Black Thickhead - Eresus collari Rossi
The most beautiful spider on the planet — this is what most arachnologists believe. And it really is true! By the way, this is a rare, endangered species. The thickhead has eight eyes arranged in three rows. Males have an orange-red abdomen on top, with four round black spots and usually two small black dots. Females have a completely velvety black abdomen. The legs are thick and hairy; the front two pairs of legs in males are black with white rings, while the back pairs are orange.
The spider inhabits burrows and under stones, preferring hilly areas covered with grass and small bushes. It digs a shallow vertical burrow, lining it with silk, part of which protrudes above the ground like a roof. The female and young spiderlings hibernate in the burrow, going into a state of dormancy.
It primarily feeds on beetles. The Eresus lines its burrow with silk so that it forms a tube. Nearby, on the ground or low grass, the thickhead constructs a hunting net in the form of a canopy. There are no sticky threads in it, but it is made of a special ultra-thin chaotic web that is easy to get tangled in. The thickhead's net is so strong that it can hold even large beetles - such as darkling beetles and dung beetles. It is connected to the silk tube by several signal threads, the vibrations of which inform the spider that a prey has been caught in the trap. It quickly jumps out, grabs the prey, and paralyzes it with venom. The remains of the food are either thrown out of the burrow or stored in a special compartment.
Most of the thickhead's life is spent in their underground shelters. Only young spiders lead a wandering lifestyle, still searching for a place to live, as well as males wandering in search of mature females. They set out in spring, changing their black coloration after wintering for their bright attire.
After prolonged searching, the male finally finds a suitable partner and begins courting at the entrance to the burrow. This courtship is quite peculiar and resembles a whimsical dance that can last several hours.
The methods of seduction vary: they can include courtship dances and the offering of a "gift." Additionally, all spiders emit pheromones that can "daze" the female.
The spider circles around its lady love, sometimes feeling her with its front legs. Finally, it releases a whitish fluid, causing the female to enter a state of catalepsy for about 40 minutes, allowing the male to safely mate with her. After this, the male remains to live in the burrow with his chosen one.
About a month later, the female creates a silk cocoon measuring 9 x 3 mm and lays her eggs inside. She shows tender care for her offspring: she finds the most comfortable place for the cocoon and brings it out to warm in the sun. After 10-20 days, the spiderlings emerge from the eggs. Before reaching sexual maturity, females undergo 10 molts, while males undergo 5. After the first molt, the young spiders begin to feed on their mother's hemolymph, which is necessary for their successful development. By the end of summer, after three molts, they start to crawl out of their native burrow to find a place for wintering. Meanwhile, the lives of their parents are coming to an end.
Distribution: Western, Northern, and Inner Tien Shan, the Issyk-Kul basin, the Pre-Fergana regions of Kyrgyzstan, Alay Valley.
Red Book