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Home -> Kingdom Animalia -> Phylum Arthropoda -> Class Arachnida -> Order Araneae -> Suborder Neocribellatae -> Family Salticidae -> Species Portia fimbriata

Portia fimbriata
jumping spider



2008/10/05 07:50:40.160 GMT-4

By Andrea Jackson

Kingdom: Animalia
Phylum: Arthropoda
Class: Arachnida
Order: Araneae
Suborder: Neocribellatae
Family: Salticidae
Genus: Portia
Species: Portia fimbriata

Geographic Range

Portia fimbriata are found in the rainforests of Australia, Sri-Lanka, and Malaysia. (Jackson 1992)

Biogeographic Regions:
oriental (native ); australian (native ).

Habitat

P. fimbriata require the moist conditions found in tropical rainforests. (Jackson and Hallas 1986)

Terrestrial Biomes:
rainforest .

Physical Description

The appearance of P. fimbriata is unlike that of other spiders. They are about 1 cm long, and have cryptic markings, tufts of hair and long spindly legs. Because of their unusual appearance, P. fimbriata are often mistaken for detritus by both prey and potential predators. (Jackson 1992)

Reproduction

P. fimbriata are able to mate either on or off of the web. Male and female both participate in a courtship dance. This dance consists of a series of jerky walking, leg shaking and tapping behaviors. The male mounts the female, the female spins around on the male, and they copulate. Mating can also take place while both male and female are suspended in mid-air from a silk guyline. Interestingly, in other species of the genus Portia, when the female spins around on the male while suspended in air, she eats the male after copulation. P. fimbriata does not display this cannibalistic behavior.

Fertilization is delayed. About an hour after copulation, P. fimbriata males deposit a drop of sperm on the web. The female moves over the sperm deposit, and facilitates fertilization. (Jackson 1992, Jackson and Hallas 1986)

Behavior

P. fimbriata are largely solitary.

P. fimbriata use their unusual appearance that is similar to detritus to evade other predators, and to help them approach prey.

(Jackson 1992)

Food Habits

P. fimbriata are primarily araneophagic, meaning they eat other spiders, including other salticids. P. fimbriata also eat insects and the eggs of other spiders.

P. fimbriata are predatory, and they use several methods of predation. One is aggressive vibratory mimicry, in which P. fimbriata climb on to the web of their victim and use their legs and palps to pluck signals on the web. They imitate the signals of their intended victim's prey. When the victim comes close to P. fimbriata, they make their attack.

P. fimbriata are specialists at catching cursorial salticids. Most cursorial salticids don't build typical webs, but they spin orb-like nests out of silk. P. fimbriata make vibratory signals on the silk of the nest. When the salticid pokes its head out to investigate, they attack. This is called nest probing.

Another type of predation used by P. fimbriata is cryptic stalking. In this method, the hunter moves very slowly. If the salticid turns to face it, P. fimbriata pulls its palps back and out of the prey's view and freezes. In this position P. fimbriata resembles a piece of detritus. Eventually it approaches the prey from behind, and swoops in for the kill.

Other jumping spiders of the genus Portia exhibit aggressive mimicry, nest probing, or cryptic stalking. P. fimbriata is the only species that exhibits all three behaviors. P. fimbriata also displays species specific predation tactics. The jumping spider Euryattus (species unknown), is sympatric with P. fimbriata in the rainforests of Queensland, Australia, but is not known to exist with any other P. fimbriata population. Euryattus females do not build a nest, but suspend a rolled-up leaf by silk guylines from a rock ledge or tree trunk. Male Euryattus go down guylines onto the leaves and court by flexing legs and making the leaf rock back and forth. The female comes out of the nest to either mate or drive the male away. P. fimbriata mocks the behavior of the male, and when the female comes out of the nest, P. fimbriata attacks. Populations of P. fimbriata that do not live with Euryattus in nature do not drop down from guylines to attack Euryattus in this way.

Unlike other salticids, P. fimbriata are web building spiders. P. fimbriata use their webs not only as nests, but as a mode of predation. They build their webs near, and fastened to, the webs of another species, creating a single compound structure. It then is easy for a P. fimbriata to invade the neighboring web. The web of P. fimbriata is not sticky, but sometimes does catch insects. In this situation, P. fimbriata usually do not eat the insect, but wait for spiders from the a neighboring web to approach, and eat them instead. (Jackson 1985, Jackson 1998, Jackson 1992, Daiqin and Jackson 1997)

Economic Importance for Humans: Negative

None indicated.

Economic Importance for Humans: Positive

None indicated.

Conservation Status

IUCN Red List: [link]:
Not Evaluated.

US Federal List: [link]:
No special status.

CITES: [link]:
No special status.

We have no text on this topic for this species. Look to the sidebar on the right for some limited information.

Other Comments

P. fimbriata, like other salticids, has vision that is superior to that of many other spiders. P. fimbriata has six small lateral eyes that detect movement in a field of view that is as large as 360°. The two principal eyes are located on the front of the head and provide acute vision. This is indicated by their predation of spider eggs. Because eggs to not move, it is necessary to have acute vision to find them. (Jackson 1985, Jackson 1998)

Contributors

Andrea Jackson (author), University of Michigan.
Phil Myers (editor), Museum of Zoology, University of Michigan.

References

Jackosn, R., R. Wilcox. 1998. Spider-eating spiders. American Scientist, 86: 350-357.

Jackson, R., S. Hallas. 1986. Comparative biology of jumping spiders. New Zealand Journal of Zoology, 13: 423-489.

Jackson, R. 1985. A web-building jumping spider. (Australian species *Portia fimbriata*). Scientific American, 253: 102-110.

Jackson, R. 1992. Eight-legged Tricksters: spiders that specialize in catching other spiders. BioScience, 42: 590-598.

Li, D., R. Jackson. 1997. Influence of diet on survivorship and growth in *Portia fimbriata*, an araneophagic jumping spider (Arnae: Salticidae).. Canadian Journal of Zoology, 75: 1652-1658.

2008/10/05 07:50:41.407 GMT-4

To cite this page: Jackson, A. 2000. "Portia fimbriata" (On-line), Animal Diversity Web. Accessed October 11, 2008 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Portia_fimbriata.html.

Disclaimer: The Animal Diversity Web is an educational resource written largely by and for college students. ADW doesn't cover all species in the world, nor does it include all the latest scientific information about organisms we describe. Though we edit our accounts for accuracy, we cannot guarantee all information in those accounts. While ADW staff and contributors provide references to books and websites that we believe are reputable, we cannot necessarily endorse the contents of references beyond our control.

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