|of weber farmhands|
the weber farmhands (Opiliones) belong to the Kieferklauenträgernand is an order of the Arachnids (Arachnida). World-wide about 4000 kinds are well-known, which reach body lengths of 2 to 22 millimeters. The weber farmhands contain kinds, which are penetrated and milbenförmig, besides in addition, the well-known langbeinigen kinds. The largest representativesthe weber farmhands are Trogulus torosus stygnoides with only 6 mm of body length, with a body length of 22 mm as well as Mitobates, but are enough for legs with 160 mm.
In Central Europe some kinds of the weber farmhands are endangered and are located on the red list.This is to be attributed among other things to the fact that they are relatively well examined because of their way of life particularly easily with soil traps imprisoned to become to be able and their ecological requirements therefore contrary to the genuine Web spiders. The moreover one must assume that weber farmhandsare very localfaithfully and therefore particularly sensitive. They have a large Potenzial for the bio indication, which is only small used however from absence at interest in the Arachnids.
Table of contents
4,1 Cyphopalpatores 4,2
Laniatores 5 Web on the left of [ work on ] building of the weber farmhands in contrast to the Web spiders from the Hinterkörper (Opisthosoma), in addition they order neitherover poison still over Spinndrüsen. Weber farmhands are not called therefore of Arachnologen genuine spiders.
As all Arachnids (Arachnida) possess it eight legs, which are extremely long with many kinds. With Mirobates stygnoides for example the legs that can do25fache of the actual body length constitute. Besides there are however also many kinds without this remarkable extension of the legs, or with even - for spider conditions - proper stub legs, which are hardly longer with some kinds than the body. In case of oneAttack can separate the weber farmhand from a leg (Autotomie), which then, still twitching, whom aggressor is to confuse. With young animals this leg is usually regenerated within two to three striking doing gene.
The Pedipalpen of manyKinds often look like legs, so that by the unbedarften observer also 5 pairs of legs are counted. They can be trained as impactable catch organs (with the Laniatores), serve however usually groping, the reproduction or (with food intake) as member masses, those thatKieferklauen (Cheliceren) the food push over.
The Kieferklauen is three-membered and at some groups very large and remarkably; in the strong and long first basic member they are carried forward horizontally like thorns. Giftdrüsen are missing however, weber farmhands feed their bootyliving. A characteristic of all weber farmhands remarkable under the magnifying glass is a pronounced hill, which carries the eyes. This eye hill can be trained as a relatively long handle also, so that many weber farmhands under the binocular seen almost as Stielaugen toodesignate are. The visual sense is relatively badly developed, even if ultraviolet light is noticed. Which role plays this with these night-active animals, is unclear.
The body of some kinds is occupied with partly bizarren and colourful thorns and points/teeth, itselfonly under the microscope to recognize leave. These body extensions have which function, which remind of crocodiles or Warane, is still unsettled.
Also with weber farmhands there can be a Geschlechtsdimorphismus. Males of the Laniatores are remarkably more darkly than the females, there their Chitinhülleis thicker. In addition they possess usually a clearly stronger Skulpturierung.
way of life of the weber farmhands
usually in the Bodenschicht living weber farmhand build no Fangnetze, but nourish themselves mainly of microscopically small Gliederfüssern. In the loose strew the hardwood forest,in gardens, meadows, hedges or naturenear parks they graze off with their Cheliceren plant parts died, on which microscopically small, decomposing animals sit. Nevertheless they settle also the Bodenschicht or ground level also in extreme biotopes and ecological systems, like dunes, Moorlands, heaths. The Pedipalpen gropes thereby ahead which serves just like the long legs as tracers. Except for few exceptions weber farmhands are night active, who settle the soil in damp hardwood forests or moorlands with hundreds of individuals per square meter.
Who would like to observe it, should itself in a warm and dry late summer eight into the forest gone, over there 1 to 3 hours after sunset best lying or kneeling with a flashlight the soil anzuleuchten. The well camouflaged animals are after a certain habituation time to frequently only discover, then one notices however soon hundreds on smallest area. The activity is however very weather dependent.
Their way of life is probably a reason for their endangerment. The intensification of forestry and the agriculture, and the rapid loss of biotopes such as hedges, break and break forests might not be favorable the weber farmhands.
with the weber farmhandstakes place the transmission of the sperm cellses directly. Males and females with the front bodies face each other and the male lead its Penis by the Cheliceren through into the genital area of the female. The genital aperture of both sexes becomes by the training one Scelerite shifts, in the case of the Phalangioida to direct under the mouth area. In the developing genital chamber lies a eregierbares and mobile pipe, which is used from the females to the oviposition (Ovipositor) and from the males to the Begattung as Penis.
Puts the eggs the female into small holes or columns at the soil, with some South American representatives of the Gonyleptidae a breeding care was observed, with that the male a nest builds and it, as well as the eggs and the young animals of many females, alsothose it paired, guarded itself.
systematics of the weber farmhands
the exact systematic position of the weber farmhands within the Arachnids are not so far clarified. Kury shows the current conditions (2003) (http://acd.ufrj.br/mndi/Aracnologia/checklaniator.htm [check list OF valid genera OF Opiliones OFthe World])
classical way is used it as group of sisters of the mite-well-behaved ( Kapuzenspinnen and mites), whereby this relies alone on the reason that at these groups the second pair of run legs is somewhat longer than the remaining. The formerly good argumentthe scourgeless sperm cellses it becomes void by the fact that the original Kapuzenspinnen possesses clearly begeisselte sperm cellses.
An alternative conception (Shultz 1990) arranges the weber farmhands as group of sisters of a Taxons consisting of scorpios , pseudo scorpios and roller spiders. Here the main reason is based on thatBeginning places of the leg musculature and the structure of the mouth before area.
The weber farmhands classical-proves internally divided into the three subordinations Cyphophthalmi , Palpatores and Laniatores. After phylogenetischen investigations however the group of the Palpatores does not form a natural group, but enclosure only for main line representative thatCyphophthalmi, therefore are combined both original Taxa into the Cyphopalpatores.
this group covers all kinds of the weber farmhands spread in Central Europe. These are divided into the following families (kind selection incompletely):
- Siro duricorius
- Cladonychiidae (= Erebomastidae)
- Holoscotolemon unicolor
- Fadenkanker - Nemastomatidae
- Nemastoma lugubre
- Nemastoma bimaculatum
- Mitosoma chrysomelas
- Paranematosoma quadripunctatum
- Histricostoma dentipalpe
- Brettkanker - Trogulidae
- Anelasmocephalus cambridgei
- Trogulus tricarinatus
- Schneckenkanker - Ischyropsalididae
- Ischyropsalis hellwigi
- cutter - Phalangiidae
- Amilenus aurantiacus
- Dicranopalpus gasteinensis
- Lacinius of dentiger
- Lacinius ephippiatus
- Lacinius horridus
- Lophopilio palpinalis
- Mitopus morio
- Odiellus spinosus
- Oligolophus hanseni
- Oligolophus tridens
- Opilio canestrinii
- Opilio parietinus
- Opilio saxitilis
- Paroligolophus agrestis
- Phalangium opilio
- Platybunus bucephalus
- Rilaena triangularis
- astrobonus of laevipes
- Gyas titanicus
- Leiobunum blackwalli
- Leiobunum limbatum
- Leiobunum rotundum
- Leiobunum rupestre
- Nelima sylvatica
the Laniatores exclusively occur in the tropical rain forests of South America. They are characterised by robbery-leg-like Pedipalpen and tracer-similar second run legs. The males of these animals are strongly armored and have very large Hüftglieder (Coxen), whereby those of thelast pair of legs with thorns are reinforced. In addition some kinds are equipped with remarkable sculpture and thorns.
Web on the left of
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see also: Systematics of the Gliederfüsser