Ethan Bright 0 Report post Posted August 25, 2006 I came across a vial of some small Dolometes fishing spiders I collected about 8 years ago. I took some very quick photos through my microscope this afternoon. I hope they come out alright. (The first isn't great because I didn't properly compress the image). Enjoy! Habitus Close-up of eyes Mouthparts Spinnerets Quote Share this post Link to post Share on other sites
uffepuffe 0 Report post Posted August 25, 2006 Great photos Ethan! The Dolomedes Fimbriatus is the biggest spider we have here in sweden and an impressive hunter it is! It can run out on the water surface and catch insects on the surface or even dive down under water to catch tadpoles and small fish, but I am sure you knew that already I did this realistic fly that were supposed to imiate it about a year ago. Ulf Quote Share this post Link to post Share on other sites
fly time 0 Report post Posted August 25, 2006 Those are some cool picts guys, they give me chills just lookin at them!! Quote Share this post Link to post Share on other sites
harleyhunter 0 Report post Posted August 25, 2006 Hey Ulf, I've always loved that creepy spider of yours. Great tie again buddy! -Sam Quote Share this post Link to post Share on other sites
Ethan Bright 0 Report post Posted August 28, 2006 Ulf, That is great work! How much time did it take to do it? And did it catch any fish? Like most spiders, most people over-estimate the size of spiders because of the out-streatched appendages. Still, I've seen some really big fishing spiders (ca. 3-4 cm body length), and they are very scary especially when you're expecting to see them. That and the beautiful yellow-and-black garden (orb) spider are our largest spiders (in Michigan). If I remember from the movie Microcosmos, there's a spider (diving spider) species in Europe and Asia that constructs an air bubble in which to hide, drag its prey, and even lay its eggs. Do you have these in Sweden? Cheers, Ethan Quote Share this post Link to post Share on other sites
uffepuffe 0 Report post Posted August 28, 2006 Thanks alot Ethan. This one was tied as a display fly only, but would probably fish well since the underbody is made of foam so it would float like a cork! It takes me about an hour to do one of these guys. Yes we do have these diving spiders here in sweden. If I am not misstacen it's the Argyroneta aquatica that you are refering to. Here in sweden they are called "water spiders" plain and simple. The will grow to just under 2 cm and just as you say, creates an air bubble under water in which the live, feed and breed. Ulf Quote Share this post Link to post Share on other sites
Ethan Bright 0 Report post Posted August 28, 2006 Yes, that's the spider. They're also interesting in that, in contrast to most terrestrial spiders, the male is larger than the female. Delores Schuetz and Michael Taborsky did some interesting research on this topic: Schütz D, Taborsky M. 2003. Adaptations to an aquatic life may be responsible for the reversed sexual size dimorphism in the water spider, Argyroneta aquatica. Evolutionary Ecology Research, 2003, 5: 105–117. Below is the abstract: Argyroneta aquatica is the only spider that spends its whole life under water, and one of very few in which males are bigger than females. We hypothesized that the unusual ecology of the water spider is responsible for its exceptional sexual size dimorphism. If ecological parameters influence optimal body size for locomotion, the size of the more mobile sex (males) is expected to vary more between populations that vary in these ecological conditions than that of the other sex (females). Indeed, sexual size dimorphism differed significantly between four populations of A. aquatica studied at Vienna, and this variation depended more on variance in male size than in female size. We found that, apart from size, body shape and the relative length of the first pair of legs also differed significantly between the sexes. In land spiders, among which females are usually larger than males, small male size has been attributed to the better mobility of smaller individuals, as generally males are the more mobile sex in spiders. In aquatic animals, larger individuals have mobility advantages over smaller ones. We therefore hypothesized that, in A. aquatica, large rather than small size may facilitate locomotion, and hence that males are better divers than females. This was confirmed by the results of diving experiments. It is probable that male diving superiority is mainly due to their longer first pair of legs. Female size determines fecundity to a large extent. We wished to determine which size constraints could prevent females from growing bigger. Female size may be limited by the costs of building air bells, which they use as a retreat and for brood care. In laboratory experiments, we found that females build larger air bells than males and that air bell size correlates with body size in females but not in males. Females need to collect air from the surface to refill their bells more often than males. We conclude that the need for males to move efficiently under water and the costs to females of building a retreat and breeding shelter may be important determinants of body size and morphology. Hence the reversed sexual size dimorphism in A. aquatica may be greatly influenced by mechanisms of natural selection. Quote Share this post Link to post Share on other sites
uffepuffe 0 Report post Posted August 29, 2006 Fascinating facts Ethan! I just did a google search for the Argyroneta aquatica and it's really cool to see the air "bell" it does for itself. As I understand it the spider actually gathers the air, buble for buble, from the surface bringing it down to the bell and slowly filling it with air until it is totaly filled. Amazing! Quote Share this post Link to post Share on other sites
bugcam 0 Report post Posted September 12, 2006 A few lears ago, I saw one blue and one green six-spotted fishing spider at a bog near my home. They were georgous! Didn't have a camera that day but I will go back and see if there are any more there! We also have goldenrod spiders and big spiders with a cats face on their back in my garden. I love, love, love spiders! That is a spectacular spider that you tied, uffepuffe. Quote Share this post Link to post Share on other sites
billb 0 Report post Posted September 13, 2006 uffepuffe: Great spider fly! Ethan: Impressive photos -- those fangs (I'm sure they're not proerly called that) are pretty impressive. --Bill Quote Share this post Link to post Share on other sites