maengmoom kradoht (แมงมุมกระโดด)

Thai. ‘Jumping spider’. Generic name for any spider in the family Salticidae, with more than 500 described genera and about 5,000 described species, the world's largest family of spiders, accounting for about 13% of all species, with most of them found in tropical forests. Its tiny members are in English, similar as in Thai, commonly referred to as jumping spiders, as they are capable of jumping, often several times the length of their body. Unlike grasshoppers that have strong muscular legs, jumping spiders are capable of leaping forward by altering their blood (bodily fluid) pressure within their limbs, using a well-developed internal hydraulic system. Before they jump over heights, they secure themselves with a thin silken thread, in case they should fall. Jumping spiders are known for their hairy legs, superior eyesight, curiosity and inquisitiveness. They have eight eyes and the largest ones, the principal eyes in the front of the head are very specialized and are very good at seeing spatial detail. Jumping spiders do not posses eyeballs, but have mushroom-shaped eyes, that consist of a fixed lens on the outside and a tiny retina at the back of a long tube on the inside, which the spider is able to move due to muscles that surround these so-called eye-tubes. This allows the spider to look from one side to the other while sitting still and make for a perfect hunting tool when ambushing prey without any outer movement. Mostly carnivorous, they are diurnal (fig.), active hunters and usually stalk their prey, though there are some species that also eat nectar and pollen, and at least one species that lives on plant matter. They are naturally territorial, ready to defend their living space and will challenge any intruder. Hence, they are in some Asian countries, such as Singapore, Malaysia and Hong Kong, caught and trained to take part in spider fighting competitions in special arachne arenas. These typically consist of a large, elevated, rounded and flat dry leaf, on which they compete until one is either thrown off or falls off, or flees the scene. See also WILDLIFE PICTURES. 回