How many paws does a spider have: features of the movement of arachnids
Each animal has a special structure. There are amazing examples of what kind of "superpowers" representatives of the fauna have. Of interest are the legs of the spider, which perform several different functions.
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Representatives of arachnids
Spiders are often confused with insects. But in fact they are different classes. Arachnids are a large class that includes spiders. They, like insects, are representatives of the phylum Arthropoda.
This name itself speaks of the limbs and their segments - the parts of which they consist. Arachnids, unlike many arthropods, cannot fly. The number of legs also differs.
How many legs does a spider have
Regardless of the species, spiders always have 4 pairs of legs. They are neither more nor less. This is the difference between spiders and insects - they have only 3 pairs of walking legs. They perform different functions:
- beat an opponent;
- weave a web;
- build holes;
- as organs of touch;
- support the young
- retention of prey.
The structure of the legs of a spider
The legs, or as paws are often said, depending on the type of spider, have different lengths and thicknesses. But they have the same structure. The segments, they are also parts of the leg, consist of a number of parts:
- pelvic;
Spider structure.
- swivel;
- femoral part;
- knee part;
- shin;
- calcaneal segment;
- paw.
There is a claw segment that is not separated from the paw, so they are not separate.
The hairs that completely cover the legs act as an organ of touch.
The first and fourth pair of legs are the longest. They are walking. The third is the shortest.
Limb functions
The abdominal limbs are walking. They are long and allow spiders to move quickly, jump high with a spring. The movement of the spider from the side looks smooth.
This is possible due to the fact that pairs of legs have certain functions: the front ones are pulled up, and the rear ones are pushing. And from different sides there is movement in pairs, if the second and fourth pair are rearranged on the left, then the first and third are on the right.
Interestingly, with the loss of one or two limbs, spiders also move actively. But the loss of three legs is already a problem for arachnids.
Pedipalps and chelicerae
The entire body of a spider consists of two parts: the cephalothorax and the belly. Above the mouth opening are chelicerae that cover the fangs and hold prey, next to them are pedipalps. These processes are so long that they are confused with limbs.
hairs
There is hair along the entire length of the legs of the spider. Depending on the type, they may differ in structure, they are even, protruding and even curly. The heels of the fourth pair of legs have thickened setae in the form of a comb. They serve for combing the web.
How long are the legs of a spider
The length varies from minimum to maximum depending on living conditions and lifestyle.
The haymaker.
Harvestmen, which are often attributed to spiders, are actually false spiders, have very long legs and a gray body.
Several record holders:
- Brazilian wandering spider - more than 15 cm;
- Baboon - more than 10 cm;
- Tegenaria - more than 6 cm.
It happens that even in the same species of spider, under different living conditions, the size and length of the legs vary.
Conclusion
The spider has eight legs. They are responsible for a number of important functions besides locomotion. This indicator is unshakable and distinguishes spiders from other arthropods and insects.
