Old Big-Eyes is Back

 Quiz time! Which species of spider is this the natural habitat of? 

One of them is Textrix denticulata, not particularly common in Leicestershire:

In January I was asked by the Charnwood Forest Landscape Partnership scheme if I could help refind the "Charnwood Spider", Mastigusa macrophthalma. This species was last recorded in Leicestershire 20 years ago, and on Charnwood 21 years ago. Rashly, I said yes, but bearing in mind some good arachnologists have been surveying on Charnwood in recent years, privately I had my doubts. For various reasons, I haven't been able to do much fieldwork yet this year, but recently I was able to revisit one of the last known Charwood sites for the species.

Success :-)

The other interesting thing about this record is that the spider was associating with Formica lemani (thanks to Gavin Gamble and Matt Hamer for the ID) under the rock, which I have not seen listed as a known associate for this species elsewhere:

I'm delighted to have been able to see and photograph this magnificant spider (now back under its home rock after a few photographs). However, I do worry a lot about the amount of disturbance and pressure on the site. My next move, having got my eye in, is to try and find new sites for the species, clinging to its ancient Charnwood home by its teeny tiny claws. 

 

Microscope Upgrade

My former stereo microscope (a GXM XTL3T101) has been my workhorse ever since I bought it. This is a mid-priced instrument and excellent value for money. One thing I have been finding however is that a high magnifications (40-45X) the quality of images dropped off compared with lower magnification. I have recently been able to trade-in my former microscope and upgrade to a GXM UltraZoom-3 stereo microscope: 

So what do I think of it? Well to be honest my initial hope was to do a bigger upgrade than this, but without paying Leica/Nikon/Olympus/Zeiss silly money. That proved to be difficult as I couldn't find anything suitable in the mid-priced - Russian oligarch price gap. The GXM UltraZoom-4 is a great instrument and closer to what I was hoping for, but sadly the working distance is too short, so I settled for the UltraZoom-3. 

After having a few days to use it, the GXM UltraZoom-3 is clearly an optical upgrade from the GXM XTL3T101, but perhaps not as mind-blowing as I was hoping for. Where it does score a big win is in the upper end of the magnification range (63x vs 45X on the XTL3T101). No only is the resolution better, but it is much brighter at the top end. This is particularly true of the trinocular light path to the camera, and I'm now able to use lower ISO settings and shorter exposures than before. The increased magnification also comes in handy - here's an illustration. A recent sample turned up the usual Tomocerid springtails. However, for the first time I was able to visualize the spines on the dens and identify the specimens as Tomocerus vulgaris without having to resort to using my compound microscope: 

That is an advantage over the GXM XTL3T101 and makes me feel I made the right decision with the upgrade.

 

Photography Equipment

I keep getting asked this question, so for the record, my photos are currently taken using:

• Macro photos taken using a Sony a6500, Sony FE 90mm F2.8 Macro G OSS +/- Raynox DCR-250, Godox V860IIIS flash, Cygnustech diffuser.
• Microscope photos taken using a Sony a7Rii on a GXM UltraZoom-3 trinocular stereo zoom microscope. (Prior to 2022, I used a GXM XTL3T101 microscope.)
•  Higher magnifications using a Sony a6000 on an Apex Practitioner compound microscope.
• Images stacked where necessary with Helicon Focus.
• Field Photographs (2023 on) taken using an Olympus TG-6 with the Olympus TG Light Guide.