Argiope (spider)

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Argiope
Reflective silver argiope in a stabilimentum-free web in California.jpg
Reflective silver argiope in a stabilimentum-free web in California
Scientific classification e
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Order: Araneae
Infraorder: Araneomorphae
Family: Araneidae
Genus: Argiope
Audouin, 1826[1]
Type species
Aranea lobata
Pallas, 1772[1]
Species

See text.

The genus Argiope includes rather large spiders that often have a strikingly coloured abdomen. These spiders are distributed throughout the world. Most countries in tropical or temperate climates host one or more species that are similar in appearance. The etymology of Argiope is from a Latin word argentum meaning silver.[2] The carapace of Argiope species is typically covered in silvery hairs.

Common names[edit]

Argiope sp. blending in to elaborate stabilimentum in Tanzania
An argiope's web with stabilimentum in Independence, Missouri

Argiope bruennichi is commonly known as the wasp spider. In Australia, Argiope keyserlingi and Argiope aetherea are known as St Andrew's cross spiders, for their habit of resting in the web with legs outstretched in the shape of an X, the cross of St Andrew.[2] The large white zigzag in the centre of its web is called the stabilimentum or web decoration.[2]

In North America, Argiope aurantia is commonly known as the black and yellow garden spider, zipper spider, corn spider, or writing spider, because of the similarity of the web stabilimenta to writing.

The East Asian species Argiope amoena is known in Japan as kogane-gumo. In the Philippines, they are known as gagambang ekis ("X spider"), and gagambang pari ("priest spider", due to the spider's body resembling a priest's head with a mitre).

Web[edit]

The average orb web is practically invisible, and it is easy to blunder into one and end up covered with a sticky web. The very easily visible pattern of banded silk made by Argiope is pure white, and some species make an "X" form, or a zigzag type of web (often with a hollow centre). The spider then aligns one pair of its legs with each of the four lines in the hollow "X", making a complete "X" of white lines with a very eye-catching spider forming its centre.

The zigzag patterns, called stabilimenta, reflect UV light.[2] They have been shown to play a role in attracting prey to the web, and possibly in preventing its destruction by large animals. The centres of their large webs are often just under 1 metre above the ground, so they are too low for anything much larger than a rabbit to walk under. The overtness of the spider and its web thus has been speculated to prevent larger creatures from accidentally destroying the web and possibly crushing the spider underfoot.

Other studies suggest that the stabilimenta may actually lead predators to the spider; species such as A. keyserlingi place their web predominantly in closed, complex habitats such as among sedges.

As Argiope sit in the centre of their web during the day, they have developed several responses to predators, such as dropping off the web, retreating to the periphery of the web, or even rapidly pumping the web in bursts of up to 30 seconds, similar to the motion done by the unrelated Pholcus phalangioides.[3]

Reproduction[edit]

The male spider is much smaller than the female,[4] and unassumingly marked. When it is time to mate, the male spins a companion web alongside the female's. After mating, the female lays her eggs, placing her egg sac into the web. The sac contains between 400 and 1400 eggs.

These eggs hatch in autumn, but the spiderlings overwinter in the sac and emerge during the spring. The egg sac is composed of multiple layers of silk and protects its contents from damage; however, many species of insects have been observed to parasitise the egg sacs.

Bite[edit]

Like almost all other spiders, Argiope are harmless to humans. As is the case with most garden spiders, they eat insects, and they are capable of consuming prey up to twice their size. A. savigny was even reported to occasionally feed on the small bat Rhynchonycteris naso.[5]

They can potentially bite if grabbed, but other than for defense, they do not attack large animals. Their venom is not regarded as a serious medical problem for humans; it often contains a wide variety of polyamine toxins with potential as therapeutic medicinal agents.[6] Notable among these is the argiotoxin ArgTX-636 (A. lobata).

A bite by the black and yellow garden spider (Argiope aurantia) is comparable to a bee sting, with redness and swelling. For a healthy adult, a bite is not considered an issue.

Though they are not aggressive spiders, the very young, elderly, those with compromised immune systems, or those with known venom allergies should exercise caution, just as one would around a beehive.[7]

Taxonomy[edit]

The first description of the genus Argiope is attributed to Jean Victoire Audouin in 1826,[1] although he wrote that the genus was established by Savigny.[8] In the first edition of the work in which the description appeared (Description de l'Égypte: Histoire Naturelle), Audouin used the spelling "Argyope", for both the French vernacular name and the Latin generic name.[8] In the second edition, he continued to use "Argyope" for the French vernacular name, but the first mention of the Latin generic name had the spelling "Argiope", although the binomial names of the species continued to use "Argyope".[9] This led to controversy as to whether Audouin had intended to correct the spelling of the generic name, which is derived from the Greek αργιόπη. In 1975, the International Commission on Zoological Nomenclature validated the spelling "Argiope", on the basis that the change from the first to the second edition was an intended correction.[10][11]

Species[edit]

As of May 2016, the World Spider Catalog accepted the following species:[1]

Footnotes[edit]

  1. ^ a b c d "Gen. Argiope Audouin, 1826". World Spider Catalog. Natural History Museum Bern. Retrieved 2016-05-07. 
  2. ^ a b c d Whyte, Robert; Anderson, Greg (2017). A Field Guide to Spiders of Australia. Clayton South Vic. 3169: CSIRO publishing. p. 80. ISBN 9780643107076. 
  3. ^ Blamires, Hochuli & Thompson (2007).
  4. ^ Levi H. W. (1983). "The Orb-Weaver Genera Argiope, Gea, and Neogea from the Western Pacific Region (Araneae: Araneidae, Argiopinae)" (PDF). MUSEUM OF COMPARATIVE ZOOLOGY. Harvard University p.253. Retrieved 2018-08-04. 
  5. ^ Timm & Losilla (2007).
  6. ^ Strømgaard, K. & Mellor, I. (2004). "AMPA receptor ligands: Synthetic and pharmacological studies of polyamines and polyamine toxins". Medicinal Research Reviews. 24 (5): 589. doi:10.1002/med.20004. 
  7. ^ Hawkinson, Candice. "Beneficials in the Garden: Black-and-Yellow Argiope Spider". www.tamu.edu. Texas A&M University. Retrieved 2014-09-24. 
  8. ^ a b Audouin (1826), p. 121.
  9. ^ Audouin (1827), p. 328.
  10. ^ Melville, R.V. (1975). "Opinion 1038 Argiope Audouin (Arachnida, Aranea): placed on the official list of generic names in zoology". Bulletin of Zoological Nomenclature. 32 (2): 105–109. Retrieved 2017-08-21. 
  11. ^ Levi, Herbert W. (2004). "Comments and new records for the American genera Gea and Argiope with the description of a new species (Araneae: Araneidae)". Bulletin of the Museum of Comparative Zoology. 158 (2): 47–65. doi:10.3099/0027-4100(2004)158[47:CANRFT]2.0.CO;2. 

References[edit]

External links[edit]