What does an engorged encephalitis tick look like? - briefly
An engorged encephalitis‑carrying tick appears markedly swollen, often the size of a small grape, with a rounded, distended body and a pale‑to‑reddish coloration. Its abdomen expands dramatically with blood, while the legs stay short and the mouthparts remain visible near the front.
What does an engorged encephalitis tick look like? - in detail
An engorged tick that can transmit tick‑borne encephalitis displays a markedly distended body. The anterior part, including the scutum, remains a hard, dark brown shield, while the posterior abdomen expands into a balloon‑like shape, often reaching several millimeters in diameter—up to 10 mm in some species. The expanded abdomen appears pale, sometimes reddish‑brown, and may be semi‑transparent, allowing the internal blood meal to be seen.
Key visual traits:
- Size: Length increases from 2–3 mm (unfed) to 5–10 mm (engorged); width expands proportionally.
- Color: Dark scutum contrasts with a lighter, swollen abdomen; overall hue may shift toward reddish or grayish tones as the blood is digested.
- Shape: Body becomes oval to spherical; legs remain attached and can be seen protruding from the sides.
- Mouthparts: The hypostome remains visible, often protruding slightly from the dorsal surface.
- Texture: The cuticle of the scutum stays rigid, while the abdomen becomes softer and more pliable.
The scutum does not enlarge; it covers the same proportion of the dorsal surface as in an unfed tick. Consequently, the engorged tick retains a distinct “shield” appearance over the head region, with the rest of the body visibly swollen. This morphology distinguishes it from other arthropods and from non‑engorged ticks.