Ticks
From IDWiki
Background
Microbiology
- Organised broadly into hard and soft ticks
- Hard ticks: typical tick with a dorsal plate (scutum; a hard shell on the back), and can easily see mouth parts
- Soft ticks: no distinct shell or dorsal plate; short mouths, often can't see mouth parts from above
- Tend to drop off the host after feeding
- "Questing" is when they hang out on tops of grass or plants, reaching out to grasp onto hosts that pass by
Identification
- Dorsal plate
- Can be ornate
- Festoons are specific decorations on the back; notches along the outside of the back
- Certain ticks (such as Ixodes scapularis) will have an anal groove
- Males and females look different
- Mature females feed and have large sacks behind the dorsal plate that fills up with blood upon feeding
- Nymphs are much harder to identify
- By species:
- Ornate black and white dorsal shield, with festoons, short mouth parts (unlike Amblyomma), and eyes: Dermacentor variabilis
- Black and white dorsal shield with some ornate markings, with festoons, long mouth parts, and eyes: Amblyomma americanum
- Female has a single white marking on the dorsal shield, hence lone star tick
- Plain dark dorsal shield, long mouth parts, no festoons, no eyes: Ixodes scapularis
- Also has an anal groove surrounding the anus in a U shape that opens posteriorly
- Soft tick lacking dorsal shield, with small mouth parts: most commonly Ornithodoros
- Rarely identified because they fall off after feeding