The Tiny Tick-ler

What am I looking at?

This is an image of the head (1) and mouth (2) of a tick (Ixodida). In this image you can see the hypostome (3), part of the mouth that contains backward facing spikes that make it hard to pull the tick off once it is attached. There are also two mobile structures on the outside of the mouth called palps that move out of the way before a tick takes a bite (4).

Biology in the Background

Ticks are small parasitic arachnids (the same class as spiders) that feed on the blood of other animals, including humans. They are so small that the amount of blood that they take for a meal does not harm the animals they feed on. However, there are multiple diseases that ticks can spread to other animals while feeding, including Lyme disease, Rocky Mountain spotted fever, and Tularemia. Because of this, they have earned a bad reputation among those who spend significant time outdoors.

Their specialized mouthparts are the secret to their success as a parasite. The outermost structures of the mouthpart help a tick find a host, using sensory cues such as odor, body heat, moisture, and vibration. Ticks rest on the tips of grasses, leaves, and shrubs waiting for their next meal. When an animal passes close by, the tick grabs on, finds a patch of skin, and uses their mouthparts to pierce the skin and feed.

The tick mouthparts can measure up to 1.5 millimeters long, or roughly 17 times larger than the width of a human hair.  

Technique

This image was created using scanning electron microscopy.