Mites and Ticks (Order Acarina)
What do mites and ticks look like?
An Australian Paralysis tick. Electron micrograph: S Lindsay © Australian Museum.
Illustration: A Howells © Australian Museum.
- Size:
- Most are microscopic but some reach a size of almost 10 mm in length.
- Body:
- No constriction between the cephalothorax (front portion containing head) and the abdomen. Though the two regions maybe distinctive.
- Abdomen without segments, highly variable in shape and appear hard.
- Antennae:
- Absent.
- Eyes:
- Up to four simple eyes.
- Mouthparts:
- Variable depending on their food choice. Generally they have mouthparts for ripping, cutting, mushing, chomping, clinging, piercing or sucking.
- Wings:
- Absent.
- Limbs:
- Eight legs but young mites often have only six.
- Pedipalps (appendages between first legs and mouthparts) are leg-like or modified for gripping prey.
- Abdomen tip:
- Cerci (tails) absent.
Where are mites and ticks found?
- Ticks and some mites are associated with animals, including humans. They maybe found on the surface of animals or internally in nasal passages or lung chambers.
- Mites can be found anywhere on land but are prolific in the soil, in leaf litter and on plants.
- Mites are found in most freshwater and marine environments including the depths of the ocean.
- Mites are found in houses, especially in carpets.
What do mites and ticks do?
- They are free-living or parasitic.
- They can be solitary or they can group together in large numbers to feed.
- When disturbed mites run from danger, while ticks clamp onto the animal they are on.
- As a group they have adapted to feed on anything including small invertebrates, bacteria, fungi, plants, animal bodily fluids, decaying organisms and waste products.
- Predatory mites hunt or ambush prey. They are known to kill prey by impaling, jabbing, entangling with silk or poisoning them.
- Many move from one region (or host) to the next by clinging to larger animals.
- They are active during the day or night.
What looks similar?
- Ticks and mites are not generally confused with other invertebrates, but their young are occasionally mistaken for insects as they have only six legs.
