What do house ticks look like? - briefly
House ticks are tiny, oval‑shaped arachnids, usually dark brown to reddish when unfed and measuring 2–5 mm. After feeding they swell dramatically, turning pale and balloon‑like, reaching up to about 10 mm in length.
What do house ticks look like? - in detail
House ticks are small arachnids ranging from 2 mm to 6 mm in length when unfed. Their bodies are divided into two main regions: the anterior capitulum, which houses the mouthparts, and the posterior idiosoma, which contains the legs and abdomen. The capitulum is typically dark brown to black and may appear slightly recessed, giving the tick a “shield‑shaped” silhouette.
Key visual traits:
- Coloration: Unengorged specimens exhibit a uniform brown, reddish‑brown, or grayish hue. After a blood meal, the abdomen expands dramatically and becomes pale or bluish‑white, contrasting with the darker dorsal shield.
- Shape: The dorsal shield (scutum) is oval or hexagonal, covering the entire back in males and only the anterior portion in females. The scutum’s surface is smooth, lacking distinct patterns or spots.
- Legs: Eight legs emerge from the idiosoma, each ending in tiny claws. The legs are relatively short, giving the tick a compact appearance. Leg segments are pale, often matching the body’s overall color.
- Eyes: Most house ticks lack visible eyes; instead, they rely on sensory pits (Haller’s organs) located on the first pair of legs.
- Mouthparts: The hypostome, a barbed feeding tube, protrudes from the front of the capitulum when the tick is attached to a host. In unfed ticks, it is retracted and not readily visible.
Life‑stage variations:
- Eggs: Microscopic, white, and oval, deposited in clusters on surfaces near hosts.
- Larvae (seed ticks): Approximately 0.5 mm, six‑legged, pale yellow, and difficult to see without magnification.
- Nymphs: Six‑mm, eight‑legged, similar in color to adults but smaller; the scutum is proportionally larger relative to the body.
- Adults: Fully developed eight‑legged form described above; females enlarge considerably after feeding, while males remain relatively constant in size.
Distinguishing house ticks from other indoor arthropods:
- Presence of a hard dorsal shield distinguishes them from soft‑bodied mites.
- Lack of wings and antennae separates them from insects such as beetles or flies.
- The characteristic “tick‑like” body outline—rounded anterior and broader posterior—differs from the flattened body of cockroaches.
Understanding these morphological details aids in accurate identification and effective control measures.