The Cyclocosmia spider is the oldest arachnid on Earth

The Cyclocosmia spider is the oldest arachnid on Earth
The Cyclocosmia spider is the oldest arachnid on Earth
Anonim

This is just an amazing creature - a spider print. The Cyclocosmia spider is considered the oldest arachnid on Earth. His ancestors appeared on the planet about 100 million years ago, at least the oldest find by paleontologists dates back to this period.

Cyclocosmia (Cyclocosmia truncata) has a peculiar truncated abdomen with an intricate pattern that closely resembles the ancient "seal". The abdomen of this spider ends abruptly with a hard, flat surface in the form of a disk, on which a very interesting pattern is located. It is somewhat reminiscent of one of the symbols of ancient civilizations, for example, the Maya.

The spider uses its disk as one of the methods of protection in cases of danger. They lead a sedentary lifestyle, so they do not move far from their burrows. During the threat, he crawls into his burrow head first and closes the entrance to the shelter with his hard disk.

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This method of defense is called phragmosis (pragmosis) - a method of defense when, when threatened, the animal hides in a hole and uses any part of its body as a barrier from the attacker.

The cyclocosmia spider belongs to the spiders of the trapdoor family (translated from English "trapdoor" means "trapdoor", "hatch"). All species of spiders of this family dig holes for themselves and make a cap, which is held by their paws from the inside. Trapdors are considered to be the oldest spiders on earth.

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They dig their burrows on steep slopes from sandy clay. Their depth can reach 7-15 centimeters. These spiders live in the southern United States: Florida, Louisiana and Alabama.

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They are not very large, the length of the body (together with the abdomen, but without legs), can reach 4-5 centimeters. Females are smaller, their length is 28 millimeters.

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They feed on insects. For a long time they can do without food (up to six months). During this time, cyclocosmia spiders crawl deep into the burrow and weave around themselves something very reminiscent of a cocoon. Has an aggressive character.

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The diameter of the "cork" in cyclocosmies can reach 16 mm, just enough to close the entrance to your favorite burrow with your own "rear". But the tricks of defense of hatch spiders do not end there - animals build their shelters on substrates that ideally match their "plug" in color, so predatory animals cannot see even a hypothetical burrow because the spider's abdomen merges perfectly with the environment.

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Such camouflage is an ideal system not only for defense, but also for attack. Signal threads stretch from the minks of Cyclocosmia, at night "the spider-hut turns to the forest in front", that is, it sits at the exit from the hole and keeps its paws on the web.

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As soon as a gape, sleepy coma or a sufficiently small vertebrate touches the spider's signaling, the spider instantly attacks its prey. If the target is reached, the victim is killed and dragged into the hole, the spider again takes its position of the "door" and sits down "booty to the top."

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Females of Cyclocosmia have a nasty and aggressive character (towards insects), especially when they are hungry, but nevertheless, the males manage to "pacify" their friends, although no one knows how. After fertilization, the female lays a cocoon and takes care of her babies - the captured prey is killed and chewed by the mother's chelicerae into a homogeneous mass, after which it is fed to the babies.

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