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CRAB SPIDERS AND THEIR PREY

CRAB SPIDERS AND THEIR PREY. These spiders do not spin or have a web - although they do use the tough silken strands to secure their footing. These spiders kill by ambush.  They wait for an unsuspecting bee to land close, and then they strike. The spider extends their long legs and wraps them around the bee whilst sinking their fangs into their prey, injecting it with venom, typically with a neck grip, where they also feed.


But how does something so small take on such a large flying insect like a bee?

Crab spiders are very efficient killers, with a specialised pair of jaws with leglike joints. Each jaw is made up of a sharp retracted fang housed in a casing known as the basal segment.  The fang is hollow, with a duct at the bottom that connects to the spider’s venom gland.  When the spider grabs the bee with its fangs, it squeezes out the venom in a plunger-action, like a hypodermic syringe. 



The venom of these spiders is a neurotoxin that immediately paralyzes their prey.  Its nice to know that this neurotoxin is harmless to humans, but extremely poisonous to bees. 



So the paralyzing agents of the venom immobilises its prey, and in addition, crab spiders are disproportionately strong.  Like in this picture, the spider is carrying the whole weight of its large prey; and I think this is similar to a leopard, who can carry their heavy prey, up into a tree.


Here one has his prey underneath the flower, so he can digest it in peace.


They do not make webs and do not wrap their prey in silk, but they can produce a dragline -- a single thread that allows them to drop quickly to the ground to avoid predators (and photographers).  They can also use this to simply drop into the air, where the victim cannot get any purchase for its struggles.


You can see the draglines in this picture below


A hanging snack, which the small spider will pull up to the leaf later on, with its incredible strength.


another I found, just holding on with its back legs.

REMEMBER


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