Types of arachnids
Arachnids make up a large class of animals ( Arachnida ) belonging to edge of arthropods. Currently, more than 100 000 types of arachnids are known to spread widely throughout the planet, with the logical exception of Antarctica and the poles.
Next, we will see the main characteristics of these animals and we tell you which are the most common types of arachnids in the world .
General characteristics of arachnids
Like all arthropods, have eight legs and two pairs of appendages at mouth level. In some types of arachnids the two front legs suffered a Evolutionary modification by which they acquired sensory functions. In other species the appendices are so developed that they can become confused with legs.
The first pair of appendages are called 'chelicerae' and give name to the subfile of the quelicerados, to which the arachnids belong. Its main function is associated with food, but they are also powerful allies in its defense.
The appendices of the second pair are called 'pedipalps'. They are also essential for feeding arachnids, as they help capture prey. But its main functions are related to locomotion and reproduction.
The body of the arachnids is divided into two segments or tagmas: the cephalothora (or prosoma) and the abdomen ( or opisthosoma). Like all arachnids, they present an exoskeleton and its internal structure -where its vital organs lodge- that is composed of cartilaginous tissue.
The most characteristic feature that distinguishes arachnids from other arthropods is the absence of wings and antennae. In addition to its number of legs, in many cases.
The main types of arachnids on our planet
In the great class of arachnids There are 11 different orders, that comprise different species (some of them already extinct). These are the most common types of arachnids on our planet.
1. Araneae (Spiders)
Spiders make up the most diverse and abundant order in the class of arachnids ( Araneae ). Currently more than 40,000 spider species have been registered and described.
One of its most characteristic features is the presence of 'fangs' which, in reality, are its modified chelicerae. Through these 'fangs' poisonous spiders can introduce their toxins into the body of their victim.
Regarding their behavior and habits, highlights the amazing and recognized ability to build fabrics, woven by multiple silk threads. The so-called 'cobwebs' not only serve to trap their prey, but also act as shelters and can help them take advantage of the wind to move.
Despite its fame and its appearance, there are Very few spiders that pose a risk to humans . The vast majority of spiders have a shy and balanced nature, so they can hardly utter any attack on a person.