What does a tick look like under an animal's skin? - briefly
It appears as a tiny, swollen reddish‑brown nodule, often resembling a pinhead, with a dark central point where the mouthparts are anchored. Typically 1–3 mm in diameter, an engorged tick may become translucent and cause a noticeable bulge in the surrounding tissue.
What does a tick look like under an animal's skin? - in detail
A tick that has penetrated the host’s dermal layer presents a compact, oval body that appears flattened against the skin. The ventral side, which contacts the tissue, is covered by a smooth, pale‑gray or beige cuticle that often blends with surrounding tissue, making it difficult to discern without close inspection. The dorsal surface displays a darker, brownish to reddish hue, sometimes mottled, and may reveal the characteristic scutum—a hard shield that occupies most of the back in adult females and a smaller portion in males.
Key visual features include:
- Size progression: Engorged specimens can enlarge from 2–3 mm (unfed) to 10–15 mm (fully fed), swelling the abdomen dramatically while the scutum remains relatively unchanged.
- Leg visibility: Six legs remain visible around the perimeter; they are slender, pale, and may be partially obscured by the host’s fur or hair.
- Mouthparts: The hypostome, a barbed feeding tube, protrudes from the anterior margin, often appearing as a tiny, dark filament embedded in the tissue.
- Color shift: As blood fills the abdomen, the cuticle becomes more translucent, revealing a pinkish or reddish interior that may be visible through the skin.
- Surface texture: The cuticle is glossy when unfed, turning matte and slightly wrinkled after engorgement due to stretching.
Internally, the tick’s body consists of an anterior capitulum housing sensory organs and the feeding apparatus, and a posterior idiosoma that expands to store blood. The expansion produces a visible bulge that can be mistaken for a cyst or abscess if the tick is not recognized.
In practice, detection relies on observing a small, dome‑shaped protrusion surrounded by a ring of hair or fur, with the central area often slightly raised and of a contrasting color. The combination of size, coloration, leg arrangement, and the presence of a central mouthpart distinguishes the parasite from other subcutaneous lesions.