Pedipalp

The paired Pedipalpus is a feature of spiders (Arachnida ). It is a converted extremity in the head region of the animals.

The Pedipalpus is converted primarily to a tactile organ; a pair of scissors he does not contribute in the basic pattern very likely. The Pedipalpus is homologous with the mandibles of crustaceans and Tracheentiere and obeys the arachnids on the chelicerae or jaws claw.

Scorpions

Within the Arachnida the Pedipalpus and the chelicerae has been modified in many ways, especially through the multiple convergent features with scissors. These were seen in the scorpions, whip scorpions, pseudo- scorpions and spiders hood. The pseudoscorpions they are also equipped with poison glands.

Scourge spiders

The scourge spiders the pedipalps form large fishing legs with breakable foot members. Adhesive organs on the pedipalps are found in the rolling spiders, these are used to catch prey as well as adhesion structures on smooth stones.

Spiders

Even within the spiders of Pedipalpus was restructured. Here he serves in males as sperm carriers.

Bulb

The male spider is the last link of the pedipalps, originally the foot member, transformed into a mostly three-part Palpenorgan. This is called Palpenorgan bulb and contains internally a cavity for the transport of the semen ( Spermatophor ). It is filled by the males of their own genital opening or at a sperm web. During mating, this organ can be inserted into the female genital opening. For the Chitinspangen must be tailored to the body ( the cymbium ) on the genital opening of the female. Accordingly, this is called a key - lock principle. Within many groups of spiders an accurate species identification is possible only on the basis of these structures.

In haplogynen spinning the globe is simply built and mostly uniform spherical or pear-shaped. In entelegynen spinning the bulb consists of several mutually movable sclerites and intervening membranous Hämatodochen. The first sclerite is the cymbium. The cymbium covered median, largest sclerite of the eyeball, which is called Tegulum and Spermatophor contains. Then the embolus following the actual sperm -transferring organ. It bears at its peak the mouth of the Spermatophors and can be rolled up very long and tubular.

Other Features

Other functions are the keys through the thick and long hair, the drums or plucking the network for intraspecific communication, such as in courtship, or on the substrate, presumably for orientation, eg in jumping spiders. Some species also have stridulating organs on or in the pedipalps.

Swell

• Rainer F. Foelix: Biology of spiders. Georg Thieme Verlag, Stuttgart 1979. ISBN 3- 13-575801 -X