Argiope keyserlingi
Encyclopedia
Argiope keyserlingi is a common species of orb-web spider
found on the east coast of Australia
, from central New South Wales
to southern Queensland
. It is very similar in appearance to the closely related north Queensland species, Argiope aetherea
. A. keyserlingi is commonly found in large populations in suburban parks and gardens, particularly amongst the leaves of Lomadra longifolia. Like many species of orb-web spider
, A. keyserlingi shows considerable sexual size dimorphism
, with the females being many times larger than the males. Mature females can be seen during the summer months and it is not uncommon to see multiple males on the web of one female.
This spider is commonly known as the St Andrew's Cross spider, due to the construction of bands of silk forming the arms of an X-shaped cross, similar to the one upon which St. Andrew is traditionally said to have been crucified. Termed web decorations
or stabilimenta, these bands are thought to increase prey capture in this species, however, in other species they have been found to protect the spider against predators.
A. keyserlingi is an important model species in studies of spider ecology
and behaviour. Using this species scientists have investigated sperm competition
, sexual size dimorphism
, cryptic female choice, the role of pheromones in mating behaviour and the function and evolution of web decorations
.
Its main predators in Sydney
are mantids and bird
s.
. The spider is also commonly called the Crucifix spider.
Spider
Spiders are air-breathing arthropods that have eight legs, and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...
found on the east coast of Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, from central New South Wales
New South Wales
New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...
to southern Queensland
Queensland
Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...
. It is very similar in appearance to the closely related north Queensland species, Argiope aetherea
Argiope aetherea
Argiope aetherea is a common, large orb-web spider This species is commonly known as the St Andrew's Cross spider due to the characteristic cross-shaped web decorations often included in their webs by female spiders. A. aetherea is similar in appearance to A. keyserlingi, however female A....
. A. keyserlingi is commonly found in large populations in suburban parks and gardens, particularly amongst the leaves of Lomadra longifolia. Like many species of orb-web spider
Spider
Spiders are air-breathing arthropods that have eight legs, and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...
, A. keyserlingi shows considerable sexual size dimorphism
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
, with the females being many times larger than the males. Mature females can be seen during the summer months and it is not uncommon to see multiple males on the web of one female.
This spider is commonly known as the St Andrew's Cross spider, due to the construction of bands of silk forming the arms of an X-shaped cross, similar to the one upon which St. Andrew is traditionally said to have been crucified. Termed web decorations
Web decorations
A web decoration or stabilimentum is a conspicuous silk structure included in the webs of some species of orb-web spider...
or stabilimenta, these bands are thought to increase prey capture in this species, however, in other species they have been found to protect the spider against predators.
A. keyserlingi is an important model species in studies of spider ecology
Ecology
Ecology is the scientific study of the relations that living organisms have with respect to each other and their natural environment. Variables of interest to ecologists include the composition, distribution, amount , number, and changing states of organisms within and among ecosystems...
and behaviour. Using this species scientists have investigated sperm competition
Sperm competition
Sperm competition is a term used to refer to the competitive process between spermatozoa of two different males to fertilize an egg of a lone female. Competition occurs whenever females engage in promiscuous mating to increase their chances in producing more viable offspring...
, sexual size dimorphism
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
, cryptic female choice, the role of pheromones in mating behaviour and the function and evolution of web decorations
Web decorations
A web decoration or stabilimentum is a conspicuous silk structure included in the webs of some species of orb-web spider...
.
Its main predators in Sydney
Sydney
Sydney is the most populous city in Australia and the state capital of New South Wales. Sydney is located on Australia's south-east coast of the Tasman Sea. As of June 2010, the greater metropolitan area had an approximate population of 4.6 million people...
are mantids and bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s.
Name
The species is named in honour of arachnologist Eugen von KeyserlingEugen von Keyserling
Eugen von Keyserling was a German arachnologist.He was the author of Die Spinnen Amerikas, and completed Die Arachniden Australiens on behalf of Ludwig Carl Christian Koch.-External links:...
. The spider is also commonly called the Crucifix spider.