What do fleas and ticks look like? - briefly
Fleas are tiny, wingless insects about 1–3 mm long, laterally flattened, dark brown to reddish, with elongated hind legs for jumping. Ticks are small arachnids, 1–5 mm when unfed, round‑oval, reddish‑brown to dark brown, and possess a hard or soft dorsal shield depending on the species.
What do fleas and ticks look like? - in detail
Fleas are laterally compressed insects measuring 1–4 mm in length. Their bodies are deep‑brown to reddish‑black, with a hardened exoskeleton that gives a glossy appearance. The head is small and invisible from above; mouthparts form a piercing‑sucking proboscis adapted for blood feeding. Six short legs emerge from the thorax, each ending in a tiny claw that enables rapid jumping. Antennae are short, tucked beneath the head, and the abdomen expands after a blood meal, becoming visibly swollen.
Ticks are arachnids ranging from 1 mm (larval stage) to 15 mm (engorged adult). Their bodies consist of two main regions: the anterior capitulum, which holds the chelicerae and a barbed hypostome for attachment, and the posterior idiosoma, often covered by a hardened scutum in males and partially in females. Color varies with species and feeding status—unfed adults appear reddish‑brown to gray, while engorged females become pale grayish‑white and markedly enlarged. Eight legs are attached to the idiosoma; each leg bears sensory pits and claws for gripping hosts. The ventral surface may display a visible anal groove and spiracular plates.
Key visual distinctions:
- Body shape: fleas are laterally flattened; ticks are dorsoventrally rounded.
- Number of legs: fleas have six; ticks have eight.
- Size range: fleas remain under 4 mm; ticks can exceed 10 mm when engorged.
- Surface texture: fleas possess a smooth, glossy cuticle; ticks exhibit a textured scutum and visible leg segments.
- Mouthparts: fleas show a concealed proboscis; ticks display a prominent capitulum with a barbed hypostome.