Huntsman spider

Heteropoda venatoria

The giant crab spiders ( Sparassidae, formerly Heteropodidae, Eusparassidae ) are a family of world-wide about 1018 species in 83 genera. They got the name through similarities to the Crab spiders with which they are not very closely related. In Central Europe, only one genus is native, the Husch spiders ( Micrommata ) Latreille, 1804 (including the Green Huntsman Spider ). In greenhouses also happens to the introduced species Heteropoda venatoria Latreille, 1804, the disclosure of focus is in the tropics and subtropics.

Appearance

Most giant crab spiders can be identified among other things by the position of the legs: the legs are slightly rotated in the hips ( coxae ). Characterized the legs show more or less clearly to the front, similarly to the shrimps. Many, but not all giant crab spiders have an inconspicuous brown or gray color. The legs are hairy and conspicuous spines, the body is smooth but not shiny. Some species are covered by substantial body size ( males occurring in Laos Heteropoda maxima hunter 2001 reach a leg span of 25 to 30 cm ). The banded giant crab spider ( Holconia ) is gray-brown to and wears stripes on the legs. The genus Neosparassus is brown and hairy.

Some larger types resemble tarantulas; However, a relationship does not exist.

Dissemination

Giant crab spiders are found in Australia, New Zealand, Southeast Asia, the Middle East in areas on the Mediterranean, in the U.S. in Florida and Hawaii, and most likely in many other tropical and subtropical areas. Today, they also occur in many parts of the world where they may not be home, such as China, Japan, Florida, Puerto Rico and in the southwestern part of the U.S. and Hawaii. Their occurrence is in principle possible everywhere, wherever they go as " stowaways " and can survive the winter.

The Senckenberg Nature Research Society, National Science Museum Tokyo, Museum of the Institute of Zoology, Chinese Academy of Sciences and the International Rice Research Institute Manila have a research focus here. They examine the radiations in Asia ( Pseudopoda, Sinopoda ), Southeast Asia and Australia ( Heteropoda, Pandercetes ) and Africa. In South Africa Western kinship relations and adaptations to different biomes are examined macro- ecological.

Way of life

One finds the giant crab spiders often in sheds, garages and other unfrequented places. They live in crevices of tree bark, but also occur in homes and cars. You can run very fast on walls and ceilings, as they can hold even on smooth surfaces.

The eyesight of these spiders is not nearly as good as that of jumping spiders ( Salticidae ). But enough to see bigger animals from a few decimeters away. Giant Crab spiders do not build networks, but seek out their food - mainly insects and other invertebrates - the wandering.

The females vigorously defend their egg sacs and also the offspring. Then take a threatening posture. If this is ignored, they can attack and bite.

Giant crab spiders are among the few families in which limited social behaviors were observed, something that is generally uncommon for spiders. So led scientists from Cornell University, a study on living in Australia Art Delena cancerides by, in the context of which could be in addition to said, resolute readiness to defend the females compared to their breeding even confirmed that overwhelmed from individual animals and prey animals in certain cases not in place be destroyed place, but dragged back into the mostly inhabited by several individuals slip angle spider where the catch is then shared with peers. The observations according to the researchers, this behavior seems to occur when the nocturnal D. is cancerides surprised by Sunrise during the hunt, thereby being forced to return with prey in their hideout.

Noises during mating ritual

Males of Heteropoda venatoria, one of the world's species have been abducted, recently observed here is that they produce a sound when you give them reason to believe that a female of the same species is near. Their method for generating sounds different from the stridulation with palps or other limbs of other spiders. The males anchor themselves firmly to the surface on which they sit and put your entire body into vibration. Hereby they announce themselves conspecific females, not to be mistaken for prey.