Spinneret (spider)

Spinnerets are the Ausführorgane the spiders for their synthesized in the silk glands spider silk. The extremely moving mostly multi-unit trailer in the fourth and fifth abdominal segment were present in the original four pairs, but with the recent species they are disposed of three or two pairs. Sitting at the tips, the bobbins, the actual excretory organs for the silk on floating platforms.

The spinnerets are like the limbs moved mainly by flexor muscles while stretching through the hemolymph happens. The muscles are attached to the hinge and skins through the entire spinneret to move the bobbin. Thus, the spinnerets can be unfolded, perform for the starting points of a thread, rotational movements, and moved up and down. The abdomen is also movable, which increases the radius of action of the spinnerets.

The bobbins can be compared with needles, the opening measures only fractions of a millimeter in diameter. They can be divided into several types, which perform various functions, such as Leimabsonderung, scaffolding threads, signal threads, catching threads, cocoons, etc., which are associated with the different silk glands. Several different types of spinning reels sitting on a spinneret. Cribellate spiders have three pairs of spinnerets, the fourth pair is converted to cribellum. The cribellum some cribellater catch Wollweber can carry up to 20,000 bobbins, the openings of which is only 10 nm ( 1/100.000 mm ) in diameter. In Leimfadenweber there are three pairs of spinnerets, and the fourth pair converted to Colulus. Leimfadenweber can have up to six silk glands.

Spinnerets are converted extremities of the 4th and 5th segment of the opisthosoma. Four pairs of spinnerets are present only in the limbs spiders.

Source

• Foelix, Rainer F. 1979. Biology of spiders. Georg Thieme Verlag Stuttgart. ISBN 313575801x

• Anatomy (eddy lots)
• Arachnologie