Spiders No.19 – The Strange Eyes of the Male Pholcus

[Walter Piorkowski]

Leitz Ortholux microscope
4X Leitz projection eyepiece plus 1/3x relay lens

Image No.1, Face on view. Prominence clearly displayed.
85 images at 5 micron increments
Nikon 10x Achromat objective
Leitz dry darkfield condenser D 0.80

Image No.2. View 45 degrees above front view.
99 images at 5 micron increments
Nikon 10x Achromat objective
Leitz dry darkfield condenser D 0.80

Image No.3, Top view.
137 images at 5 micron increments
Nikon 10x Achromat objective
Leitz dry darkfield condenser D 0.80

Image No.4, Top view showing more of the carapace.
41 images at .001 inch increments
Leitz UO 6.5 X Achromat ULTROPAK objective
Leitz dry darkfield condenser D 0.80

Canon 50D
Zerene and Photoshop processing.


This spider is not the only one with six eyes arranged in two triads, but their placement on a prominence is unusual. The lenses are very transparent and views from several different angles were needed to see if they existed at all.

It is very interesting to note that no retinas seem to be visible in any eye. When you look through the lens, what appears underneath is the same material that makes up the rest of the carapace. These spiders rarely venture out into the sunlight, being found in dark places like cellars. I wonder if the apparent lack of a retina is due to were they live?

Take note of the two small anterior median eyes. They have a concentric ring like element in the lens, best seen in the top view and somewhat in the face on left eye.

Walt

[Mitch640]

I wonder if the apparent lack of a retina is due to were they live?

You mean Beloit?

Actually, I have been wondering about those Beloit spiders for awhile now. I do not recall ever seeing a white spider anywhere, when I think on it. But what ever they are, your photography work of them is exceptional. But like the spiders, makes me ask more questions than they answer.

[john sp.]

Hi Walt, I've very much been enjoying your spider series. This series made realize that you must have a convenient way for holding these small insects and being able to manipulate them to present different points of view to the microscope. I was curious about how you solved this issue. If you've already addressed this, give me a tip as to where and I'll hunt it up. Thanks.

John

[Walter Piorkowski]

Thanks again Mitch, and hay, Beloit and its Beloit spiders aren't that bad.

Hi John. The answer to your question is complicated. You use the word convenient in the handling of these spiders. In this series the process has been anything but. It is labor and time intensive.

I break the handling up into two processes depending on whether the subject is alive or dead. For the live subjects a custom made container is made for each specimen depending on its size and the working distance of the objective that I am likely to use. I use clear plastic tubing of various diameters capped off with glass cover slips.

To be honest, the live work is always a work in progress. A lot of views and features are just not possible. I am working on solutions for future images as time permits.

For the dead subjects, things can get quite gruesome. Surgical manipulations, strap down boards and squishing between weighted shapes are my methods. I make a mini version of a medieval torture rack out of fiberglass experimenters electronic perf boards which have many holes every few millimeters so the subject can be strapped down using fine wire. Additional heavier wire can be used on one end to “prop” the rack up at any angle desired. Again, working with the holes.

My squish method is based around a selection of tiny glass prisms, cubes and flat pieces of glass that I have hand cut and ground. With the various angles, I can press them up against the subject and hold it fast at thye angle I want. The beauty of this method is that the light is not blocked from the subject.

I don’t want to give away all my secrets but you get the idea. Basically, work at it with a lot of imagination and materials you can get ahold of.

Walt

[Mitch640]

Beloit and its Beloit spiders aren't that bad.

I think they are beautiful, unique. And your making them world famous.

[john sp.]

Walt, I think it says something that your end results make it look easy to someone who is unaware of all the work that actually went into the process. I knew enough to recognize that being able to shift the subject to get just the right point of view of the eyes required some dexterous manipulation, but what I imagined this involved fell well short of the mark.

John