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Banded

Here the banded crab spider takes his much larger prey

FROM MY BOOK....the BUGS OF HONG KONG CRAB SPIDERS (Family: Thomisidae) According to scientists, the Thomisidae’s common name of "crab" spider is of little biological significance. Some people would say that there is a definite resemblance to crabs; the way they hold their legs apart, and the way they scuttle sideways. Purists would say this is fanciful. Purists would say that this is subjective and anecdotal. Purists are clearly no fun. BANDED CRAB SPIDER (Ebrechtella pseudovatia) These spiders kill by ambush. They use tough silken strands to secure their footing, as they wait for an unsuspecting—much larger—bee or other flying insect to land close by, and then they strike. The spider extends their long legs and wraps them around the bee whilst sinking their fangs into their prey, typically with a neck grip. 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 leg-like 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 neurotoxin immediately paralyses their prey. In addition, crab spiders are disproportionately strong. I like to think this is similar to leopards, who can carry their heavy prey up into a tree. Whilst they do not make webs, and do not wrap their prey in silk, 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, still holding their large prey, where the victim cannot get any purchase or grip for its struggles. 40 spp. SEE THEM These little arachnids can be found on the stems, or on the flowers, of plants (especially bidens/daisies), waiting for their prey; positioning their bodies to look like the pollen-bearing centres of blossoms, and I find many on the daisies along my walk in Po Lo Che, Sai Kung.

    ©2018 by WildCreaturesHongKong.

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