What does an unfed tick look like? - briefly
An unfed tick is a tiny, flattened arachnid, typically pale brown or gray, about the size of a grain of sand, with a smooth, oval body and clearly visible legs. Its mouthparts are short and not yet engorged.
What does an unfed tick look like? - in detail
An unfed tick presents a compact, oval body measuring roughly 2 mm in length for a nymph and up to 3 mm for an adult female. The dorsal surface is covered by a hard, shield‑like plate called the scutum, which is brown to reddish‑brown and bears a fine, raised pattern of grooves. The scutum’s outline is clearly defined, and in males it extends across the entire back, while in females it occupies only the anterior half, leaving the posterior abdomen exposed.
The ventral side is less sclerotized, appearing softer and lighter in color. Six slender legs protrude from the ventral region, each ending in a claw that can grasp hair or fur. The legs are pale, often ivory or light brown, and are noticeably longer than the body width, giving the tick a “spider‑like” silhouette when viewed from the side.
The front portion of the tick, the capitulum, houses the mouthparts. It consists of:
- A pair of chelicerae used to cut the host’s skin.
- A pair of palps that sense environmental cues.
- A hypostome, a barbed feeding tube that remains retracted when the tick is not attached.
In the unfed state, the hypostome is tucked beneath the capitulum and not visible externally. The eyes, if present, are tiny, dark spots located near the front of the scutum, but many species lack functional eyes altogether.
Key visual traits of an unfed tick:
- Small, rounded body, 2–3 mm (adult female) or 0.5 mm (larva).
- Dark brown to reddish dorsal shield with distinct grooves.
- Light-colored, elongated legs extending beyond the body edges.
- Concealed, needle‑like mouthparts beneath the front shield.
- Absence of visible blood expansion; abdomen remains flat and undeformed.
These characteristics distinguish a tick that has not yet taken a blood meal from its engorged counterpart, which appears markedly larger, rounded, and translucent due to the presence of blood.