A Saintly Spider
|[Note Guidelines] Photographer's Note|
|The St. Andrews Cross spider (Argiope keyserlingi) is a fairly common inhabitant of forests, woodlands, heaths and urban parklands through much of temperate and tropical Australia. The female (pictured) is substantially bigger than the male (see workshop), with a body size of around 15mm compared to the males’ 3-4mm. The leg span is about 60mm. The female spider builds a large orb-shaped web of around 500mm and sits in the middle with its eight legs spread in an X configuration. The spider will often add a broad white zigzag web (called stabilimentum) to match its leg position. Although it was originally thought to provide stability to the web, it is now understood that this additional web is used as a predator deterrent (wasps and birds) and is apparently extra-sticky. When threatened, the spider shakes the web and the white X blurs, confusing the predator and giving the spider a few moments to attempt escape. |
The common name comes from the white X having a resemblance to shape of the cross on which St. Andrew was reputedly crucified in AD60. St. Andrew is the patron saint of Scotland and the Scottish flag is a white X on a blue background.
The bite of this species is moderately painful to humans, but not lethal.
This shot is the underside of a female, and was captured at Wangi Falls in Litchfield National Park. It is cropped from the original, sharpened and NeatImage was used to remove noise from the background.
In the workshop I have included another image, which shows the male in the top corner. This gives an impression of the comparative size.
As with many spiders, the poor male has to choose the right moment to mate with the female. If he chooses a moment when the female is not receptive, she will treat him as prey and eat him. Mating occurs in late summer and autumn and the female lays her eggs in a greenish coloured egg sac, which is suspended near the web in foliage. Despite this, the egg sacs are often the target of parasitic wasps and flies.
Fisher, Luc, willie, Callie, red45, LordPotty, Signal-Womb, mogens-j has marked this note useful
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- [2004-12-21 19:12]
Chris, thanks for sharing your note. I found it interesting. Well done on your capture.
This is a great photograph with good composition and focus. Love it.
- [2004-12-22 1:23]
Very good shot Chris. Good detail and nice composition. Well done
Very nice macro, focus a bit soft on the spider's face.
- [2004-12-22 4:18]
Stunning and fearsome lady - I would not like to meet her by accident! Nice note too, thanks.
- [2004-12-22 4:39]
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Straight form X-Files this is X-Spider :-) Great composition and note. Colorful and beautiful.
- [2004-12-22 7:11]
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Very good macro Chris.
Is it X-mas picture ?.
Good sharpness, colours and composition.
Very well done.
Quite a distinctive pattern on this spider...and this is just the underside. is the upper as colourful? Some interesting information too. Thanks.
Very nice macro on this female love her markings. Strange looking patterns on both sides of web. Super note.
Very nice capture of an interesting critter Chris. Very good educational note.
- [2004-12-23 15:42]
Very good shot wit excellent sharpness and exposure.
Very well done and thanks for posting.
- [2005-03-29 2:14]
nice photo. I love the details.
- carle (104)
- [2005-06-01 15:51]
Nice spider pic Chris - and a scary looking one too!
Good colors and detail, nice DOF. I'd hate to wake up next to one of these suckers.