Wednesday, September 28, 2011


This is the hard to find Hyptiotes or Triangle Spider. It is a member of the only kind of spiders that do not have poison glands. Uloboridae. This is actually true, a non-poisons spider! A common held myth (even among experts!) is that all spiders produce toxic poison. The Uloborids do secrete some digestive enzymes into there pray but lack the traditional venom glands.

This spider can be very hard to find. I frist discovered it in Oregon in one place back in 1994. Hopeing to find it again, I returned to the same small forested area near a park and incredibly found one doing very well. What amazes me, is that I have been unable to find this species or any of it's relitives anywhere else here. There is a state park less then a mile from this small forested area which is in danger of being developed. If it is--this species which lives in a 'island' of forest may be gone forever in this area. This is very unlikely, but not impossible. I have not
conclusively identified it completely or proved that it is isolated to this area but these kind of things can and do sadly happen.

I took extensive photos before I released the spider hoping I will be able to use them to identify it and find out if possibly it exists on this small island of forest for a reason. To protect the species I am not going to tell where it is right now. For all I know it may have survived and may actually be stuck on this island of green surrounded by buildings and development. The area was logged once, but the wooded area has not been logged since at least the early 20th century--I am sure this forest area is likely well over 100 years old.

Spiders, just like all other species are put in danger by development. Sometimes a species will survive one logging cycle and live on in the area when plants and trees grow back. But not one after the other over and over. I have spent a very long time looking for this species somewhere else to confirm it is not just on this small island of forest. I have yet to find it anywhere else. It seems unlikely but not impossible. Spiders often have sporadic populations where some species live in certain places but no longer can exist where humans are due to there habitat needs or other issues. If I fail to find this spider in the near by protected park--I will definitely take steps to alert people to the fact that this spider may be holding out there and once that land is cleared--so will be the spider. I admit this is highly unlikely, but not impossible.

The tiny and hard to see Triangle spider has to be spotted among the many very common webs of the Linyphiinae species. The Linyphiinae make upside down webs and are probably the most common spider found through out the forested areas of Portland and the Northwest. (Below)

The "Money Spider"--the British name for it. Here often called the Dome spider. This is the most common species of visible spider. Since silk is everywhere from these spiders which often make webs on top of each other. It can be very hard to spot the Triangle spider in all these webs. We nearly gave up and found it only towards the end of the day. (Below--Dome Spider)

Close up of a Linyphiinae species. Very common in Forest Park and most all forested areas here in the Northwest. I may be jumping the gun here--but I have done surveys of many areas around where the Triangle spider lives and over the years never found it anywhere except this one small forested area. I hope to get an email proving me wrong and that this is a common species. Virtually gone is the large yellow Argiope aurantia in this area-- I used to find them everywhere as a kid and plan to try to locate populations again out in Beaverton where they possibly held out. Most of their habitat has been decimated and worse off poisoned by weed and insect killers. However the species is not extinct and thrives in other places in the US such as Northern California. But here in the Portland area you are very lucky to see one. I hope that is not the case with the Triangle spider. The Argiopes are large spiders and require large insect pray, this may be one reason why they are so hard to find. They also in some areas live in patches where you may find lots in one place and none in another.

A North American spider Field guide puts this family of spiders in North America but I do not think that it is not the same species as shown in the guide and I know it is not due to sexual dimorphism (large changes in colors or looks between male and female animals often leading to people thinking they found a new species). Was it brought in and got introduced to this area of forest? Is it a last hold out? I don't know, but 16 years later I found out it was still there and thriving. I hope that they don't cut down this last spit of land anyway--it could make a nice park and it is more then big enough. They made another area a park near-by--but I hope this land remains the way it is. It has a rich and diverse spider population even better then the nearby official park. Human activity is going to cause problems. I don't like it when they start paving the trails and changing the environment of a park. The point is a natural area--NOT a place to drive golf carts!

I wanted to catch every angle and way this spider acted. This is the typical pose when she sits on a twig or branch holding onto her web or to disguise when there is no web.

This little spider can RUN! I had to move my large camera with big flash gear on it very quickly to try to get a good shot of this spider. I do not leave them in the refrigerator like some people do because I think it is cruel and can also be very dangerous to the spider. If you forget it will die. So I do my best to catch shots on the move and wait for the spider to stop to catch a breath.

Usually I either don't capture a spider at all--or catch and release on scene so that the spider is not displaced from it's habitat. In this case however, I had to leave since it was getting dark so I chose to take this spider back to take detailed shots of it. I wanted to get eye shots and other details that may be very important to exact identification.

(Blend in perfectly)
This is how I found this spider--the Triangle spider is appropriately named. She makes a 'Pizza slice' shaped triangle of an orb web that often looks like another spiders dammaged web until you look close at the detail. I was able to get good shots before I captured her, this is exactly how she sat with her web on her legs. She holds it tight and waits for an insect to fly in. They blend in incredibly to the foliage around them looking like a stem or a bit of bark or even a berry as shown here. Another reason why this spider is so hard to find. The spider is just to the right of the middle of this picture--camouflage that is truly incredible.

--Web drawing coming soon--

I realized that being deep in a forest it was very hard to get good shots of her web. You have to bounce a wireless flash off the web at the right angle. You get the idea about how it makes a perfect section of an orb web only. Just a slice of a pizza. How this came about I have no idea. She then holds it from the tip with the other sides secured to foliage.

Back when I started doing survays of spiders in High school I would note the technique of each species and in each area--as they can vary--that spider uses to escape when afraid. This technique can tell you something about the most common predators in the area of that species. One common technique shared by many web building spiders is to turn into a ball and drop down very quickly onto the ground. DO NOT PICK UP a spider in this position! You may hurt the spider and also the spider is afraid and thus likely to bite you. This spider is totally harmless but in some species it is a bad idea. The best protection against spider bites is to ware gardening gloves. This 'drop technique' makes it very hard for a predator like a bird or bat to find the spider once it's in deep grass or leaves. Here is the spider after it dropped in its' escape position.

(Spider Moss farm)
I found this hanging while taking shots of other spiders on our trip. I thought it was interesting.

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