I’m tinkering with getting better images of these silly spiders, and my latest attempt is to build a little itty-bitty photographic studio on a benchtop. I can mount light sources and reflectors on the bench, play with backgrounds, and position specimens where I want — they are extremely obliging models, as long as I’m bringing in the whole cardboard frame their webs are structured around, which is a slight limitation, because the space has to be big enough for not just the spiders, but also their whole cage. I’m also putting the camera on a tripod and locking it down — it’s heavy — and just manipulating the airy light spiders to get them in position.

They’re all good girls. As long as I’m not messing with the web, they are quite calm and well-behaved, so I can just leave these venomous spiders out of their cages as long as I want and they don’t try to escape or get aggressive at all, they rest suspended happily while I move gadgets around them. I was also able to get some respectable video out of the set up, too, so you might have that to look forward to, too.

I think I could go for this look.

Javier Rupérez

I just need a recipe for more eyes, and I might be able to pull it off.

(Now imagining going into the local hair salon with this photo, and telling them this is the style I want.)

Arachnologists spend a lot of time staring at spider genitals, since they’re often key to classifying them. I’ve mentioned that I want to work out some taxonomic ignorance of my own, so I’m finding myself trying to do likewise. This morning I was working with my shiny new toy to see if I could resolve the important details with an SLR tricked out with a 100mm macro lens and 65mm of extension tubes. This represents the maximum magnification I can squeeze out of this set up, short of mounting the animals under the microscope, which would give me hella more magnification.

I’d rather not go that route, though, because it requires more manipulation of the animals and I’d rather keep them happy and relaxed. Right now in their cages, they lounge about upside down, all quiet and mellow, their legs spread out and flaunting their genitalia to the sky. I can just pop the lid and zoom in with my camera lens and they’re totally unperturbed and au naturale, exposed and waiting for their close-up. This would also be the case if I encountered them in the wild, where I’m typically not lugging a microscope around with me. The hope is that my camera would have enough oomph to get all the diagnostic details.

Long story short…probably not. I’ll throw in a few photos below the fold, but they aren’t quite good enough to see what I need to see.

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Right now, I’m cash poor (please keep that in mind if you think you can get rich by suing me) — I’m having no trouble paying the mortgage or putting food on the table, so I’m immensely privileged that way, but coming off a half-pay year and with annoying legal expenses, I haven’t been able to buy toys for myself for a while…until now. My rule is that all the gift cards I get from the Amazon Affiliate program are mine to splurge on whatever, and I’ve been saving them up for a few months, so that I can get this: a Tokina at-X 100mm f/2.8 PRO D Macro Lens.

I’ve been doing all my macro photography with a Canon Nifty-Fifty a set of cheap macro extension tubes, which work great on a budget. That was the kit lens on my camera, and the extension tubes were only about $20, so it was an easy intro to macro photography. The setup takes good photos, too. The only catch, I thought, was when you put 65mm of extension tubes on your lens, your working distance plummets to nearly nothing. You’ve got to push that lens right up next to your subject, which isn’t always optimal, so I got myself a big beautiful 100mm macro lens with a true 1:1 image ratio so that I’d have a little more flexibility.

It arrived today, so I allowed a little time to try it out, after finishing all my exam grading.

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Here’s another wintertime project I’ve got to work on. I’ve got all these spiders I collected, and I’m confident that they’re all of genus Parasteatoda. However, we’ve got two species in this genus here in Minnesota: P. tepidariorum, which is the darling model system in developmental biology, and P. tabulata, which is more obscure, but I suspect is fairly common around here. In the literature, P. tabulata is the one that builds nests of debris suspended in their webs; P. tepidariorum isn’t described as doing that, but who knows? I’ve collected a lot of spiders in outdoor environments with the fancy cribs made of leaves and gravel, and the ones I collect indoors don’t do that. Is this just an environmentally-induced variant?

That’s not what the taxonomic literature says. Rather, there is some contentious debate about distinguishing the two, which is made clear by close-up inspections of dissected genitalia. Their epigynes have subtly different shapes.

This is not a playing field I’m competent to contest. You should see this stuff: intricate, carefully drawn illustrations of the P. tepidariorum epigyne vs. equally detailed drawings of the P. tabulata epigyne. OK, gang, I surrender — I struggle to figure out what the heck I’m looking at there. I clearly need to work on my knowledge of spider sexual organs, not something I ever expected I’d have to do. I’m also handicapped by the fact that I’m working with live animals, and killing them and ripping out their genitals and clearing them in clove oil is kind of antithetical to breeding them. Also, I like my little spider friends.

So I’m trying to get photos of their genitals to see if I can distinguish them. Here’s one. Pretty racy, I know.

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I’m done with seeking out spiders in their natural environment, for a while. I’m keeping an eye on a few outdoors (Jenny By-The-Front-Door still lives, despite the recent snow, and there’s a nearby compost bin I have my eye on), but mainly I’m settling in for a winter of laboratory observations now. So here’s a quick review of how I’m raising my spider family.

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