What does an ixodid tick look like? - briefly
An ixodid tick is a hard‑bodied arachnid with a flattened, oval shape, a dark scutum covering the dorsal surface, and eight short legs. Its unfed body measures 2–5 mm and expands dramatically after feeding.
What does an ixodid tick look like? - in detail
Ixodid ticks are small arachnids with a compact, oval body that expands dramatically when they feed. The anterior region, called the capitulum, bears the mouthparts: a pair of chelicerae for cutting skin and a hypostome equipped with backward‑facing barbs that anchor the parasite during blood ingestion. The capitulum projects forward from the main body and is often visible as a short, beak‑like structure.
The dorsal surface features a hardened shield, the scutum, which covers the entire back in males and a portion of the back in females. In unfed specimens, the scutum is smooth, lightly sclerotized, and typically brown to reddish‑brown. Females possess a relatively soft, flexible cuticle beyond the scutum, allowing the abdomen to swell up to ten times its original size after engorgement, turning a pale, almost translucent hue.
Legs are eight in number, grouped in four pairs, each ending in a claw that assists in climbing vegetation. The legs are relatively long compared to the body, giving the tick a “spider‑like” silhouette. Leg segments are clearly demarcated, with the coxa attaching directly to the body and the tarsus bearing sensory organs.
Key visual differences between sexes and feeding states include:
- Males: fully scutated dorsal shield, smaller abdomen, dark brown coloration, no significant expansion after feeding.
- Females (unfed): partial scutum, lighter coloration, narrow abdomen.
- Females (engorged): enlarged, balloon‑like abdomen, pale gray‑white appearance, scutum remains visible as a small dark patch near the anterior.
Ventral view reveals the gnathosoma (mouthpart complex) extending forward beneath the body, and the anal opening positioned near the posterior margin. The overall morphology is adapted for attachment to host hair or fur, with the barbed hypostome and strong leg claws providing a secure grip.