Friday, July 27, 2012

A Flesh Eating Predator (Less than 3 mm long)



In my previous blog post I showed images of Lantana montevidensis.  When I brought the first sprig of Lantana back to the lab a small spider came along for the ride. Because so many different kinds of insects live on and in the Lantana, it makes sense that it would be a good a niche for a tiny predator.

This spider is less than 3mm from the most anterior part of its cephalothorax to the posterior end of its abdomen.

This is not a very detailed study because this is the first spider I have tried to image with the scanning electron microscope.  I had a problem with the build up of charge on the spider (which distorts the image). I will have to do some research and experimentation to figure out how to keep this from happening. 

Never the less, the following images should give you a feel for the marvelous strangeness of spiders - some of my most favorite creatures on the planet. 

Spiders this size can be frustrating to study - I have tended to avoid them. 
Now, thanks to my access to an SEM that will change. [22x]

A closer look at the abdomen [50x]
You may notice the absence of spinnerets on the posterior end.  On this species they are on the ventral surface of the abdomen.

 At 177x ridges on the abdomen become visible.


Dorsal Abdomen [384x]

 A look at the pedicel that connects the cephalothorax (right) to the abdomen (left) [255x]


 Cephalothorax and eyes [90x]

 Cephalothorax and eyes [160x]
Ridges become apparent


Talk about a head shot!  [471x]
I wonder where they got the ideas for Spider Man's costume?

 Femur of the hind most leg on the right side of spider [350x]

Patella at top, Tibia below [200x]
Look carefully and you can see three distinct type of hairs. 

Close up of hair types on tibia [903x]
Affect of charging is obvious - I am going to work on this.

Many years ago I had the opportunity to develop and teach an arachnology course to high school students.  I will be honest, studying spiders is difficult, but we made some progress and my students and I really enjoyed it.  When I changed schools, unfortunately, there was no interest in the class, so I haven't done a lot of spider work for some time.  Chancing upon this little spider has definitely rekindled my interest.

If you would like a chance to see and use a scanning electron microscope to image spiders or anything else, please don't hesitate to contact me.  Eastfield college is dedicated to supporting work in the STEM fields at all levels - for both faculty and students.  If you are not located near Eastfield College, we can still collaborate online.  I Skype.  Hope to hear from you soon.

Murry Gans
Scanning Electron Microscope Lab Coordinator
Eastfield College
972-860-7267


It All Begins Here!



2 comments:

  1. Your work is incredible. I love the process of zooming further in and in. It lets you know where you are and yet discover further and further.

    What is so amazing is how undamaged these tiny creatures are. You can see small areas where they have met the world, but still, it is amazing how clean they are.

    I was wondering: how small do you have to get to image bacteria and that kind of thing? The second image shows things that look like little bacilli, but I think you have to scan in at like 10x that level to see them. It would be cool to zoom in to see the mixture of life :)

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    Replies
    1. Many thanks for you comment. I really appreciate it.

      Bacteria are generally between 1 and 10 microns in size so they can be imaged with out too much magnification. In the microbiology lab we see them at 1000x with a light microscope. If you will notice the last image on this posting is at 903x and the distance between marks on the scale is 5 microns, so bacteria would show up here.

      Let me refer you to another of my blogs:

      http://gansspiders.blogspot.com/2013/06/trinity-river-audubon-center-june-14.html

      This shows a little weevil that seems to have bacilli around its eyes. I hope to culture them in September and identify them.

      Once again, thanks for your comment.

      Murry

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