Jumping spider
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{{Taxobox
| color = pink
| name = Jumping spiders
| image = JumpingSpider.JPG
| image_width = 235px
| image_caption = Paraphidippus aurantius
| regnum = Animalia
| phylum = Arthropoda
| classis = Arachnida
| ordo = Araneae
| familia = Salticidae
| familia_authority = Blackwall, 1841
| subdivision_ranks = Genera
| subdivision =
Bagheera
Corythalia
Eris
Freya
Ghelna
Habronattus
Hentzia
Lyssomanes
Maevia
Marpissa
Messua
Metacyrba
Naphrys
Paramarpissa
Paraphidippus
Phidippus
Portia
Salticus
Sarinda
Sassacus
Sitticus
Synemosyna
Thiodina
Trite
Zygoballus
}}
The jumping spiders (family Salticidae) contains more than 500 genera and over 5,000 species, making it the largest family of spiders. Jumping spiders have good vision and use it for hunting and transportation. They are capable of jumping from place to place, secured by a silk tether.
Contents |
Habitat
Jumping spiders live in a variety of habitats. Tropical forests harbor the most species, but they are also found in temperate forests, scrub lands, deserts, the intertidal zone (in Malaysia), even mountains (one species is reported to have been the spider collected at the highest elevation, on the slopes of Mt. Everest. If this is its natural habitat, then it is probably living as a scavenger, feeding on the insects that are transported up there by the wind and then frozen to death.)
Appearance
Jumping spiders are generally recognized by their eye pattern. They typically have eight eyes arranged in three or four rows. The front, and most distinctive row is enlarged and forward facing to enable stereoscopic vision. The others are situated back on the cephalothorax.
Colors and patterns vary widely. Several species of jumping spiders appear to mimic ants, beetles, or pseudoscorpions. Others may appear to be parts of grass stems, bumps on twigs, bark, part of a rock or even part of a sand surface.
Like other spiders who are fast and active hunters, they have a well developed trachea system.
Behaviour
Jumping spiders are generally diurnal, active hunters. Spiders do not have muscles like mammals or reptiles do, instead they rely on an internal hydraulic system, they extend and retract their limbs by altering the pressure of fluid (blood) within them. When a jumping spider is moving from place to place, and especially just before it jumps from one place to another, it tethers a filament of silk to whatever it is standing on. Should it fall for one reason or another, it climbs back up the silk tether.
Unlike almost all other spiders, they can quite easily climb on glass. They also use their silk to weave small tent-like dwellings, where females can protect their eggs and to serve as a shelter while moulting.
Vision
Jumping spiders have very good vision centered in their anterior median eyes (AME). Their eyes are able to create a focused image on the retina, which has four layers of receptor cells in it. Physiological experiments have shown that they may have up to four different kinds of receptor cell, with different absorption spectra, giving them the possibility of up to tetrachromatic color vision, with sensitivity extending into the ultra-violet range. Color discrimination has been demonstrated in behavioral experiments.
Diet
Hunting
Jumping spiders capture their prey by jumping on it from several inches away, and they may jump from twig to twig or leaf to leaf. They can jump thirty times their body length. They can carry out complex maneuvers such as detours around obstacles in order to reach their prey. Their eyesight is much better than that of other spiders and most, if not all, insects. Most other spiders will only eat prey that they have captured live because they are unable to see dead prey (some long-legged sac spiders and anyphaenid sac spiders are exceptions as they recognize insect eggs as food) but jumping spiders will eat flies that have been killed for them. One jumping spider is even known to only capture mosquitos full of blood, using their eyesight and smell.
Nectar
Even if there are no spiders that are pure vegetarians, there are some jumping spiders which include nectar in their diet. So far none are known to feed on pollen or seeds. When insects land on plants such as the partridge pea, which offers the spiders nectar through their extrafloral nectaries, the jumping spiders helps protect the plant in return by killing and eating the insects.
Gliding
At least one species of jumping spiders, known as the Gliding Spider (Saitis Volans) from Australia, has an abdomen with two wing-like flaps that can be tucked underneath it when not in use. When the spider is leaping, it can use its flaps to extend the jump and glide short distances through the air.
Venom
Some jumping spiders may bite to protect themselves if disturbed. However, these small creatures much prefer to escape and hide, and will only bite if provoked and no means of escape is at hand. While the bite of a larger jumping spider can be painful, only a few species seem to produce any other effects. Almost all spiders (except hackled orb-weavers) have venom, but the venom of most spiders is not worse than the venom of a bee.
Reproduction
Jumping spiders also utilize their vision in complex visual courtship displays. Males are often quite different in appearance than females and may have plumose hairs, colored or metallic hairs, front leg fringes, structures on other legs and other, often bizarre, modifications. These are used in visual courtship in which the colored or metallic parts of the body are displayed and complex sideling, vibrational or zigzag movements are performed in a courtship "dance." In recent years it has been discovered that many jumping spiders may have auditory signals as well, with amplified sounds produced by the males sounding like buzzes or drum rolls.
Image:Jumping Spider, Frontal View.jpg Image:Antspider.JPG
References
- Crompton, J. (1954). The Life of the Spider. Mentor.
- Elias, D. O., Mason, A. C., Maddison, W. P., & Hoy, R. R. (2003). Seismic signals in a courting male jumping spider (Araneae: Salticidae). Journal of Experimental Biology, 206, 4029-4039.
- Forster, L. M. 1982. Vision and prey-catching strategies in jumping spiders. American Scientist 70165-175.
- Jackson, R. R. 1982. The behavior of communicating in jumping spiders (Salticidae). In P. Witt and J. Rovner (eds).Spider Communication Mechanisms and Ecological Significance, p. 213-247. Princeton, New Jersey.
- Kaston, B. J. (1953). How to Know the Spiders, Dubuque, Iowa.
- Nakamura, T., & Yamashita, S. (2000). Learning and discrimination of colored papers in jumping spiders (Araneae, Salticidae). Journal of Comparative Physiology A, 186, 897-201.
- Richman, D. B., G. B. Edwards and B. Cutler. (2005). Salticidae. pp.205-216 in D. Ubick, P. Paquin, P. E. Cushing, and V. Roth (eds.) Spiders of North America: an identification manual. American Arachnological Society.
- Richman, D. B., and R. R. Jackson. (1992). A review of the ethology of jumping spiders (Araneae, Salticidae). Bulletin of the British Arachnological Society, 933-37.
- Jackman, John A. (1997). A Field Guide to Spiders & Scorpions of Texas. Gulf Publishing Company. Houston, Texas. p.127.
External links
- Jumping Spiders of North America
- World Spider Catalog
- Jumping Spiders of the World
- Jumping Spiders of NW-Europe
- Jumping spiders of Australia
- American Jumping spiders
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