Showing posts with label stabilimentum. Show all posts
Showing posts with label stabilimentum. Show all posts

Wednesday, 15 September 2021

Wasp Spiders and their Egg-Sacs


Female Wasp Spider, home patch

We first encountered these fascinating spiders (Argiope bruennichi) in September 2020. Between 5th and 9th September last year I recorded four females, the large striped ones, in our home patch. 

We have enjoyed watching them again this year, though we have never seen more than three at a given time. This morning we discovered a second egg-sac in the long grass, so we hope this means that there will be more Wasp Spiders in 2022. 

These spiders like natural grassland, and we suspect it is our lack of mowing, the result of a pledge we made at the Suffolk Wildlife Trust Summit, that has attracted them to our wild garden. The long grass has certainly attracted grasshoppers, a key food source.

The discovery of a new egg-sac seemed a good moment to post some of our Wasp Spider photos. I hope you enjoy them!



Female with prey

Ditto

Female with egg-sac

Female near the stabilimentum
 

You can read about the 'ultra-violet reflective' stabilimentum or zigzag section of web here in the beginning of an article.


Underside of female (with egg-sac)

Female with egg-sac

Damp weather; female with parcel of prey

Stabilimentum

Evidence of two different spider species in close proximity 


Female upside-down, with egg-sac

Female and egg-sac

Female

Underside of female. Stabilimentum 

Stabilimentum


Do you see the tiny spider on the right? Is this a different species?

The male Wasp Spider is much smaller than the female. It is light brown and has two yellow lines running along the underneath of the abdomen.


Is the same spider as the tiny curled creature in the photo above?


... and this? Do leave a comment if you know.

Wasp Spider egg-sac spotted on Sutton Heath near Woodbridge

My thanks to David (Gill) for a couple of the photographs in this post.

Thursday, 17 September 2020

Wasp Spider with Egg Sac

It was exciting to find two Wasp spider egg sacs in the garden this afternoon. We have been watching three of these arachnids for days, but were not expecting this surprise. What a magnificent sac!


The second sac (above) was less conspicuous, and definitely more of a challenge for the camera.

I have learned a new word, stabilimentum, for the zigzag web you see in the photo below.

I noticed a tiny spherical object, which without magnification or glasses, looked like a seed head. However, I increased the size of the photo, and as you can see below it is a tiny spider. I wondered if could be the male Wasp spider, but since the female often eats her mate after mating, it may not be!

You can see the tiny spider a bit more easily in the next photo...


Wasp spiders are fascinating. The Argiope in their name, Argiope bruennichi, means 'silver-faced'; but I think their common name is a more obvious nomenclature!