark‑colored structure with four elongated pedipalps and a pair of short, hook‑like chelicerae. The hypostome, bearing rows of backward‑pointing teeth, protrudes from the ventral side of the capitulum and facilitates attachment to host tissue.
The idiosoma displays a smooth, oval dorsal surface. In engorged specimens, the cuticle stretches, revealing a semi‑transparent, blood‑filled interior. The ventral side contains the gnathosoma and a series of spiracular plates for respiration.
Key anatomical features observable in close view:
- Scutum: a sclerotized shield, dark brown to black, covering the anterior dorsum.
- Legs: eight slender appendages, each ending in a claw; the tarsus exhibits fine sensory setae.
- Eyes: a pair of simple eyes (ocelli) located on the lateral margins of the scutum in some species.
- Spiracles: small openings on the posterior dorsum, surrounded by a ring of short setae.
Under magnification, the surface texture appears glossy, with fine punctate markings on the scutum and minute hairs covering the legs and ventral plates. The overall morphology reflects adaptations for parasitism, including a robust mouthpart assembly and expandable body wall.