What does a tick on an animal's skin look like?

What does a tick on an animal's skin look like? - briefly

A tick looks like a tiny, round, gray‑brown lump firmly attached to the animal’s skin, similar to a small, engorged bean. After feeding, its body swells, becoming smoother, balloon‑shaped, and often darker in color.

What does a tick on an animal's skin look like? - in detail

A tick attached to an animal’s integument appears as a small, rounded or oval structure that may be flat or dome‑shaped depending on its feeding stage. Unfed individuals measure 1–3 mm in length, possess a hardened dorsal shield (scutum) in hard species, and display a brown to reddish‑brown coloration. As blood intake progresses, the abdomen (idiosoma) expands dramatically, turning a pale gray‑white and increasing overall size to 5–10 mm or more. The front mouthparts (capitulum) project forward, often visible as a small, dark point near the skin surface. Six legs emerge from the anterior region, each bearing a short, claw‑like segment that grips the host.

Visible effects on the host include a localized, raised nodule where the tick inserts its hypostome. The surrounding skin may show mild erythema or a thin, translucent membrane that forms a feeding tube. In heavily engorged specimens, the tick’s body may protrude above the skin, creating a noticeable bulge. In some cases, the scutum remains visible as a darker patch on the dorsal surface, especially in male hard ticks that do not expand fully.

Key characteristics for identification:

  • Life stage:
    Larva – six legs, < 1 mm, translucent.
    Nymph – eight legs, 1–2 mm, light brown.
    Adult female – eight legs, engorged abdomen, up to 10 mm, pale.
    Adult male – eight legs, smaller, retains a visible scutum.

  • Tick family:
    • Hard ticks (Ixodidae) – rigid scutum, long feeding period.
    • Soft ticks (Argasidae) – leathery body, no scutum, shorter feeding bouts.

  • Attachment site: commonly ears, neck, groin, between toes, or under the tail where the skin folds create a protected niche.

The combination of size increase, color change, visible mouthparts, and the presence of a raised nodule provides a reliable visual profile of a feeding tick on an animal’s skin.