Tuesday, July 10, 2007

More from Rugosa World

A July bioblitz of the Rosa rugosa alba in the yard would take hours and hours, and could be done every day and produce new results each day. And this rose bush, about 2 metres high and almost as wide, is mere steps from the front door.

I've been watching a number of Misumena vatia over the past few weeks (inspired by Spider WebWatch). These spiders, ambush predators, stay in one spot for extended periods, making them excellent subjects for long observation. I can see what they're eating, how fast they're growing, and even guess as to when they're pregnant, and then eventually see their egg cases. There's one on the Rugosa now I've been watching for some time that has a prodigious appetite. She moves occasionally as blooms come and go and I can usually find her again by looking for the sucked-dry rose chaffers she's dropped onto the leaves below her chosen spot. This morning she has a moth, and twice now she's had a small bumblebee, which surprised me: small, but not compared to her.

Misumena vatia at Lunch

So there I am, staring at the rose bush, looking for spiders, and now that I'm developing an eye for them I'm seeing that there are many other spiders (and many other critters all together) living there. I was startled by the one below because of its white abdomen. Most of the M. vatia I find on the bush are white, so that's what I look for in a scan, but this little one was no crab spider.

What long, spindly legs you have

The spider is sitting just below a developing rose hip (not an apple), and in the upper left of the picture you can see the leg of the rose chaffer it was wrapping up when I first spotted it, which gives an idea of how small this spider is.

I couldn't see a web, just a few random strands of webbing, and the obvious silk production and webbish behaviour of wrapping prey. I hunted around for an ID, gave up and sent an image to BugGuide. In very short order I had a response (click on the link to see just how short). Take a look at Enoplognatha ovata, a member of the cobweb spider family. I did, and I think they got it!

I really think it is Enoplognatha ovata


burning silo said...

Great little spider. I don't think I've found one of them before. I'll have to be on the lookout for one!

Pamela Martin said...

Since I found that one I've been seeing them, or others similar, everywhere--cobwebbing in foliage, and on the underside of mullein leaves.