What does a tick look like in a picture? - briefly
A tick appears as a small, oval‑shaped arachnid, typically dark brown to reddish, with a flat dorsal surface and six visible legs on the anterior half. The unfed body measures about 2–5 mm, expanding to several millimeters after engorgement.
What does a tick look like in a picture? - in detail
A tick appears as a small, oval‑shaped arachnid, typically ranging from 2 mm to 6 mm in length when unfed. The dorsal surface is covered by a hard plate called the scutum, which is usually brown to reddish‑brown and may display a pattern of lighter or darker spots. The ventral side shows a soft, pale membrane that expands after feeding. The body is divided into two main sections: the anterior capitulum, which houses the mouthparts, and the posterior idiosoma containing the legs and internal organs.
Key visual elements include:
- Capitulum with a pair of short, forward‑projecting chelicerae and a hypostome that appears as a bar‑shaped structure;
- Four pairs of legs, each jointed and relatively short, giving the tick a compact appearance;
- Scutum, often smooth but sometimes bearing fine striations or a mottled pattern;
- Eyes positioned near the anterior margin of the scutum, appearing as tiny dark dots;
- Silky, unsegmented body surface that may exhibit a glossy sheen in well‑lit photographs.
Life‑stage differences are evident in size and scutum development. Larvae (seed ticks) are translucent, measuring about 0.5 mm, with an unpigmented scutum. Nymphs are larger (≈ 2 mm), showing a partially pigmented scutum and more distinct leg segmentation. Adult females enlarge dramatically after a blood meal, expanding to 10 mm or more, with a markedly engorged abdomen that appears balloon‑like and lighter in color. Males retain a smaller, less engorged abdomen and a fully visible scutum.
Distinguishing characteristics from similar arthropods: the presence of a capitulum with a hypostome, the arrangement of four leg pairs, and the characteristic scutum differentiate ticks from insects, which possess three pairs of legs and distinct wing structures. The combination of a compact, oval silhouette, a dorsal shield, and specialized mouthparts provides a reliable visual signature for identification in photographs.