10 November 2008

Garden orbweb spider, Eriophora pustulosa

Eriophora pustulosa

This little guy (those round things in front of his head confirm he's male) was hanging in the middle of his web this morning, long after sunrise. Somewhat surprising, but given the relative calm, I took the opportunity to photograph him without resorting to flash.

All content © 2008 Pete McGregor

5 comments:

  1. What fascinating detail - hairs on the body, shades of colour, and are those minute spines on the legs? All the symmetry. And why does the male have those round things and not the female?

    The air must have been very still if this was a flashless and therefore slightly longer exposure. I've never found a spider's web yet that wasn't moving slightly, even when it was calm, but perhaps the weight of the spider helped.

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  2. Lesley, some of those hairs on the legs have sensory functions; for example, trichobothria detect vibrations and/or air movements. When you look closely at spiders you really can't help being astonished at their intricacy. The round things aren't actually round — it's the angle of view that makes them seemingly spherical. They're modified palps which the male uses to inseminate the female; in effect, they're pumps which he fills with sperm so he can transfer it to the female. I think I'll stop there.

    On the full-size photo, it's possible to distinguish the spiracles on the abdomen; unfortunately, at the resolution of this photo they're undetectable. (The abdomen was about one and a half times the size of a match head.)

    There was a slight air movement which made photographing tricky. However, by being patient and waiting for the lulls, when the web would settle and remain still momentarily, I managed a high proportion of in-focus shots. I also stopped down to about f8–f11 to get enough just enough depth of field without bringing the background too much into focus. That probably compensated for any very slight movement.

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  3. Wow! This picture is awesome. Are your photos for sale? If so, how can I purchase this spider picture?

    Cheers
    Paterika

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