Tick Ixodes ricinus
Ticks usually are parasites living mainly on birds and mammals. Below you see pictures of tick nymphs. To the left a freshly hatched nymph, for like all mites the first instar has 6 legs only. To the right a later instar, which is complete and equipped with 8 legs. The tick is a small animal indeed, but that does not mean it isn't dangerous. On the contrary, ticks can be very dangerous indeed! They suck blood from mammals, including humans. Normally they bite you and hang on to you for one or two weeks, before letting go. But in the mean time they can give you some serious diseases. In Holland and Belgium the only disease they are spreading at the moment is Lyme's disease. This is a very severe illness, unless treated early with heavy medication. So when you detect a tick somewhere on your body check the spot regularly for weeks. When it's getting red, and white and red ringlets appear, do see your doctor immediately. In Central and Eastern Europe Ticks can transmit more diseases, all quite serious.
The smallest nymphs, those just hatched, have three pairs of legs only. Six legged mites are often called larvae instead of nymphs. In the bottom picture but one is such a larva. Only after they have bitten their first victim, they cast their skin for the very first time and with that the fourth pair of legs appears and from that moment on they are called nymphs. The black animals are males, the red ones females. Once adult, the male doesn't bite anymore. Being a larva or nymph the male sucks blood just like the female does, but once it is adult it stops eating alltogether. Like a female it waits on a stem for a hot blooded animal to pass by and just like the female it crawls on this animal when it is brushing against the plant. But instead of sucking blood it searches for females to mate. Given the chance, ants will not hesitate taking a tick back to the nest. Ticks heve no ways to defend themselves against ants. Their mouth is too specialized and they move extremely slowly. So they are an easy prey. In the bottom picture an ant attacking a tick.
Even though ticks have four pairs of legs, they only use the last three pairs to walk about. As they do not have antennae, the first pair of legs is used as such. They are packed with sensitive nerves and these are used to find victims, mates etc. That is why in some pictures the front legs are held up.
